The impact of the material distribution of porousified LTCC on the effective permittivity investigated by finite 3D field simulation - Steinhäußer, Frank; Talai, Armin; Kölpin, Alexander; Weigel, Robert; Bittner, Achim; Schmid, Ulrich (Mikrosystemtechnik-Kongress (MST), 2013)
Apart from other advantages, such as its robustness, the high permittivity of LTCC (Low Temperature Cofired Ceramics) multi layer technology is one of the most important reasons why it is nowadays well established in high frequency devices and systems. However, reduced emission is not desired in every application. Antennas require a substrate with a low permittivity in order to achieve maximum emitter efficiencies. The chemical composition of LTCC allows the local introduction of air by means of a selective etch process. Due to this selective and diffusion controlled process the generated porousification is not homogeneous depending on the penetration depth. On the basis of measured lateral material distributions, the effect on the effective permittivity can be shown by performing 3D field simulations. The distributions are graphically derived from material cuts, which were realized by focused ion beam technology. From the complex trends, conclusion regarding the alteration of the inner chemical phase distribution as well as the quality and the bearing capability of the surface can be obtained.
elib2cris::1512001600,steinhaeusser2013

The Influence by Trapezoidal Conductor Shapes on Ring-Resonator based Material Characterization up to 110 GHz - Talai, Armin; Steinhäußer, Frank; Bittner, Achim; Schmid, Ulrich; Weigel, Robert; Kölpin, Alexander (International Conference on Numerical Electromagnetic Modeling and Optimization for RF, Microwave, and Terahertz Applications, 2014)
Material characterization by ring-resonator based measurements is well established since the early 20th century. Since then, the demand on spectral complex permittivity characterizations of RF materials and dielectric covers at higher microwave frequencies rises. Nowadays, both free space applications, e.g. 77 GHz automotive radar systems, and dielectrics for microchip packages require accurate knowledge of the relative permittivity in order to optimize RF circuit designs. With increasing frequencies, the conductor shape of photochemically etched ring-resonators gets more influence on the effective ring radius, and therefore the measured resonance frequencies, which results in an error for the relative permittivity determination. This paper provides correction factors for the ring radii up to 110GHz, compensating the altered field distribution due to trapezoidal edges.
elib2cris::1512001600,talai2014a
Keywords: CAD Modeling; Effective Permittivity; Field Simulation; material characterization; Microstrip Structure; Ring-Resonator; Trapezoidal Conductor

The Influence of Interference Sources on a Magnetic Field-Based Current Sensor for Multiconductor Measurement - Itzke, Alexander; Weiss, Roland; DiLeo, Taylor; Weigel, Robert (IEEE Sensors Journal, 2018)

The Influence of Pilot Symobols for Viterbi Decoding and Soft Viterbi Output based on the Parameters of the IEEE 802.11a Standard - Witschnig, Harald; Aichberger, Roland; Hutzelmann, Holger; Huemer, Mario; Weigel, Robert; Springer, Andreas (IASTED International Conference on Wireless and Optical Communications, 2003)
elib2cris::1512001600,witschnig2003a

The Influence of Rain on Small Aperture LiDAR Sensors - Fersch, Thomas; Buhmann, Alexander; Kölpin, Alexander; Weigel, Robert (German Microwave Conference, 2016)
The influence of rain on pulsed LiDAR systems with a miniaturized aperture and small laser beam cross sections was investigated based on two situations deemed critical. First, discrete rain drops appearing very close to the laser aperture could lead to a complete deflection of the laser beam out of the original direction when drop and beam overlap. Our semi-probabilistic, semi-analytical model however indicates that the rate of deflected scan events is negligible. Second, the emitter surface could be, to a greater or lesser extent, covered with drops of various size, degrading the performance. We found an optimum ratio between drop diameter and laser beam diameter, favoring larger laser beams. Also this effect however is, in total, not critical.
elib2cris::1512001600,fersch2016
Keywords: LiDAR

The Integrated Filterbank Based Scalable MPEG-4 Audio Coder - Herre, Jürgen; Allamanche, E; Brandenburg, Karlheinz; Dietz, Martin; Teichmann, Bodo; Grill, Bernhard; Moriya, Takehiro; et al. (105th AES Convention, 1998)
Vorträge und Veröffentlichungen auf Konferenzen_Gehörangepasste Datenreduktion

The mDOM - A multi-PMT optical module for IceCube-Gen2 - Classen, Lew; Kappes, Alexander; Karg, Timo; Kretzschmann, Axel; Kölpin, Alexander; Lindner, Stefan; Röber, Jürgen (DPG-Verhandlungen, 2016)
Following the discovery of an astrophysical neutrino flux by IceCube in 2013, planning is under way for the next generation neutrino telescope at the South Pole, IceCube-Gen2, which will significantly enhance and expand IceCube’s sensitivity both towards high neutrino energies as well as in the low-energy regime. In the scope of these efforts, a novel multi-PMT optical sensor is being developed which, following the KM3NeT design, consists of an array of several small PMTs inside a transparent pressure vessel. This design provides some significant advantages compared to the conventional single-PMT module design, such as an increased effective area, homogeneous coverage of the full solid angle, and intrinsic angular sensitivity. The talk presents an overview of the project and its current status, featuring hardware development, testing, and simulation efforts.

The MTT-S Awards Committee-Evaluating the Excellence, Quality, and Service of Distinguished Microwave Engineers [AdCom Awards Committee] - Weigel, Robert (IEEE Microwave Magazine, 2022)
Reports on news of interest to MMTS society members.
CRIS-Team WoS Importer:2022-10-28

Theoretical Derivation of Bandwidth Limits of a Symmetric Acoustic-Wave-Lumped-Element Resonator (AWLR) Module - Wagner, Michael; Leuschner, Stephan; Weigel, Robert; Hagelauer, Amelie Marietta (ANALOG 2018; 16th GMM/ITG-Symposium, 2018)
This paper focuses on theoretical investigations on "Acoustic-Wave-Lumped-Element Resonator" (AWLR) modules that have gained much interest in the last few years regarding general progress in radio frequency (RF) filter techniques and design. It is shown how the bandwidth characteristics depend on the electro-mechanical coupling factor of the employed piezoelectric material. General approximation formulas for the achievable 3 dB-bandwidth and for the maximum achievable bandwidth of symmetric AWLR modules are given. The results of the mathematical derivation are verified by simulation.<br

Theoretical Limits and Interpolation based Improvements of a Correlation Based True-Speed-Over-Ground Estimation - Reißland, Torsten; Weigel, Robert; Kölpin, Alexander; Lurz, Fabian (2023 IEEE Topical Conference on Wireless Sensors and Sensor Networks, 2023)
For a radar based True-Speed-Over-Ground measurement system an interpolation based precision improvement is presented. The system is based on the cross-correlation of two radar receive signals. The theoretical basics of the interpolation are thoroughly introduced and its limits are determined for the general case and for a specific hardware. Measurement results including the interpolation are presented and compared to the former implementation.<br
CRIS-Team Scopus Importer:2023-03-17
Keywords: radar; correlation; interpolation; velocity measurement; rail transportation

Theoretical studies on leaky-SAW properties influenced by layers on anisotropic piezoelectric crystals - Wallner, Paul; Ruile, Werner; Weigel, Robert (IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2000)
Theoretical studies on the behavior of leaky-SAW (LSAW) properties in layered structures were performed. For these calculations rotYX LiTaO 3 and rotYX LiNbO3 LSAW crystal cuts were used, assuming different layer materials. For LSAWs both the velocity and the inherent loss due to bulk wave emission into the substrate are strongly influenced by distinct layer parameters. As a result, these layer properties like elastic constants or thickness have shown a strong influence on the crystal cut angle of minimum LSAW loss. Moreover, for soft and stiff layer materials, a different shift of the LSAW loss minimum can occur. Therefore, using double-layer structures, the shift of the LSAW loss minimum can be influenced by appropriate chosen layers and ratios
elib2cris::1512001600,wallner2000
Keywords: SAW; Crystal

Theory and Realization of High-end Analog-to-Digital Converters based on the Principle of Successive Approximation - Ohnhäuser, Frank (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2008)

The Passive Structure of a Sixport-Receiver for the K-Band - Kölpin, Alexander; Winter, Sebastian; Eireiner, Thomas; Weigel, Robert (Mediterranean Microwave Symposium (MMS), 2005)
elib2cris::1512001600,koelpin2005b

The Phase Noise and Clock Synchronous Carrier Frequency Offset based RF Fingerprinting for the Fake Base Station Detection - Ali, Arslan; Fischer, Georg (WAMICON 2019, 2019)
This paper presents very promising radio frequency (RF) fingerprinting techniques for the terminal-based detection of fake base station (FBS) in a wireless cellular network. The proposed schemes are based on identifying the analog hardware impairments of the transmitter. In this regard, phase noise analysis and its measured signatures reveal that low to medium end software defined radio (SDR) acting as FBS can certainly be detected if the detecting terminal’s own phase noise is at least 10- dB better than the transmitter. However, for medium to high end FBS, a computationally efficient network synchronized carrier frequency offset (CFO) approach has been proposed and the measurement results confirm that the regular base stations (RBS) that are clock synchronized show identical CFO values whereas, the FBS show large and random offset values. Furthermore, the CFO stability (Frequency offset vs. time) signatures illustrate that an FBS running by its own lazy clock show a large instability in the frequency offset values and even in case of a precision clock, fluctuations vanish though the stabilized offset is still large enough for a user terminal to distinguish the FBS from the RBS.<br
CRIS-Team Scopus Importer:2019-08-06
Keywords: phase noise; carrier frequency offset; RF Fingerprinting; fake base station; software defined radio; carrier frequency stability; hardware impairments; physical layer security

Thermal Memory Effect Characterization of GaN based Class ABJ Power Amplifier using Intrinsic Temperature Measurement - Jueschke, P.; Fischer, Georg (2018 IEEE TOPICAL CONFERENCE ON RF/MICROWAVE POWER AMPLIFIERS FOR RADIO AND WIRELESS APPLICATIONS (PAWR), 2018)
CRIS-Team WoS Importer:2019-02-22

Thermal Memory Effect Characterization of GaN based Class ABJ Power Amplifier using Intrinsic Temperature Measurement - Jüschke, Patrick; Fischer, Georg (IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications (PAWR), 2018)

Thermal Modeling and Measurement of a Power Amplifier Module for a Silicon-Ceramic Substrate - Frank, Astrid; Silva Cortes, Victor Arturo; Michael, Steffen; Hagelauer, Amelie Marietta; Fischer, Georg (German Microwave Conference, 2018)

The Roots, Rules, and Rise of RFID - Heidrich, Jürgen; Brenk, Daniel; Essel, Jochen; Schwarzer, Stefan; Seemann, Kay; Fischer, Georg; Weigel, Robert (IEEE Microwave Magazine, 2010)
This article has offered a brief excerpt of the basic requirements and current development trends in (passive) RFID systems in different application areas. Even after reaching a sophisticated state of development, RFID technology is still dependent on sufficient acceptance at the market. Conventional bar code systems lack programmability, have low storage capability, and need a line-of-sight connection to the reader. If the fall in prices for low-cost tags continues, barcodes could be largely replaced in some years. In this case, additional features like positioning or sensing will become even more attractive for commercial and industrial application fields.
elib2cris::1512001600,heidrich2010a
Keywords: Access control; Antenna accessories; Antennas and propagation; Design engineering; Knowledge engineering; Radiofrequency identification; Signal processing; Supply chain management; Tagging; Transponders

The Six-Port in Modern Society - Kölpin, Alexander; Vinci, Gabor; Lämmle, Benjamin; Kissinger, Dietmar; Weigel, Robert (IEEE Microwave Magazine, 2010)
Modern wireless sensing and communication systems are often based on high bandwidth and high carrier frequencies. In the range beyond 100 GHz, common receiver architectures, like active homodyne or heterodyne receivers, have an issue with the amplification needed for mixing. Also, high bandwidth is a problem for these systems. In this context, the six-port receiver is a good alternative, just as well as for lowvolume markets. The six-port concept is based on the additive superposition of the two RF input signals using four different relative phases leading to constructive or destructive interaction. The resulting signals are directly downconverted to baseband by diode circuits operated in detector or mixing mode. The complexvalued information can be easily reconstructed from the four baseband voltages. Historic evolution leads from the reflectometer approach for an alternative vector network analyzer to receivers for sensing and communications. A recent topic is the technology gap in automotive workshops for adjusting the long-range radar sensor of a car. Here, the six-port concept as alignment tool is a good choice, because of its excellent phase resolution. Currently, the integration of the six-port receiver on a MMIC for frequencies beyond 100 GHz is the focus of current work and will be intensified in the future. Will the six-port concept replace common active homodyne and heterodyne receivers? No, but it is a serious alternative for millimeter-wave frequencies and ultrahigh-bandwidth applications in wireless sensing and communication systems. This modern concept can tap new markets for both wireless sensors and sensor networks.
elib2cris::1512001600,koelpin2010a
Keywords: Antenna measurements; Bandwidth; Baseband; Digital signal processing; Mobile radio mobility management; Receivers; Wireless sensor networks

The Six-Port Structure as a Precise Measurement Tool - A New Rise of an Old Concept - Kölpin, Alexander; Lindner, Stefan; Mann, Sebastian; Barbon, Francesco; Talai, Armin; Weigel, Robert (Kleinheubacher Tagung, 2013)
Six-Port Technique has been known in RF and microwave metrology since the early 1970s for vector network analysis and precise power measurements. Two decades later, the system has been proposed as a receiver for complex valued data reception. However, six-port technique has always been niche architecture, since the tremendous evolution in integrated circuit technology got more and more impact on high-end circuitry and measurement systems. But there are some special applications that can be very efficiently addressed by the six-port principle. In general, all scenarios where the interesting information is coded in signal power or can be translated in relative phase shifts are suitable for six-port systems, as this architecture offers superior phase resolution combined with low cost implementation. Furthermore, this principle can be used up to millimeter-wave frequencies and even higher. The reason is that the core functionality is realized only by passive transmission lines or waveguide structures featuring the interferometric part, and only diodes have to be used as monolithic components for the RF front-end. The information reconstruction is conducted in baseband by algorithms with very low complexity that can be run on a low power microcontroller and show only low latency of a few controller clock cycles. In this talk the newest results for applications addressed by six-port architecture for metrology will be presented. Besides very precise distance and angle measurements or vibration analysis, like heartbeat and breath rate detection, also new fields will be presented. One very promising approach is using the six-port technique for frequency analysis of a pulse-like microwave signal. Furthermore, the very first results in temperature measurements of a water basin by a six-port reflectometer will be shown.
elib2cris::1512001600,koelpin2013c
Keywords: Six-Port; Interferometer

The Six-Port Technology: A Low-Cost Concept for Precise Position Measurements - Kölpin, Alexander; Vinci, Gabor; Barbon, Francesco; Lindner, Stefan; Fischer, Georg; Weigel, Robert (9th International Multi-Conference on Systems, Signals and Devices, 2012)
Local positioning is a demanding task for industrial environments. With the help of six-port technology, a precise and easy to use concept for angle of arrival (AoA) and distance measurements will be presented in this publication. AoA resolution below 0.005° and resolving distances of 1μm for a 24 GHz six-port architecture will be shown by measurement results. Furthermore, impairments compensation issues and limitations of the technology will be discussed.
elib2cris::1512001600,koelpin2012a
Keywords: Antenna measurements; Microwave circuits; Microwave integrated circuits; Microwave measurements; Receivers; direction-of-arrival estimation; Six-Port

The Spectrum Sensing Network: Information Acquisition for the Cognitive PMSE System - Rieß, Steffen; Brendel, Johannes; Stöckle, Andreas; Schröter, Simon; Rose, Richard; Fischer, Georg (Shaker Verlag, 2014)
Accessing the frequency spectrum in a dynamic way has been discussed since several years. The Cognitive Radio (CR) technology was identi ed as enabler in order to use the spectral resources in a more e cient way. However, to guarantee interference free operation between multiple services, spectrum sensing plays a major role of designing such a system. This contribution focuses on the realization of the Spectrum Sensing Network (SSN) that has been developed during a research project in Germany. The SSN involves multiple sensor nodes consisting of a receiver with broadband antenna which are connected to a central controller that is in charge of handling the interfaces and acquired data of the SSN. With this setup it is possible to generate an accurate radio environment map, i.e. power over frequency, time and location, in the UHF frequency range from 470 to 870 MHz. After a short introduction to the system requirements and a project overview, attention is paid to the necessary components of such a distributed sensing grid. The measurement results and the discussion of possible advantages of a SSN show the added value for a CR system. Although, the application and demonstration was based on the improvement of operating conditions for Professional Wireless Microphone Systems (PWMS), the originated eld trial platform is open for reasearch activities related to other CR systems in this frequency range.
elib2cris::1512001600,riess2014
Keywords: PMSE; cognitive radio; spectrum sensing; sensing network; sensing grid; scanning controller; scanning receiver; scanning antenna; radio environment map; data fusion

The spectrum situation for PMSE - Or why is PMSE so unique? - Fischer, Georg (PEARLE Conference, 2015)
elib2cris::1512001600,fischer2015
Keywords: PMSE; C-PMSE; UHF; CR; SDR; Multimedia

The System Design of Integrated Passive Transponder Devices - Seemann, Kay; Weigel, Robert (APMC 2006. Asia-Pacific Microwave Conference, 2006)
In order to improve the operation reliability of passive transponders (e.g. for radio frequency identification applications - RFID), the design of low-loss integrated circuits and the development of efficient energy scavenging devices are an emerging task. This article deals with general considerations regarding self-sustaining integrated transponder devices with integrated RF power rectifiers and backscatter modulators. We present important fundamentals and limitations of the passive integrated RF frontend architecture.
elib2cris::1512001600,seemann2006b
Keywords: Integrated circuit reliability; passive networks; transponders; backscatter modulators; integrated RF power rectifiers; integrated passive transponder design; low-loss integrated circuits; passive integrated RF frontend architecture; radio frequency identification applications; self-sustaining integrated transponder devices; Backscatter; Circuit topology; Coupling circuits; Modeling; Passive RFID tags; Power system reliability; Radio frequency; Radiofrequency identification; Rectifiers; Transponders; Backscatter Modulation; Passive RFID; Passive Transponders; Ultra-Low-Power Rectifiers

The Use of Network-Parameter-Based Identification Techniques for Reduced Order EMC Modeling - Neumayer, Roland; Stelzer, Andreas; Eurskens, Wolfgang; Weigel, Robert (Proceedings of the International Symposium on Electromagnetic Compatibility, 2004)
elib2cris::1512001600,neumayer2004a

Thinking small: next-generation sensor networks close the size gap in vertebrate biologging - Ripperger, Simon; Carter, Gerald; Page, Rachel; Duda, Niklas; Kölpin, Alexander; Weigel, Robert; Hartmann, Markus; Nowak, Thorsten; Thielecke, Jörn; Schadhauser, Michael; Robert, Jörg; Herbst, Sebastian; et al. (Plos Biology, 2020)

Time domain phase noise synthesis for system simulation - Yang, L.; Yue, J.; Ehm, Henning (49th IEEE International Midwest Symposium on Circuits and Systems, 2007)
In order to verify the system performance of large-scale integrated chip sets for wireless applications, models are required to synthesize phase noise in discrete time. This paper proposes a scheme that generates phase noise in the time domain with a simple white noise input and is parameterized by quantities whose value can be adjusted to reflect the desired phase noise parameters. Furthermore, it allows selecting different combinations of noise frequency response in different frequency bands. Therefore, the noise measured in the laboratory from test chips can be easily simulated for verification of system performance. The MATLAB simulation environment was selected because of its wide application for development and evaluation of communication algorithms.
elib2cris::1512001600,yang2007

Time-Domain Simulation of Low-Reflection Broadband Coplanar Waveguide Tapers and Circular Bends - Isele, Bertram; Thomann, Wolfgang; Stöckeler, F.; Weigel, Robert; Russer, Peter (Proc. Progress in Electromagnetics Research Symposium, 1993)
elib2cris::1512001600,isele1993

Time-Efficient Adjacent Channel Power Ratio Simulation utilizing Overlap-add Signal Decomposition for UMTS Power Amplifiers - Zohny, Amr; Leuschner, Stephan; Kastner, M.; Rascher, Jochen; Ußmüller, Thomas; Müller, Jan-Erik; Fischer, Georg; Weigel, Robert (Asia-Pacific Microwave Conference - APMC 2012, 2012)
The suitability of an RF power amplifier (PA) for modern sophisticated modulation schemes demands high linearity. One of the most significant figures of merit concerning PA linearity is its adjacent channel power ratio (ACPR). The aim of this paper is to propose a time-efficient simulation procedure for ACPR which conforms with the latest 3GPP TS 25.101 specifications for its calculation. This procedure overcomes the time penalty associated with the traditional envelope-based simulation method. The approach is based on standard harmonic balance (HB) tools with MATLAB post-processing incorporating the Overlap-add (OLA) signal decomposition DSP technique for fast RRC filtering. In addition, the simulation results are compared with measurements of a commercial WCDMA PA for verification. Accuracies of better than 0.5dB and 1.1dB are achieved up to 10dB and 2dB backoff respectively.
elib2cris::1512001600,zohny2012b
Keywords: Power Amplifier; Linearity; ACPR; WCDMA; Distortion; Harmonic Balance

Time Signal Assisted GPS Receiver for Mobile Devices - Kandziora, Christoph; Weigel, Robert (Proceedings of the 23rd International Technical Meeting of The Satellite Division of the Institute of Navigation, 2010)
This paper presents a novel concept for a GNSS receiver for mobile devices based on the single-shot receiver concept. In comparison to the common single-shot receiver the amount of computational hardware is significantly reduced by an estimation of the time of signal reception. This allows an a-priori estimation of the code-phase of the satellites in view. The synchronization to the time code signal must be better than 1 ms for GPSIn- Orbit-Vehicles (IOVs) to take effect which is here realized by using the German DCF77 signal with a precision of 250 ns under ideal circumstances. Regarding all uncertainties in time and the amount of signal processing power required for the time synchronization the computational effort for the advanced single-shot receiver can be cut down by a factor of two.
elib2cris::1512001600,kandziora2010

Time Synchronization of Spatial Separated Areas for AV-Production - Bruckmeyer, Heiko; Bühlmeyer, Jonas; Ackermann, Thomas; Fischer, Georg (2021 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS), 2021)

Timing Deviations in Wireless Networks using Bluetooth Periodic Advertising - Maiwald, Timo; Zhang, Qing; Bartunik, Max; Shi, Kilin; Lurz, Fabian; Fischer, Georg; Ackermann, Thomas (2022 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2022)
Monitoring and control systems, including spatially distributed devices, often require simultaneous responses to control commands. Especially when timing is crucial a synchronized connection between all devices is necessary to minimize differences in response time. This paper introduces a method which uses Bluetooth periodic advertising to establish a wireless synchronized multicast to simultaneously control devices. Results of time difference measurements between two devices, reacting on control commands received by the same periodic advertising packet, are introduced and discussed using large scale experimental data. Device configurations, where an impact on timing was experienced, are presented. Time difference values with a low maximum delay of 11 μs were achieve
Keywords: Periodic Advertising; Bluetooth; Wireless Synchronization

Timing of the FFT-Window in SC/FDE Systems - Koppler, Alois; Huemer, Mario; Springer, Andreas; Weigel, Robert (4th International Workshop on Multi-Carrier Spread-Spectrum, 2003)
elib2cris::1512001600,koppler2003b

Tire Pressure and Temperature Radio Sensor Based on SAW Transponder Technique - Schimetta, Gernot; Scholl, Gerd; Weigel, Robert (Proc. IEEE International Workshop onCommercial Radio Sensing and Communication Techniques, 2001)
elib2cris::1512001600,schimetta2001b

Tire pressure measurement using a SAW hybrid sensor - Schimetta, Gernot; Dollinger, Franz; Weigel, Robert (XVI IMEKO (International Measurement Confederation) World Congress, 2000)
A tire pressure measuring system based on surface acoustic wave (SAW) sensors is presented. Since SAW sensors are powered by the energy of the RF field no battery is required, which is a major drawback of conventional systems. A successful combination of a SAW reflective delay line with a capacitive pressure sensor is shown. With a new way of matching the sensor impedance to the SAW reflector impedance both a high signal-to-noise ratio and a high signal dynamic are achieved which supports accurate signal evaluation. A prototype of a tire pressure sensor unit is presented.
elib2cris::1512001600,schimetta2000b
Keywords: SAW; trie pressure sensor; wireless remote sensing

To-Code-Or-Not-To-Code in a Single-Carrier System with Frequency Domain Equalization - Witschnig, Harald; Aichberger, Roland; Groh, Thomas; Weigel, Robert; Springer, Andreas (Proc. ITG-Conference on Source and Channel Coding, 2004)
elib2cris::1512001600,witschnig2004

Touch-Free Industrial Vibration Monitoring System - Kölpin, Alexander (Workshop Proceedings on Advanced mm-Wave Circuits and Systems for Emerging Radar Applications, 2018)
Keywords: Six-port; Radar; Interferometer; Vibration

Toward Magnetic Localization of Capsule Endoscopes during Daily Life Activities - Zeising, Samuel (FAU-Networking Night Medizintechnik (Poster Presentation), 2021)

Toward Magnetic Localization of Capsule Endoscopes during Daily Life Activities - Zeising, Samuel; Thalmayer, Angelika; Fischer, Georg; Kirchner, Jens (Kleinheubacher Tagung 2021, 2021)

Towards Broadband D-Band Wireless Communication Systems using Beam Steering in SiGe BiCMOS Technology - Maiwald, Tim; Kolb, Katharina; Potschka, Julian; Dietz, Marco; Weigel, Robert (GSMM 2021 - 2021 Global Symposium on Millimeter-Waves and Terahertz, Proceedings, 2021)
This paper provides an overview of key challenges and solutions for integrated circuits and system-integration in order to realize practical mm-wave wireless communication systems in D-band targeting data rates in the order of 100 Gbps with beam steering functionality. As key element for beam-controlled systems, the design and measurement results of a broadband, low power and digitally adjustable D-band phase shifter are presented. Additionally, system performance limits in different beam-steering architectures are derived. The presented vector modulator core exploits passive phase generation with synthesized high performance couplers, achieving a 360° phase control at a maximum power consumption of 25mW from a 2.5V supply and a maximum 3 dB bandwidth of 20 GHz. Because of its flat gain response and high control-resolution, the phase shifter can be operated within multiple multi-GHz sub-bands within the D-band.
CRIS-Team Scopus Importer:2021-09-10
Keywords: Beyond 5G; Communication; D-band; Phase shifter

Towards Differential Static Magnetic Localization of Commercial Capsule Endoscopes: An Evaluation Using Different Ring and Cylindrical Magnets - Zeising, Samuel; Chen, Lu; Thalmayer, Angelika; Fischer, Georg; Kirchner, Jens (Advances in Radio Science : Kleinheubacher Berichte, 2023)

Towards Embedded Radcom-Sensors in Wind Turbine Blades: Preliminary Numerical and Experimental Studies - Simon, Jonas; Moll, Jochen; Krozer, Viktor; Kurin, Thomas; Lurz, Fabian; Weigel, Robert; Krause, Stefan; Bagemiel, Oliver; Nuber, Andreas; Issakov, Vadim (Progress in Electromagnetics Research Letters, 2020)
This paper presents a numerical study on the application of radar and communication (RadCom) sensor nodes operating in the frequency band from 57-64 GHz. The sensor nodes are embedded in the laminate of wind turbine blades, enable a quality inspection directly after rotor blade manufacturing as well as a structural health monitoring (SHM) throughout the service life of the blade. Given by a lack of dielectric properties for typical rotor blade materials, we have performed experimental studies on material characterization including glass fibre composites, balsa wood, infusion glue, etc. This material database serves as input for wave propagation simulations in a full scale 3D rotor blade model. The analysis also includes a parametric study on path losses as well as an optimal sensor placement strateg

Towards Future Automotive Safety Applications based on Phased Array FMCW-Radar Sensors – a Holistic Simulative Approach Incorporating RF-Frontend Impairments - Dudek, Manuel (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2015)

Towards Realisation of a Non-Invasive Blood Glucose Sensor Using Microstripline - Zeising, Samuel; Kirchner, Jens; Fazeli Khalili, Hossein; Ahmed, Doaa; Lübke, Maximilian; Thalmayer, Angelika; Fischer, Georg (International Instrumentation and Measurement Technology Conference (I2MTC), 2020)

Towards Steering Magnetic Nanoparticles in Drug Targeting Using a Linear Halbach Array - Thalmayer, Angelika; Zeising, Samuel; Lübke, Maximilian; Fischer, Georg (Advances in Radio Science : Kleinheubacher Berichte, 2023)

Track-before-detect short range radar system for industrial applications - Reißland, Torsten; Sporer, Michael; Scheiner, Benedict; Pflaum, Felix; Hagelauer, Amelie Marietta; Weigel, Robert; Lurz, Fabian (2020 IEEE Topical Conference on Wireless Sensors and Sensor Networks, WiSNeT 2020, 2020)
This paper presents a multiplexed short range frequency modulated continuous wave (FMCW) radar system and an algorithmic approach for the detection of targets. The algorithm uses a heuristic particle filter to track potential targets before they are actually detected. The detection algorithm is compared to a well-known constant false alarm rate (CFAR) detector. The whole setup is tested on real-life data in an industrial scenario.
CRIS-Team Scopus Importer:2020-04-17
Keywords: Detection; Industrial; Radar; Track before detect

Tracking the Traveled Distance of Capsule Endoscopes along a Gastrointestinal-Tract Model Using Differential Static Magnetic Localization - Zeising, Samuel; Chen, Lu; Thalmayer, Angelika; Lübke, Maximilian; Fischer, Georg; Kirchner, Jens (Diagnostics, 2022)

Trade-off analysis of decoding algorithms and architectures for multi-standard LDPC decoder - Priewasser, R.; Huemer, Mario; Bougard, B. (IEEE Workshop on Signal Processing Systems, 2008)
Since Low-Density Parity-Check (LDPC) codes deliver excellent decoding performance, they are adopted in several recent communication standards like the IEEE 802.11n, IEEE 802.16e and DVB-S2. This raises the need for multi-standard, multi-mode decoder architectures. In this paper we propose to use the min-sum approximation together with a turbo-like decoding approach for decoding LDPC codes, and afterwards we perform a global trade-off analysis which enables the designer to choose the appropriate decoding algorithm.
elib2cris::1512001600,priewasser2008

Transceiver Architectures for W-CDMA Mobile Terminal Applications. - Thomann, Wolfgang; Fenk, Josef; Hagelauer, Richard; Weigel, Robert (Elektrotechnik und Informationstechnik, 2003)
Eligible transceiver architectures for third-generation Wide-Band Code Division Multiple Access (W-CDMA) mobile terminal application are presented. The heterodyne, homodyne, and low-IF architecture are discussed in detail with respect to their specific properties regarding W-CDMA. The considered issues include topics like system requirements, technical performance parameters, integration level possibilities as well as general topics like system cost and development effort.
elib2cris::1512001600,thomann2003
Keywords: W-CDMA; UMTS; Transceiver; Architekturen; Heterodyn; Homodyn

Transceiver-Module Design in Flip-Chip Technology at Milimeter-Wave Frequencies - Nagy, Oliver; Heide, Patric; Weigel, Robert (Proc. IEEE International Workshop on Commercial Radio Sensing and Communication Techniques, 2001)
elib2cris::1512001600,nagy2001

Transceiver Setup for Joint Communication and Sensing Applications in V-Band - Faghih-Naini, Samira; Peters, Sebastian; Kurin, Thomas; Erhardt, Stefan; Reißland, Torsten; Weigel, Robert (IEEE Radio and Wireless Symposium (RWS), 2023)
A new transceiver setup for joint communication and sensing (JCAS) application in V-band with a 3 dB bandwidth of 2.57GHz is presented in this work. With new communication standards like 6G and a rising amount of wireless transmitted data, new transceiver setups for higher carrier frequencies and larger bandwidth need to be developed. The new transceiver setup has differential IQ input ports and a carrier frequency ranging from 57 GHz to 64 GHz. For the proof of radar and communication applications, the reflected IQ signal was detected, and the usability confirmed. This setup can be used for JCAS applications in meter range with high resolution and data rates. <br
Keywords: millimeter wave circuits; millimeter wave communication; millimeter wave radar; transceiver

Transcutaneous Energy Transfer System for Cardiac-Assist Devices by Use of Inhomogeneous Biocompatible Core Material - Fazeli Khalili, Hossein; Kirchner, Jens; Bartunik, Max; Werner, Siegfried; Ebel, Nina; Schubert, Dirk W.; Weyand, Michael; Fischer, Georg (IEEE Transactions on Magnetics, 2021)
A novel magnetic liquid silicone rubber composite core design applicable to wireless power transfer (WPT) for medical applications is presented. As a case study, the integration of WPT, including the proposed cores for the coils, with ventricular assist devices (VADs) was investigated. This facilitates transferring 4.6 W of power wirelessly through the skin-layer, which thus allows to disposal of the transcutaneous cable that connects the extracorporal batteries to the implanted blood pump. To enhance the coupling coefficient and consequently increase the WPT efficiency, the geometry of the cores was optimized. This reduces the temperature increase in the implant area. The field and thermal simulations were carried out with CST software. The electrical properties of the proposed design as obtained by simulation were validated by measurements. The simulation results perfectly coincide with the measured results. Finally, a new optimized design with additional high permeability core inserts is introduced to further increase the coupling coefficient. The results indicate that the coupling coefficient is increased from 0.31 to 0.52 with the optimized design compared to the case without cores. Moreover, by fixing the initial temperature as 37 °C, the maximum temperature is decreased from 38.19 °C to 37.27 °C, while keeping the transferred power fixed. Its high magnetic conductivity, biocompatibility, low-loss property, flexibility and Qi-standard compatibility make the proposed WPT design an excellent candidate for the wireless-powering of heart assist devices such as VAD

Transformation from Voltage-Mode to Current-Mode: an Alternative Approach - Koca, Özhan; Yang, X.; Weigel, Robert (14th International Conference on Electronics, Circuits and Systems, 2007)
elib2cris::1512001600,koca2007b

Transformer-based 24 GHz Power Amplifier in 65nm CMOS Technology for FMCW Applications - Muharemovic, Nedim; Bauch, Andreas; Hagelauer, Amelie Marietta; Weigel, Robert (2019 IEEE RADIO AND WIRELESS SYMPOSIUM (RWS), 2019)
CRIS-Team WoS Importer:2019-06-25

Transformer-Coupled D-Band PA with 11.8 dBm Psat and 6.3 % PAE in 0.13 μm SiGe BiCMOS - Romstadt, Justin; Lammert, Vincent; Pohl, Nils; Issakov, Vadim (2020 IEEE 20th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems, SiRF 2020, 2020)
In this paper we present a fully differential power amplifier (PA) in a 0.13 μm SiGe BiCMOS technology operating in D-Band. The PA has a maximum PAE of 6.3 %, a saturated output power of 11.8 dBm at a frequency of 114 GHz and is designed to an optimum load impedance different from 50 Ω offered by a chip to PCB transition. In the previously designed SiGe BiCMOS PAs for D-Band applications, interstage matching networks consist of transmission lines, whereas in this work a transformer is used because a transformer offers the advantage of being an efficient and compact higher-order filter. Therefore, the amplifier only occupies an active chip area of 0.19 mm2 including baluns. In CMOS transformer-based coupling between the stages is quite common, whereas in SiGe this has not been demonstrated so far. Accordingly, to the authors best knowledge, this is the first D-Band SiGe PA using transformer-coupling.
CRIS-Team Scopus Importer:2020-04-24
Keywords: D-Band; HBT; Millimeter wave circuits; Power amplifier (PA); Silicon germanium (SiGe); transformer

Transformer-Coupled Octa-Core 60 GHz Push-Push VCO in a 45-nm RF-SOI CMOS Technology - Rimmelspacher, J.; Weigel, Robert; Issakov, V. (2019 IEEE International Conference on Microwaves, Antennas, Communications and Electronic Systems, COMCAS 2019, 2019)
This work presents a 60 GHz octa-core push-push VCO in a 45 nm partially depleted (PD) Silicon-on-Insulator (SOI) CMOS technology. We investigate the feasibility of coupling eight VCO cores via resonant-tank transformers and discuss circuit topology considerations. The measured phase noise at 63.4 GHz is -95.3dB/Hz at 1 MHz offset from carrier. The continuous frequency-tuning range is 19 %. The eight VCO cores consume in total 80 mW DC power. The complete circuit, including buffers at the fundamental and second harmonic outputs, draws 158 mA from a single 1 V supply. The total area of the octa-core VCO excluding pads is 0.18 mm2.
CRIS-Team Scopus Importer:2020-02-21
Keywords: CMOS technology; millimeter-wave; phase noise; silicon-on-insulator; VCO; wideband

Transmission Line Filters with High-Tc Superconductors - Valenzuela, Alejandro; Daalmans, B.; Weigel, Robert; Nalezinski, Martin; Russer, Peter (Proc. of the Workshop on Microwave Devices with High Temperature Superconductors, 1992)
elib2cris::1512001600,valenzuela1992

Transmission-Line High- Efficiency Low Voltage InGaP/GaAs HBT Power Amplifier for 3G Cellular Phone Transmitters - Jäger, Herbert; Grebennikov, Andrej; Weigel, Robert (European Microwave Conference, 2002)
elib2cris::1512001600,jaeger2002a

Transmitter Leakage Cancellation in Cellular Handset Receivers - Elmaghraby, Ahmed (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2016)

Trends and technologies for frequency agile communication systems - Fischer, Georg; Eckl, Wolfgang (Mikrowellen Workshop, 2005)
elib2cris::1512001600,fischer2005b

Trends and Technologies for mobile communication systems - Fischer, Georg; Eckl, Wolfgang (Radar and Communication (RADCOM 2006), 2006)
elib2cris::1512001600,fischer2006b

Trends bei integrierten Hochfrequenzschaltungen - Weigel, Robert (Tagung Mikrowellen – Prozesse und Anwendungen in der Werkstoff- und Nachrichtentechnik, 2003)
UnivIS-Import:2015-04-16:Pub.2003.tech.IE.LETE.trends
Keywords: Invited Paper

Trends in Basestation RF Technology - Fischer, Georg (German Microwave Conference (GeMiC 2006), 2006)
elib2cris::1512001600,fischer2006d

Triggering UMTS user equipment inter-RAT cell reselection using noise jammers - Gardill, Markus; Zorn, Stefan; Weigel, Robert; Kölpin, Alexander (German Microwave Conference, 2011)
In this work a strategy for triggering an interradio access technology cell reselection in UMTS user equipment is proposed. All mobile devices within the effective range of a transmitter radiating a noise-like RF signal on the UMTS downlink frequency bands are forced to leave the UMTS cells and camp on non-UMTS cells, such as e.g., GSM. This allows to use a GSM based localization technique even in areas with UMTS coverage. In contrast to classical RF communication jammers which focus on disrupting the communication link, our exclusive goal is to trigger the inter-RAT cell reselection to GSM. In particular we estimate the necessary jammer RF power by examining the cell reselection procedure running in the user equipment (UE) and using some exemplary geographical scenarios. We use a hardware system to proof the results. Index Terms IEEE Terms 3G mobile communication , GSM , Interference , Jamming , Mobile handsets , Noise , Radio frequency INSPEC Controlled Indexing 3G mobile communication , cellular radio , jamming , radio links , radio transmitters Non Controlled Indexing GSM based localization , RF communication jammer , UMTS cell , UMTS coverage , UMTS downlink frequency band , UMTS user equipment , communication link , geographical scenario , interRAT cell reselection , interradio access technology , jammer RF power , mobile device , noise jammer , noise-like RF signal , transmitter Author Keywords UMTS , cell reselection , jammer References S. Zorn, R. Rose, A. Goetz, and R. Weigel, "A novel technique for mobile phone localization for search and rescue applications," in 2010 International Conference on Indoor Positioning and Indoor Navigation (IPIN), Sep. 2010, pp. 1-4. Abstract |Full Text: PDF (1079KB) User Equipment (UE) procedures in idle mode and procedures for cell reselection in connected mode, 3rd Generation Partnership Project Std. TS 25.304, Rev. 9.0.0, 2009. Physical layer - Measurements (FDD), 3rd Generation Partnership Project Std. TS 25.215, Rev. 9.0.0, 2009. S.-F. Su, The UMTS air-interface in RF engineering: design and operation of UMTS networks. Mcgraw-Hill Professional, 2007. ON THIS PAGE Abstract Index Terms References Brought to you by Universitatsbibliothek Erlangen Nurnberg Your institute subscribes to: IEEE/IET Electronic Library (IEL), VDE VERLAG Conference Proceedings What can I access? Terms of Use
elib2cris::1512001600,gardill2011

Tunable BST-Varactor-Based Matching Networks for Mobile Radio Applications - Lourandakis, Errikos; Schmidt, Matthias; Weigel, Robert (IEEE International Microwave Symposium, 2008)
elib2cris::1512001600,lourandakis2008b

Tunable Lumped Element Filters With BST Thin-Film Varactors - Lourandakis, Errikos; Schmidt, Matthias; Seitz, Stefan; Weigel, Robert (European Microwave Conference, 2008)
Tunable lumped element filter topologies are discussed based on ferroelectric thin-film varactors. The design methodology for the proposed filter topologies relies on already known techniques and is enhanced with the tuning functionality by introducing the Barium-Strontium-Titanate (BST) varactors. Prototype circuits of a lowpass and a bandstop filter were fabricated and the measurement results showed good agreement to the corresponding calculated data. The lowpass prototype achieves a continuous tuning range from 1.5 GHz to 1.9 GHz. The highest measured passband insertion loss is about 4 dB and the input matching is better than -15dB for all bias states. The implemented bandstop filter allows a continuous tuning of the notch frequency from 1.5 GHz to 2.1 GHz with a minimum attenuation of 17 dB.
elib2cris::1512001600,lourandakis2008c

Tutorial on Introduction to UMTS - Weigel, Robert; Springer, Andreas; Pimingsdorfer, Dieter; Eichinger, Ludwig (ASCOM Business Systems, 2000)
elib2cris::1512001600,weigel2000b

Two-dimensional Angle-of-arrival Analysis by One Enhanced Six-port Structure - Kölpin, Alexander; Lindner, Stefan; Mann, Sebastian; Barbon, Francesco; Linz, Sarah; Weigel, Robert (Progress In Electromagnetics Research Symposium (PIERS), 2013)
elib2cris::1512001600,koelpin2013a

Two improving methods of eog-based eye movement detection for HCI - Chen, Minghui; Anzai, Daisuke; Wang, Jianqing; Terado, Toshihiko; Fischer, Georg (IEEJ Transactions on Electronics, Information and Systems, 2019)
In this paper, we proposed two methods to reduce the errors that happens during Electrooculogram(EOG)-based eye movement detection, especially in the case of EOG-based input system or Human-Computer-Interface (HCI). The first one is about taking measures in the detection algorithm, and the second one is by employing the Posner paradigm. Their validity was experimentally evaluated and the results show that our approaches can improve the accuracy of EOG-based eye movement detection by about 10%.
CRIS-Team Scopus Importer:2019-12-17
Keywords: Biosignal sensing; Electrooculogram; Electrooculography; EOG; Eye movement detection; Posner paradigm

Two-track-reflector-filters for CDMA mobile telephones - Bergmann, Andreas; Machui, Jürgen; Wagner, Karl Christian; Weigel, Robert (IEEE International Ultrasonics Symposium (IUS), 1996)
IF-filters for channel selection in mobile phones based on a CDMA system must offer very steep skirts as well as excellent phase linearity and small amplitude ripple within the passband. To fulfill all these requirements a conventional transversal surface acoustic wave (SAW) filter needs a large chip size. In order to reduce the total chip length we folded the propagation path of the SAW taking advantage of the reflector filter technique. Therefore, the usable time window for weighting becomes almost twice as large. We employed weighted reflectors not only to reflect the SAW but also to shape the filter frequency response. Thus we have more flexibility to design the transducers. We can make them shorter but still have lower impedances on quartz than with an unweighted reflector design. With this technique, we built filters at a center frequency of 110 MHz with an insertion attenuation of less than 15 dB, a 5 dB bandwidth of 1.26 MHz and an attenuation of more than 30 dB outside of a 1.80 MHz band. The chip is mounted in a 15.6×6.8 mm2 SMD package. The reflector filter fulfills the frequency response specification required for CDMA mobile telephones on a chip length reduced by about 4 mm compared with the transversal or SPUDT design technique
elib2cris::1512001600,bergmann1996

UAV-based Localization of Mobile Phones for Search and Rescue Applications - Dorn, Christian; Depold, Andreas; Lurz, Fabian; Erhardt, Stefan; Hagelauer, Amelie (2022 IEEE 22nd Annual Wireless and Microwave Technology Conference, WAMICON 2022, 2022)
In this work a system is proposed that utilizes an unmanned aerial vehicle (UAV) to search and rescue trapped victims using their mobile phones. The systems consists of two parts, a ground station (GS) and an airborne station (AS). The GS provides a downlink to the UAV, a GSM base station along with antenna equipment and a mobile network jamming device. By using a smart approach to block the synchronization sequences of all base stations in range, the mobile phones of the victims to be located are switching to an emergency fallback mode. In this mode the phones connect to the strongest base station in range, thus the one provided by the GS. By initiating a call to the corresponding phone the AS can localize it using direction-of-arrival detection with a 9-channel phase coherent receiver system.
CRIS-Team Scopus Importer:2022-07-15
Keywords: dar; Jammer; Sar; uav

Überwachungskonzepte für sicherheitsrelevante Funktionen auf Basis automobiler Radarsensoren - Schnabel, Raik (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2014)

Ueberblick 6-Tor Technologie in der Positionstechnik - Kölpin, Alexander (Electrical and Electronic Engineering for Communication Workshop - Entwicklerforum - Fachmesse, 2012)
elib2cris::1512001600,koelpin2012c

ULPSEK – Ultra-Low-Power Sensor Evaluation Kit - Tobola, Andreas; Rybalko, Ruslan; Korpok, Oliver; Streit, Franz J.; Espig, Chris; Hofmann, Christian; Schmitz, Björn; Struck, Matthias; Weigand, Christian; Fischer, Georg (FOCUS Session "Wearable Sensors", BMT, 2015, 2015)
elib2cris::1512001600,tobola2015b

Ultrabreitbandiges Funksystem für die Übertragung von Signalen von Fahrzeug-Kameras - Terzis, Anestis (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2011)

Ultra-Broadband Millimeter-Wave Circuits and Systems in Silicon-Germanium Technology - Nasr, Ismail (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2014)

Ultra-compact TDLAS humidity measurement cell with advanced signal processing - Hartmann, Alexander; Strzoda, Rainer; Schrobenhauser, Robert; Weigel, Robert (Applied Physics B-Lasers and Optics, 2014)
In this paper, tunable diode laser absorption spectroscopy humidity measurements with an ultra-compact measurement cell are presented. The optical path length is 2 cm. The system uses a vertical cavity surface emitting laser at 1.854 μm. The main limiting factor of the humidity resolution is not the noise but interference fringes produced by reflecting surfaces. Next to the system setup, a novel rejection method to eliminate these fringes, based on Fourier domain analysis of the absorption line, is described. In contrast to other fringe rejection methods, the presented method is able to handle fringes, whose free spectral range is in the range of the half width of the absorption line. The achievable humidity resolution for the presented cell is below 0.25 % relative humidity at room temperature.
elib2cris::1512001600,hartmann2014a

Ultra High Speed Wireless Communication: Approaches and Ideas to Achieve Wireless 100 Gb/s Communication (W19) - Low-Power System Architectures for Future 100 Gb/s Wireless Communication Systems - Kissinger, Dietmar; Vossiek, Martin; Berroth, Manfred; Ellinger, Frank (43th European Microwave Week, 2013)
UnivIS-Import:2015-04-16:Pub.2013.tech.IE.LEH.ultrah

Ultra-Low Power 60 GHz Class-C Frequency Tripler in 22-nm FDSOI CMOS Technology - Gupta, Aditya; Dietz, Marco; Engelmann, Andre; Hagelauer, Amelie (Latin America Symposium on Circuits and Systems 2024 (LASCAS2024), 2024)
This paper presents a 60 GHz class-C frequency tripler, implemented in 22-nm FDSOI (fully depleted silicon- on-insulator) CMOS technology, for ultra-low power and highly integrated radios used in millimeter-wave indoor localization ap- plications. The tripler employs a multi-stage transformer-coupled differential design with band-pass filters to selectively extract and amplify the power at the 3rd harmonic (3f0) tone while attenuating powers at fundamental (f0) and second harmonic (2f0) tones. An integrated bias generator with resistor trimming, improves the tripler robustness to the on-chip process and mismatch variations. The tripler exhibits a maximum conversion gain (CG) and peak conversion efficiency (CE) of -0.7 dB and 12.63%, respectively, at 60 GHz, and a 3-dB bandwidth of 3.6 GHz with a total DC power consumption (PDC) of 7.9 mW at 0.8 V supply. A harmonic rejection ratio (HRR) exceeding 45 dB for fundamental and second harmonic tones is achieved. The maximum saturated output power (PSAT) obtained is 0.9 dBm. The circuit occupies 0.4 mm² area, including pads.
https://cris.fau.de/converis/publicweb/Publication/318350939
Keywords: CMOS process; FDSOI; frequency multiplier; localization; millimeter wave integrated circuits

Ultra Low Power Local Positioning Systems for Wireless Sensor Networks - Eickhoff, Ralf; Ellinger, Frank; Ziroff, Andreas; Ußmüller, Thomas; Hüttner, Jörg; Gierlich, Roland; Wehrli, Silvan; Huemer, Mario (ICT-MobileSummit, 2008)
elib2cris::1512001600,eickhoff2008c

Ultra low power oscillator for UHF RFID transponder - Cilek, Fatih; Seemann, Kay; Brenk, Daniel; Essel, Jochen; Heidrich, Jürgen; Weigel, Robert; Holweg, Gerald (IEEE International Frequency Control Symposium, 2008)
This paper presents a realization of an ultra low power ring oscillator in 0.14 mum bulk CMOS technology. The application field for this oscillator is the clock generation for a baseband processor of a passive ultra high frequency (UHF) radio frequency identification (RFID) transponder. This technology will play an important role in the field of automatic identification. The paper contains simulation and measurement results for tuning range, cycle to cycle jitter and power consumption with regarding to the control current and supply voltage. The circuit was designed and fabricated by using 0.14 mum bulk CMOS technology.
elib2cris::1512001600,cilek2008

Ultra-Low Power Radar Based Presence Detection - Lurz, Fabian; Kölpin, Alexander (European Microwave Week (EuMW), Worshop on Advanced mm-Wave Radar System Solutions for Industrial and Consumer Sensing Applications, 2021)

Ultra-Low-Power Sensor Node with Wake-Up-Functionality for Smart-Sensor-Applications - Pflaum, Felix; Weigel, Robert; Kölpin, Alexander (2018 IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 2018)
In this paper a complete mobile sensor node which has the ability to monitor temperature, atmospheric pressure, relative humidity, brightness and magnetic fields is presented. Very low power consumption is achieved due to deliberate component selection, on-demand-operation made possible by a low-power wake-up circuit and measurement protocol, which allows the controller, transmitter and sensors to be in a battery-saving inactive mode for most of the time. Additionally, the sensor node can also be localized within a previously calibrated area.

Ultra Low-Power Techniques for Sensor-Enhanced RFID Tags. - Brenk, Daniel; Essel, Jochen; Heidrich, Jürgen; Weigel, Robert (IEEE MTT-S International Microwave Workshop on Wireless Sensing, Local Positioning, and RFID (IMWS2009), 2009)
This paper gives an overview on current design techniques for ultra low-power applications in passive UHF RFID tags. Specialized sensor data acquisition methods are discussed as well as generic sensor interfaces and their building blocks. Analog to digital converters working in ranges of less than 100 fJ/conversion-step are presented which can be applied as data converters for generic interfaces. Example calculations and simulations on single circuits are made to prove operability at UHF RFID conditions of only several muA available at 1 V supply voltage.
elib2cris::1512001600,brenk2009b
Keywords: UHF integrated circuits; analogue-digital conversion; data acquisition; low-power electronics; radiofrequency identification; sensors

Ultra low-profile self-matched HTCC SAW-duplexer: manufacturing and performance challenges - Koch, Robert; Bauer, Christian; Kiwitt, Jürgen; Potschi, F.M.; Weigel, Robert (IEEE International Ultrasonics Symposium, 2011)
Providing the required ability of simultaneously transmitting and receiving RF signals, duplexers are one of the key components in the well established 3G (W)-CDMA communication systems. For mobile terminals, duplexers in micro-acoustic filter technology have been used for several years. Generally, these duplexers are composed of two band pass filters and additional passive elements to improve the electrical performance. Based on the prototypical packaging approach which has been used for the recently published demonstrator of the ultra low profile self-matched SAW-duplexers we will present details of the preliminary extension of the well established Cu-frame CSSP3 packaging technology. This extension enables the integration of miniaturized planar copper coils on the top layer of an HTCC substrate. Therefore, it leads to a new miniaturization potential for the coming generations of packages for self-matched duplexers in SAW or BAW technology. Additionally, we will present some novel investigation results regarding the influence of the manufacturing process on the Q-factor. Here, the surface roughness determined by the manufacturing process and by the roughness of the HTCC at the interface of the coil and the HTCC affects the Q-factor. Including the surface roughness in the electro-magnetic simulation allows us to determine the resulting Q-factor of the planar coils very precisely. The excellent match of measured and simulated Q-factors approves this approach. Furthermore, using an EM-model with the roughness modeling for the coils, we have been able to predict the insertion loss of our filters accurately which will be demonstrated by the very good agreement of measured and simulated scattering parameters of the ultra low-profile self-matched duplexer.
elib2cris::1512001600,koch2011
Keywords: 3G mobile communication; Q-factor; bulk acoustic wave devices; code division multiple access; surface acoustic wave filters; BAW technology

Ultra low-profile self-matched SAW duplexer with a flip-chip HTCC package for W-CDMA 2100 mobile applications - Koch, Robert; Schwab, Martin; Pitschi, Maximilian; Kiwitt, Jürgen; Weigel, Robert (Microwave Symposium Digest, 2009. MTT '09. IEEE MTT-S International, 2009)
Duplexers are essential components in 3G communication systems. They provide the required duplexing functionality for simultaneously transmitting and receiving RF signals over a common antenna. Duplexers in SAW/BAW filter technology have become state-of-the-art in modern 3G mobile terminals because of their small size. Current packages for self-matched SAW/BAW duplexers are composed of several LTCC layers with embedded passive elements which are essential for the duplexing functionality. In addition, they are used for impedance matching and transfer function shaping. In this paper a new integration approach for passive elements is introduced which allows ultra low-profile packaging for self-matched SAW/BAW duplexers. Therefore, miniaturized planar inductors with high Q-factors were patterned on the top of an HTCC substrate instead of the traditional realization inside an LTCC layer stack. We will present a first characterization by simulation and measurement of these inductors. Additionally, we will present a first prototypical self-matched W-CDMA 2100 SAW duplexer with a flip-chip HTCC package based on the new packaging technology. We have integrated spiral inductors with a height of 40 mum, a line spacing of 40 mum and a line width of 40 mum on the top side of an HTCC substrate inside the package. The resulting 2520 package has a typical height of 450 mum. The first measured demonstrators show a very good Tx-Rx isolation (-52 dB in both bands), out-of-band selection (Tx@Rx-Band -47 dB, Rx@Tx-Band -55 dB), and matching (at all ports <-11 dB). The presented characterization by measurement and simulation shows a very good agreement.
elib2cris::1512001600,koch2009
Keywords: Filters; Impedance matching; Multiaccess communication; Surface Acoustic waves

Ultraschall- und mikrowellenbasierte sensorische Erfassung geringer Stoffunterschiede in wässrigen Lösungen für die medizinische Diagnostik - Schwerthöffer, Udo (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2016)

Ultra-Short-Range Precise Displacement Measurement Setup with a Near Field Slot-Line Antenna and a Dedicated Spiral Calibration - Linz, Sarah; Lurz, Fabian; Sporer, Michael; Lindner, Stefan; Mann, Sebastian; Weigel, Robert; Kölpin, Alexander (IEEE International Microwave Symposium, 2015)
This work introduces a precise measurement setup for displacement analysis in the near field of a tapered slot-line antenna from 0mm up to 20mm distance. Enhanced accuracy is achieved by a dedicated spiral reconstruction algorithm accounting for the near field effects. Moreover, the precision of the system in the micrometer range is guaranteed by four synchronous 24 bit analog-to-digital converters and a decimation factor of 10, leading to an overall update rate of 1 kHz.
elib2cris::1512001600,linz2015a

Ultra-short-range radar for precise industrial positioning - Linz, Sarah; Lurz, Fabian; Weigel, Robert; Kölpin, Alexander (Kleinheubacher Tagung 2018, 2018)

Ultra-wideband active array imaging for biomedical diagnostics - Hein, Matthias; Helbig, Marko; Kmec, Martin; Sachs, Jürgen; Scotto di Clemente, Francesco; Stephan, Ralph; Hamouda, Mohammed; Ußmüller, Thomas; Weigel, Robert; Robens, Markus; Wunderlich, Ralf; Heinen, Stefan (IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, 2012)
Ultra-wideband active array imaging has proven extremely valuable for biomedical diagnostics. At the same time, the underlying technologies have achieved a high degree of maturity. Across institutions, we have merged our expertise in M-sequence radar systems, antennas, low-noise and high-power circuitry, to devise an UWB MIMO radar system for breast tumour localisation. Recent progress in UWB imaging and hardware for active antenna arrays is presented.
elib2cris::1512001600,hein2012

Ultra-wideband compressed sensing radar based on pseudo-random binary sequences - Guarin Aristizabal, Gustavo Adolfo; Gardill, Markus; Weigel, Robert; Fischer, Georg; Kissinger, Dietmar (German Microwave Conference, 2015)
elib2cris::1512001600,guarin2015

Ultra Wide Band Low-Power Amplifier Integrated on Miniaturized Antenna for Biomedical Applications - Hamouda, Mohammed; Scotto di Clemente, Francesco; Hein, Matthias; Fischer, Georg; Weigel, Robert; Ußmüller, Thomas (European Radar Conference (EuRAD), 2013)
elib2cris::1512001600,hamouda2013

Ultra-wideband object characterization via A-scan - Oßberger, Gerald; Buchegger, Thomas; Pourvoyeur, Klaus; Schimbäck, Erwin; Stelzer, Andreas; Weigel, Robert (IEEE Conference on Ultra Wideband Systems and Technologies, 2003)
elib2cris::1512001600,ossberger2003b

Ultra Wide Band Power Amplifier for Miniaturized Antennas - Hamouda, Mohammed; Fischer, Georg; Weigel, Robert; Ußmüller, Thomas (International Wireless Symposium (IWS), 2014)
elib2cris::1512001600,hamouda2014
Keywords: UWB; amplifier

Ultra-Wideband Radio Technologies for Communications, Localization and Sensor Applications - Eßwein, Alexander; Carlowitz, Christian; Weigel, Robert; Vossiek, Martin (Ultra-Wideband Radio Technologies for Communications, Localization and Sensor Applications, 2013)
UnivIS-Import:2015-04-20:Pub.2013.tech.IE.LEH.ultraw

Ultra-Wideband Small Antenna Subarray Module with Narrow Elevation Pattern - Gardill, Markus; Schneider, J.; Oesterle, Florian; Fischer, Georg; Weigel, Robert; Kölpin, Alexander (IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, 2013)
We propose an integrated small ultra-wideband antenna subarray module with narrow elevation pattern for future use in antenna arrays providing spatial processing capabilities such as Direction-Of-Arrival estimation in the azimuth plane, in the frequency range from 5 GHz to 8 GHz. The proposed subarray design is based on four mutually coupled Vivaldi antennas stacked on a common substrate in the E-Plane, with an element distance of delem 0;high=2. We optimize the antenna element in an infinite unit-cell stick array configuration and show that - in contrast to general believe - the truncation e ects when reducing the infinite stick-array to only four elements even reduce the total scan element reflection for broadside excitation. In addition, in contrast to most previously published E-Plane Vivaldi arrays, our design does not need a parallel-plate to microstrip balun at the feed point of each antenna element to realize an integrated planar feed network. Instead we use a novel ultra-wideband and geometrically small hybrid ring coupler to realize the array feed network directly in parallel plate technology, resulting in a low-cost, two-layer, single printed-circuit board integrated subarray module with narrow elevation pattern, operating from 5 GHz to 8 GHz.
elib2cris::1512001600,gardill2013e

Ultra-Wideband Small Modular Array Antenna Based on Column-Coupled Vivaldi Subarrays - Gardill, Markus; Weigel, Robert; Kölpin, Alexander (European Conference on Antennas and Propagation, 2014)
In this contribution an ultra-wideband small array antenna for direction-of-arrival (DOA) estimation in low-cost industrial radar applications operating in the frequency range from 5 GHz - 8 GHz is designed by using column-coupled Vivaldi subarray modules. Compared to traditional ultra-wideband antenna arrays consisting of inherently wideband antenna elements, the proposed design procedure utilizes mutual coupling (MC) across the antenna elements to reduce the antenna element size, to simultaneously improve the subarray module return loss, and to allow for relatively small element spacing in the plane of DOA estimation. In contrast to state-of-the-art tightly-coupled ultra-wideband antenna arrays consisting of a large number of very small array elements on a regular grid-spacing, the proposed solution only relies on MC across four antenna elements along each array column. It hence provides UWB characteristics with a small number of antenna elements, it can easily be interfaced with a low-cost 4-RX channel radar fronted and allows for arbitrary linear array geometries such as non-uniform element spacing optimized for DOA estimation. We characterize the array and discuss MC aspects and DOA estimation results based on measured array data.
elib2cris::1512001600,gardill2014

Ultra Wideband test set-up with a novel low-cost pulse forming network - Oßberger, Gerald; Buchegger, Thomas; Stelzer, Andreas; Springer, Andreas; Diskus, Christian; Weigel, Robert (Asia-Pacific Microwave Conference, 2003)
elib2cris::1512001600,ossberger2003a

Ultra-Wideband Transmitters based on M-Sequences for High Resolution Radar and Sensing Applications - Sewiolo, Benjamin; Lämmle, Benjamin; Weigel, Robert (Sixth Conference on Ph.D. Research in Microelectronics and Electronics, 2010)
In this paper we present a novel ultra-wideband transmitter architecture for high resolution radar and sensing applications up to 30GHz. The concept for pulse compression is based on maximal-length sequences to reduce the peak-to-average power ratio. The proposed transmitter consists of a 29-1 linear feedback shift register (LFSR) to generate the radar signal and a fully differential broadband amplifier. A variable gain control has been implemented to provide high sensitivity and decrease the dynamic range. The presented circuit architecture permits the possibility of upconversion, which drastically increases the operational flexibility of the radar system.
elib2cris::1512001600,sewiolo2010

UMTS link-level demonstrations with smart antennas - Freudenthaler, Klemens; Huemer, Mario; Maurer, Linus; Paul, Steffen; Rupp, Markus (Smart Antennas - State of the Art, 2005)
UnivIS-Import:2015-04-02:Pub.2004.tech.IE.LETE.chapte

UMTS Link-level demonstrations with smart antennas - Freudenthaler, Klaus; Huemer, Mario; Maurer, Linus; Paul, Stefan; Rupp, Markus (Hindawi Publishing Corporation, 2012)
elib2cris::1512001600,freudenthaler2012

UMTS: The Physical Layer of the Universal Mobile Telecommunications System - Springer, Andreas; Weigel, Robert (Springer-Verlag, 2002)
UnivIS-Import:2015-04-02:Pub.2002.tech.IE.LETE.umtsth
Keywords: UMTS; Physical Layer

Uncertainty analysis of deep neural network for classification of vulnerable road users using micro-doppler - Dubey, Anand; Fuchs, Jonas; Reißland, Torsten; Weigel, Robert; Lurz, Fabian (2020 IEEE Topical Conference on Wireless Sensors and Sensor Networks, WiSNeT 2020, 2020)
Unlike optical imaging, it's difficult to extract descriptive features from radar data for problems like classification of different targets. This paper takes the advantage of different neural network based architectures such as convolutional neural networks and long-short term memory to propose an end-to-end framework for classification of vulnerable road users. To make the network's prediction more reliable for automotive applications, a new concept of network uncertainty is introduced to the defined architectures. The signal processing tool chain described in this paper achieves higher accuracy than state-of-the-art algorithms while maintaining latency requirement for automotive applications.
CRIS-Team Scopus Importer:2020-04-17
Keywords: Automotive Radar; Autonomous Driving; Deep Neural Networks; Mico-Doppler; VRU Classification

Underwater Interferometric Radar Sensor for Distance and Vibration Measurement - Sporer, Michael; Lurz, Fabian; Schlücker, Eberhard; Weigel, Robert; Kölpin, Alexander (IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 2015)
With the growing application of autonomous underwater vehicles (AUV) and underwater construction, i.e. robotic manipulator and maintenance systems, there is an increasing demand on precise underwater distance sensors. In this paper we present a low–cost, short–range and contactless sensor which uses electromagnetical (EM) waves for measuring distances underwater. The measurement system is based on interferometric radar applying a six– port interferometer and using EM waves at a frequency of 2.4GHz. Measurement series in fresh water have been carried out showing an precision of below 100 µm up to a distance of 35mm with only 8dBm of transmit power. Due to the high measurement rate the system can also be employed for vibration analysis. Additionally, by connecting a commercial 2.4GHz data transceiver, it is imaginable for the system to be simultaneously used for high data rate communication between e.g. AUV and unmanned underwater platforms (UUP).
elib2cris::1512001600,sporer2015
Keywords: underwater distance sensor; interferometer

Unique Word Based Phase Tracking Algorithms for SC/FDE Systems - Huemer, Mario; Witschnig, Harald; Hausner, Josef (IEEE Global Telecommunications Conference (GLOBECOM), 2003, 2003)
In this paper we consider phase tracking algorithms for single carrier systems with frequency domain equalizers (SC/FDE), which make use of the concept of unique word (UW) blockwise extension instead of the classical concept of cyclic prefix (CP) like it is used for example in OFDM (orthogonal frequency division multiplexing). Very similar to IEEE 802.11a like OFDM systems the overall baseband processing performance of SC/FDE systems largely depends on the design of channel estimation and synchronization algorithms. Some of the synchronization tasks are very straight forward, but the algorithm developer has a lot of freedom for the design of the channel estimator, and for the design of the residual carrier frequency offset tracking procedure (which we call phase tracking). In this paper we focus on the design and performance of unique word based phase tracking algorithms, which are being compared with pilot carrier based phase tracking algorithms for IEEE 802.11a like OFDM systems.
elib2cris::1512001600,huemer2003c
Keywords: OFDM modulation; channel estimation; equalisers; radio tracking; synchronisation; wireless LAN; IEEE 802.11a; OFDM systems

Universal low-cost Transmitarray Antenna Design at 61 GHz for Beam Steering with different Feed Antennas - Frank, Martin; Lurz, Fabian; Weigel, Robert; Kölpin, Alexander (24th International ITG Workshop on Smart Antennas (WSA 2020), 2020)

Unterdrüchung von parasitären Moden in FBAR-Resonatoren - Link, Andreas (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2007)

Unterschiedliche Lichtwahrnehmung von Mensch und Tier - Werner, Daniel; Schwenzfeier-Hellkamp, Eva (Photonik-Workshop 2014 - Lichtmesstechnik in Theorie und Praxis, 2014)

Untersuchung von Anordnung, Abläufen und Methoden der Wechselbiegeprüfung - Ehlenz, Tobias; Fischer, Georg; Wittmann, Armin (Draht, 2017)

Untersuchung von Komplexitätsmaßen zur Charakterisierung kardiologischer Zeitreihen - Kirchner, Jens (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2004)

Untersuchung von LED-Retrofit-Produkten als Ersatz klassischer Glühlampen für das Einsatzgebiet städtischer Weihnachtsbeleuchtung - Werner, Daniel; Schwenzfeier-Hellkamp, Eva (Licht 2012, 20. Gemeinschaftstagung der lichttechnischen Gesellschaften Deutschlands, der Niederlande, Österreichs und der Schweiz, 2012)

Untersuchung zur Einführung eines softwarebasierten technischen Risikomanagementsystems für Betreiber von Biogasanlagen (TeRiBi) – Zwischenergebnisse des Feldversuchs - Schneider, Michael; et al. (biogas – expo & congress (trinationaler Kongress), 2015)

Usable RTOS-APIs? - Klaus, Tobias; Franzmann, Florian Peter; Engelhard, Tobias; Scheler, Fabian; Schröder-Preikschat, Wolfgang (Proceedings of the 10th Annual Workshop on Operating Systems Platforms for Embedded Real-Time Applications, 2014)
UnivIS-Import:2015-04-16:Pub.2014.tech.IMMD.IMMD4.usable_0
Keywords: AORTA; RTSC

Using a Six-Port Device in an FM-CW Radar - Diskus, Christian; Stelzer, Andreas; Thim, Hartwig; Weigel, Robert (Proc. International Symposium on Microwave and optical Technology, 2001)
elib2cris::1512001600,diskus2001

Using Deep Learning to Demodulate Transmissions in Molecular Communication - Bartunik, Max; Keszöcze, Oliver; Schiller, Benjamin; Kirchner, Jens (2022 IEEE 16th International Symposium on Medical Information and Communication Technology (ISMICT), 2022)

Using Error-Source Switching (ESS) Concept to Analyze the Conducted Radio Frequency Electromagnetic Immunity of Microcontrollers - Su, Tao; Unger, Markus; Steinecke, Thomas; Weigel, Robert (IEEE Transactions on Electromagnetic Compatibility, 2011)
This paper introduces a new concept, the error-source switching (ESS), for the electromagnetic immunity of microcontrollers. Under the concept of ESS, a microcontroller is a multiple-module IC. A functional module, named as the error source (ES), is thebottleneck for the immunity of microcontrollers. During the sweeping of the disturbance frequency in the RF immunity test, the ES switches between various functional modules. Each functional module has an effective frequency range. Through the theoretical analysis, the measurement and the simulation, this paper shows that the frequency behavior of the conducted RF immunity of microcontrollers can be correctly understood and reasonably simulated when and only when the ESS mechanism is considered. That conclusion provides a criterion on how to construct microcontroller models and the simulation environment in a logical way for immunity simulations.
elib2cris::1512001600,su2011
Keywords: Electromagnetic compatibility (EMC); electromagnetic interference; failure analysis; integrated circuits (ICs); microcontrollers; simulation

Using Memristor Technology for Multi-value Registers in Signed-digit Arithmetic Circuits - Fey, Dietmar; Reichenbach, Marc; Söll, Christopher; Biglari, Mehrdad; Röber, Jürgen; Weigel, Robert (Proceedings of the Second International Symposium on Memory Systems, 2016)
Signed-digit (SD) arithmetic exploits positive and negative digits requiring more than two states. It is long known that an addition using trits, i.e. each digit stores not only a 0 or a 1 but also either 2 or -1, requires only a constant number of steps independent of the operands' word length. However, current processors could not profit from that due to the lack of fast, dense and CMOS compatible memory cells that can store reliably multiple states. Memristors offer these features making it necessary to re-evaluate different SD number representations and to evaluate the consequences of an implementation of a multi-value register file with memristors concerning latency, area and energy consumption. Using memristors as multi-value register reduces latency and area on one side compared to flip-flop based memories. On the other side this requires additional sophisticated control circuitry to implement ADCs/DACs, current limiting circuits and to generate control signals to read, write and erase memristors. The paper determines the break-even points at which ternary circuits attached to memristor based registers show better energy-delay products and less area consumption and how much power consumption these improvements cost. By layout synthesis is shown that ternary adders with trit-storing memristors can reduce the latency for a word length of 16 digits about 19% and about 52% for 512 digits compared to a binary carry-look-ahead (CLA) adder with nearly the same power consumption.
elib2cris::1512001600,fey2016a
Keywords: Signed-digit arithmetic multi-bit memristors memristive computing; multi-bit memristors; memristive computing; GRK

Using Metamaterial structures with frequency agile basestations - Dehm-Andone, Gunther; Adamiuk, Grzegorz; Fischer, Georg (German Microwave Conference (GeMiC 2006), 2006)
http://duepublico.uni-duisburg-essen.de/servlets/DerivateServlet/Derivate-14694/Final_Papers/GM0112-F.pdf
elib2cris::1512001600,dehm-andone2006

Utilizing the Ferromagnetic Battery of Capsule Endoscopes for Static Magnetic Localization - Zeising, Samuel; Ararat, Kivanc; Thalmayer, Angelika; Fischer, Georg; Kirchner, Jens (2021 IEEE 19th International Symposium on Antenna Technology and Applied Electromagnetics (ANTEM), 2021)

V2X in 3GPP Standardization: NR Sidelink in Release-16 and Beyond - Harounabadi, Mehdi; Mohammad Soleymani, Dariush; Bhadauria, Shubhangi; Leyh, Martin; Roth-Mandutz, Elke (2021)
The 5G mobile network brings several new features that can be applied to existing and new applications. High reliability, low latency, and high data rate are some of the features that fulfill the requirements of vehicular networks. Vehicular networks aim to provide safety for road users and several additional advantages such as enhanced traffic efficiency and in-vehicle infotainment services. This article summarizes the most important aspects of NR-V2X, which is standardized by 3GPP, focusing on sidelink communication. The main part of this work belongs to 3GPP Release 16, which is the first 3GPP release for NR-V2X, and the work/study items of the future Release 17.<br

Validation and Analysis of the Propagation Channel at 60 GHz for Vehicular Communication - Lübke, Maximilian; Fuchs, Jonas; Dubey, Anand; Hamoud, Hussein; Dressler, Falko; Weigel, Robert; Lurz, Fabian (2021 94th Vehicular Technology Conference, 2021)

Validation Data for WinProp and NYUSIM - Lübke, Maximilian; Dimce, Sigrid (2020)
This archive contains simulation data the same scenario that is used in the measurement campaign published in [1-3]. The directories correspond to the respective simulators that have been used. [1] M. Peter, R. Weiler, B. Goktepe, W. Keusgen, and K. Sakaguchi, "Channel measurement and modeling for 5G urban microcellular scenarios," MDPI Sensors, vol. 16, no. 8, p. 1330, 2016 [2] R. Weiler, M. Peter, W. Keusgen, A. Maltsev, I. Karls, A. Pudeyev, I. Bolotin, I. Siaud, and A.-M. Ulmer-Moll, "Quasi-deterministic millimeter-wave channel models in MiWEBA," EURASIP Journal on Wireless Communications and Networking, vol. 2016, Dec. 2016. [3] R. Weiler, M. Peter, W. Keusgen, and M. Wisotzki, "Measuring the busy urban 60 GHz outdoor access radio channel," in IEEE International Conference on Ultra-WideBand (ICUWB 2014), Paris, France, Sep. 2014

Validation of a Functional Principle for a Broadband Millimeter-Wave Power Detection Structure in a Recent BiCMOS Technology - Trenz, Florian; Weigel, Robert; Kissinger, Dietmar (IEEE Radio Frequency Integrated Circuits Symposium, 2017)
In this paper, a functional principle for a broadband thermal detector suited for a monolithical integration is shown. Two tantalum load resistors are heated by an input signal, while the temperature at a fixed distance is recorded on chip with a differential temperature sensing bridge. An integrated differential to single-ended stage amplifies the bridges differential voltage and makes an output voltage proportional to the input power of the detector available. The thermal resistance and capacitance between the load resistor and the sensing cell act as a low pass filter in the electrical regime. Based on this concept, a detector chip has been designed, which has been analyzed in thermal simulations. The realized detector has been characterized on-chip and bonded to a microwave substrate for a system performance estimation. Its input impedance is tuned to 50 Ohms and measured matching is better than -15dB from 10MHz to 43.5GHz. With a low supply voltage of 1.5V and its active area of around 80x36um2, the detector is suitable for an integrated power measurement solution.
Keywords: Detectors; Envelope detectors; Monolithic integrated circuits; BiCMOS integrated circuits; Thermodynamics

Validierung einer Messmethode zur Erfassung der magnetischen Schirmdaempfung eines Gehaeuses aus Drahtgeflecht und Vergleich mit einem analytischen Modell - Kuehn, M.; John, Werner; Weigel, Robert (Kleinheubacher Tagung, 2012)
elib2cris::1512001600,kuehn2012

Vampire Bats that Cooperate in the Lab Maintain Their Social Networks in the Wild - Ripperger, Simon; Carter, Gerald; Duda, Niklas; Kölpin, Alexander; Cassens, Björn; Josic, Darija; Berrío-Martínez, Jineth; Page, Rachel; Mayer, Frieder; Kapitza, Rüdiger (Current Biology, 2019)

VCO design in SiGe - Ußmüller, Thomas (Proceedings of the 1st Chinese-German Summer School (Embedded Systems and Materials - Research for Advanced Applications), 2006)
elib2cris::1512001600,ussmueller2006

Vehicle Self-Localization for Advanced Driver Assistance Systems - El Assaad, Ahmad; Krug, Markus; Fischer, Georg (WPNC’2016 IEEE 13th Workshop on Positioning, Navigation and Communications, 2016)
elib2cris::1512001600,assaad2016d

Velocity and Length Measurements using a 24-GHz Doppler-Radar - Kolmhofer, Erich; Pichler, Markus; Stelzer, Andreas; Weigel, Robert (Proc. International Conference on Sensors and Systems, 2002)
elib2cris::1512001600,kolmhofer2002

Velocity Estimation from Doppler Radar Measurements - Pichler, Markus; Stelzer, Andreas; Kolmhofer, Erich; Weigel, Robert (Proc. IEEE International Symposiumn on Theoretical Electrical Engineering, 2001)
elib2cris::1512001600,pichler2001a

Vergleich verschiedener schaltungskonzepte für stromgebende ladungspumpen in phasenregelschleifen - Jung, Melanie; Schmid, Konstantin; Fischer, Georg; Weigel, Robert; Ußmüller, Thomas (12. GMM/ITGFachtagung Analog, 2011)
elib2cris::1512001600,jung2011c

Vergleich von EMV-Simulation und EMV-Messungen in der KFZ-Technik - Scholl, Bernd; Englmaier, Armin; Weigel, Robert (Sechste Internationale Fachmesse und Kongress fuer Elektromagnetische Vertraeglichkeit, 1998)
elib2cris::1512001600,scholl1998

Verlustarme Oberflaechenwellenfilter fuer moderne Funkkommunikationssysteme im GHz-Bereich - Weigel, Robert; Anemogiannis, Kimon; Russer, Peter (Proc. Kleinheubacher Tagung, 1991)
elib2cris::1512001600,weigel1991

Verlustmechanismen in BAW-Komponenten für Mobilfunkanwendungen - Hagelauer, Amelie Marietta (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2013)

Vernetzte Umfeldsensorik mit adaptiven Radiointerferometern zur Distanzmessung mit Sechstortechnik : BMBF Verbundprojekt NetGuard6P : Gemeinsamer Abschlussbericht - Lenhard, Thilo; Wolz, Patrick; Kölpin, Alexander; Frank, Martin; Völkel, Matthias; Reißland, Torsten; Weigel, Robert; Ghesquiere, Pol; Lambrecht, Franziska; Kiefl, Stefan; Lasch, Markus; Sieber, Volker (2019)

Verschleißerkennung bei Kupferleitern - Baron, Philipp; Lenz, Philipp; Wittmann, Armin; Fischer, Georg (Draht, 2021)
Keywords: Kupfer; Rauheit; Verschleiß; Mechanische Kräfte

Vital Sign Sensors for Artificial Intelligence and Deep Learning - Kirchner, Jens; Fischer, Georg (52nd Annual Conference of the German Society for Biomedical Engineering, 2018)
Up to now vital data of patients are mostly acquired during clinical or ambulant examination. Here, the sensors are carefully placed by trained personal and movements of the patient are well controlled, e.g. during exercise ECG on a recumbent ergometer. In this way, misplacement of the sensors as well as motion artifacts are avoided, and physical load is well defined, such that high quality data is ensured that can be use for diagnostic purposes. Such a clinical or ambulant examination, however, captures only a short moment in time and is not representative for daily life. More preferable from the perspective of the treating physician would be data collected on a regular basis from daily routine work of the subjects. In such a situation, however, sensors may not be placed properly by the patient and movements are not well controlled any more, so data quality can be compromised. Hence, the validity of the sensor data has to be assessed and taken into account during data analysis in order to derive reasonable conclusions. Therefore, a wearable sensor system for daily life must be multimodal to allow machine learning algorithms to clean the acquired sensor data from artefacts. Artificial intelligence and deep learning system can then identify corrupt data segments, substract artefact patterns and by that clean up sensor data. The talk will highlight the trade-off between usability and integratability of a sensor system into daily life versus the validity of data obtained. This challenge will be illustrated by a multimodal sensor platform for elderly and dementia care that was developed during the course of the Medical Valley excellence cluster funded by German Federal Ministry of Education and Research (BMBF). Another example discussed in the talk are ECG circuit concepts that make the sensor more robust and compatible with daily life. Special focus will be put on capacitive ECG. Here, movement artefacts can be cleaned up if the movement during ECG aquisition is known, which can be done, e.g., by EMG or acceleration/gyroscopic sensors. Apart from that, these sensors allow to interpret the captured ECG data with respect to the current load to the body and thus provide context information. In conclusion, a combination of advancements in both sensor hardware/circuitry and multimodal sensor processing by artificial intellifence is needed to make the sketched vision real. <br
Keywords: Vital signs; artificial intelligence; deep learning

Vollwellenanalyse der Ausbreitung mikroakustischer Moden in Schichtstrukturen - Wallner, Paul; Schneider, Robert; Walliser, Beate; Holm, Andreas; Roesler, Ulrike; Ruile, Werner; Weigel, Robert (Kleinheubacher URSI/ITG-Tagung, 1996)
elib2cris::1512001600,wallner1996

Voltage and Current Selector Based Biasing Topology for Multiple Supply Voltage Circuits - Easwaran, Sri Navaneethakrishnan; Chellamuthu, Shanmuganad; Venugopal, Sunil Kashyap; Weigel, Robert (IEEE Transactions on Circuits and Systems II: Express Briefs, 2017)
In Systems on Chip (SOC) there are Multiple Supply Voltage designs where a module is powered by several supply rails. For example these rails are at 40V, 5V and 3.3V. A safe biasing scheme is needed to ensure no tri-stated biasing conditions can exist, which can result in unintended activation of the power stages or output drivers leading to high currents. It is shown here a safe biasing scheme can be implemented under any power sequencing scheme in Multiple Supply Voltage designs by exploiting the voltage and current selector topologies. This circuit was implemented in a 40V, 0.35μm, BiCMOS process on a 4 channel airbag squib driver IC. The fabricated circuit’s quiescent current is less than 5mA even if the on chip junction temperature is 175ºC and for various fault conditions that can occur in a multiple power supply domain.
elib2cris::1512001600,easwaran2017
Keywords: Rails; Logic gates; System-on-chip; Photonic band gap; Generators; State of charge; Digital audio players

Voltage clamping circuit with ±100 mV precision in high-voltage OTA - Easwaran, Sri Navaneethakrishnan; Venugopal, Sunil Kashyap; Weigel, Robert (Electronics Letters, 2016)
It is shown that precise output voltage clamping levels can be achieved under any operating condition by clamping the input of operational transconductance amplifier to a process insensitive reference and multiplexing the levels based on comparator decision. This circuit was implemented in a 40 V bipolar CMOS process. The fabricated circuit clamps the output voltage at 5.4 V with a precision of ±100 mV at 175°C on-chip junction temperature on the die. The input range for this circuit is between 100 mV and 25 V.
elib2cris::1512001600,easwaran2016b

Voltage controlled oscillator with frequency tripler in MHMIC technology for V-Band applications - Hofmann, Maximilian; Winkler, S.; Weigel, Robert; Wu, Ke; Kölpin, Alexander (German Microwave Conference, 2011)
A voltage controlled oscillator (VCO) for V-Band applications in miniaturized hybrid integrated circuit (MHMIC) technology is proposed. The introduced circuit is designed to provide its third harmonics in the unlicensed frequency band around 60 GHz. The underlying concept is based on a negative resistance oscillator (NRO), centered at 20 GHz and driven by a PHEMT Transistor. A 3 GHz tuning range is achieved by a voltage controlled load-network, which consists of a hybrid assembled varactor diode at the transistor drain electrode. The fundamental frequency is intended to drive a resistive frequency tripler. Two concepts, consisting of a single diode and a antiparallel diode multiplier are compared with -23 dB and -15.5 dB conversion gain, respectively.
elib2cris::1512001600,hofmann2011a

Vortrag zur Verbesserung der Norm DIN EN 50396 und Einreichung eines Normenverbesserungsvorschlages - Ehlenz, Tobias; Wittmann, Armin; Fischer, Georg (2018)

VV oder CC - wer hat die Nase vorn? - Es muss nicht immer der normale Opamp sein - Tietze, Ulrich; Ußmüller, Thomas (2005)
elib2cris::1512001600,tietze2005

Wafer Level Package Integrated Antenna Concepts for Circular Polarization - Schmidbauer, Philipp; Wojnowski, Maciej; Weigel, Robert; Hagelauer, Amelie Marietta (2018 IEEE 27th Conference on Electrical Performance of Electronic Packaging and Systems (EPEPS), 2018)
We prove design concepts for embedded wafer level ball grid array package integrated circularly polarized antennas in the 57 GHz to 64 GHz ISM band. Therefore, we propose performance requirements and evaluate the properties of four different antenna-in-package layouts based on electromagnetic full-wave simulations with focus on the axial ratio characteristic
Keywords: ball grid arrays; electromagnetic wave polarisation; millimetre wave antennas; wafer level packaging; antenna-in-package layouts; ISM band; electromagnetic full-wave simulations; axial ratio characteristics; circularly polarized antennas; embedded wafer level ball grid array package; design concepts; circular polarization; wafer level package integrated antenna concepts; frequency 57 GHz to 64 GHz; Patch antennas; Bandwidth; Polarization; Antenna feeds; Layout; antenna-in-package; mm-wave packaging; heterogeneous integration

Water Temperature Measurement by Microwave Six-Port Interferometry at 24 GHz - Talai, Armin; Mann, Sebastian; Weigel, Robert; Kölpin, Alexander (IEEE Topical Conference on Wireless Sensors and Sensor Networks (WiSNet), 2014)
Microwave interferometry enables the possibility of highly accurate distance measurements by evaluating phase differences. The reflected power is a function of the effective radar cross-section, the measurement distance, and the attenuation in air. An irradiated plain water surface shows a temperaturedependent behavior by means of the reflected power. This is due to the fact that the complex permittivity of water, as well as the refractive index, strongly depends on the water temperature within the 24 GHz Industrial, Scientific and Medical (ISM) band. Consequently, the effective radar cross-section depends on the temperature as well. This paper describes a method of monitoring the water temperature as a side effect of an interferometric radar in Six-Port technology for water level measurements.
elib2cris::1512001600,talai2014

Wave Propagation with HBC in a Human Arm Model - Ahmed, Doaa; Kirchner, Jens; Fischer, Georg (2017 IEEE International Symposium on Medical Measurements and Applications (MeMeA), 2017)
Today’s interest in health assistance systems, sport activities, person’s vital signs observing and remote patient monitoring require distributing various types of sensors at specific places across the human body. These sensors might be used to measure temperature, blood pressure level, blood glucose level and the like. This implies collecting the data generated at the distributed sensors in a wireless Body Area Network (BAN) and fusing these data at an access point (e.g. wristwatch) and then to a central processing unit (i.e., PC) for diagnosing, as shown in Fig. 1. However, sending data wirelessly is typically a very energy intensive task implying large batteries. Hence, BAN networks have been developed by IEEE 802.15.Task Group (TG6) to serve a variety of applications including medical, consumer lifestyle and the like at a low power consumption. Human Body Communications (HBC) is one technique used in BAN networks that utilizes the human body as a transmission medium to transfer data between sensors on, in or at the proximity of the human body using electrodes (i.e., electrical conductors).
Keywords: Body Area Communication; Galvanic Coupling; Human Arm Model

Wave Propagation with Human Body Communications in BANs - Ahmed, Doaa; Kirchner, Jens; Fischer, Georg (2017 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization for RF, Microwave, and Terahertz Applications (NEMO), 2017)
Today's interest in health assistance systems, sport activities and remote patient monitoring require distributing various types of sensors at specific places across the human body. These sensors might be used to measure temperature, blood pressure level, blood glucose level and the like. This implies collecting the data generated at the distributed sensors in a wireless Body Area Network (BAN) and fusing these data at a central processing unit, which transfers the data, if needed, to a hospital or medical center for diagnosing. Whereas, transmission could be done for real time or stored data depending on the application scenario. However, sending data wirelessly is typically a very energy intensive task implying large batteries. Hence, BAN networks have been developed by IEEE 802.15.Task Group (TG6) to serve a variety of applications including medical, consumer lifestyle and entertainment applications at low power consumption. Human Body Communication is a non-RF propagation system in BAN network that utilizes the human body as a transmission medium to transfer data between several points inside, on or sometimes near the human body using electrodes, rather than antennas based on near field communication and quasistatic field approximations.
Keywords: Body Area Communication; Galvanic Coupling; Human Arm Model

W-CDMA Terminal Transceiver RFICs - Maurer, Linus; Chabrak, Karim; Weigel, Robert (Proc. Asia-Pacific Microwave Conference, 2004)
elib2cris::1512001600,maurer2004a

Wearables with integrated Microwave-Sensors for Internet-of-Things-Applications (IoT) in the sector of health-care: An overview - Dietz, Marco; Guarin Aristizabal, Gustavo Adolfo; Hofmann, Maximilian; Nasr, Ismail; Nehring, Johannes; Lämmle, Benjamin; Schwarzmeier, Andre; Aufinger, Klaus; Hagelauer, Amelie Marietta; Fischer, Georg; Weigel, Robert; Kissinger, Dietmar (VDE Kongress 2016: Internet der Dinge, 2016)
elib2cris::1512001600,dietz2016a

Wearable System for Measurement of Thoracic Sounds with a Microphone Array - Kirchner, Jens; Souilem, Sara; Fischer, Georg (IEEE SENSORS 2017, 2017)
Acoustic signals from the thorax provide diagnostic information about the heart, the respiratory and the digestive system. This information is useful for both the detection of acute illness, e.g. in elderly care, and for the monitoring of chronic diseases. Here, a wearable system for long-term capture of thoracic sounds is proposed that comprises four microphones for physiological signals and one for noise from the surrounding. The performance of the prototype is evaluated in comparison to a reference stethoscope and under different wearing conditions. Combining the microphones will provide means for cancellation of environmental noise, fusion of acoustic signals from different physiological sources as well as focusing on a particular source by use of beamformin
Keywords: wearable system; long-term capture; microphones; physiological signals; acoustic signals; microphone array; diagnostic information; elderly care; wearing conditions; physiological sources; thoracic sounds measurement; chronic diseases monitoring; heart; microphones; prototypes; biomedical monitoring; stethoscope; acoustics; acoustic signals; wearable system; thorax; heart sounds; sensor array

Wear-Induced Attenuation on Transmission Lines and Their Causes - Lenz, Philipp; Baron, Philipp; Wittmann, Armin; Fischer, Georg (Transactions on Electrical and Electronic Materials, 2022)
In this paper, the radio frequency (RF) behavior of mechanically stressed coaxial and for the first time also twisted-pair transmission lines is investigated over their service life. The main goal is to enable predictive maintenance for cables in moving applications and avoid preventive replacement. This also reduces the use of high-cost resources. For this purpose, stranded and solid-core variants of coaxial and twisted-pair type cables are mechanically loaded on the two-pulley apparatus according to EN 50396. Their RF transmission (S21) behavior is measured using a vector network analyzer and presented over bending cycles. For the first time, the phase response of mechanically loaded transmission lines is evaluated with respect to their service life. Two significant causes for the increasing attenuation and altered phase response are identified: Breakage in foil screen and increasing surface roughness on the copper conductors. The identified causes are supported with literature evidence. Through measurements and theoretical calculations, it is proven that the phase is much more suitable for an assessment of the remaining service life than the amplitude. The findings can be used to implement a cable monitoring system in industrial environments which monitors the lines in-situ and reminds the user to replace them, whenever a certain wear-level is reache
Keywords: RF attenuation; Coaxial; twisted-pair; transmission phase; surface roughness; wear-level monitoring

Wear-Level-Monitoring on electrical conductors with high-frequency alternating currents - Lenz, Philipp; Wittmann, Armin; Fischer, Georg (Frequenz, 2020)
In this paper, a methodical approach for the in-situ monitoring of the mechanical wear of electrical conductors is presented. The state of life can be assessed by means of the characteristic attenuation of an applied high-frequency alternating current. The advantages of this appraoch include its non-destructive nature and the applicability to installed and otherwise inaccessible conductors.<br
Keywords: Cable Monitoring System; copper; skin effect; surface roughness

Weihnachtsbeleuchtung im Historischen Stadtkern: Glühlampe versus LED-Retrofit - Werner, Daniel; Schwenzfeier-Hellkamp, Eva (11. ETP Kongress Straßen¬beleuchtung 2012, 2012)

Well Design in a Bulk CMOS Technology with Low Mask Count - Jank, Michael; Kandziora, Christoph; Frey, Lothar; Ryssel, Heiner (AIP Conference Proceedings Volume 866, Issue 1, 2006)
Modifications in the implantation sequence offer wide potential for simplification in integrated circuit manufacturing. We present a novel concept for a CMOS process with only three front-end mask layers for fabrication of bulk CMOS devices. Process and device simulations demonstrate the manufacturability and scalability of the presented approach. © 2006 American Institute of Physics.
UnivIS-Import:2015-04-16:Pub.2006.tech.IE.LEB.wellde
Keywords: CMOS; High-energy ion implantation; Process simplification

White Paper on Machine Learning in 6G Wireless Communication Networks - Bhadauria, Shubhangi; et al. (2020)
This white paper discusses various topics, advances, and projections regarding machine learning (ML) in wireless communications. Sixth generation (6G) wireless communications networks will be the backbone of the digital transformation of societies by providing ubiquitous, reliable, and near-instant wireless connectivity for humans and machines. Recent advances in ML research have enabled a wide range of novel technologies such as self-driving vehicles and voice assistants. Such innovation is made possible by the availability of advanced ML models, large datasets, and high computational power. In addition, the ever-increasing demand for connectivity will require even more extensive innovation in 6G wireless networks. Consequently, ML tools will play a major role in solving the new problems in the wireless domain. In this paper, we offer a vision of how ML will impact wireless communications systems. We first provide an overview of the ML methods that have the highest potential to be used in wireless networks. We then discuss the problems that can be solved by using ML in various layers of the network such as the physical, medium-access, and application layers. Zero-touch optimization of wireless networks using ML is another interesting aspect discussed in this paper. Finally, at the end of each section, a set of important future research questions is presente

Wideband aeronautical channel sounding and modeling for C-band telemetry - Blümm, Christian; Heller, Christoph; Fourestie, Bertille; Weigel, Robert (24th International Symposium on Personal indoor and Mobile Radio Communications (PIMRC), 2013)
A new aircraft-to-ground telemetry link in C-band, based on Orthogonal Frequency Division Multiplexing (OFDM), is currently being developed for Airbus. In order to parameterize this link adequately, information about the propagation channel is indispensable, in particular in terms of delay spread and Doppler spread. In order to identify these characteristics, a novel easy-to-use channel sounder was developed and successfully applied in multiple flight campaigns. With the channel sounding results, three typical environments could be clearly distinguished according to their specific charateristics: Parking & taxiing, take-off & landing and en-route. The measurement results are directly applicable as constant coefficients for tapped-delay line modeling. In contrast, classical approaches apply coefficients of stochastical nature, modeled as random variables. However, for a specific communication scenario, which we face here, the proposed approach yields much more accuracy and reliability, as it represents the exact real-world channels.
elib2cris::1512001600,bluemm2013a
Keywords: Aircraft; Chirp; Delays; Doppler shift; OFDM; Telemetry

Wide-Band Nonlinear Chirp Transducers for Planar Acoustooptic Deflectors - Anemogiannis, Kimon; Russer, Peter; Weigel, Robert (IEEE MTT-S International Microwave Symposium Digest, 1989, 1989)
The design, fabrication, and performance characteristics of LiNbO/sub 3/-based wideband nonlinear interdigital chirp transducers are reported. A 54% bandwidth centered at 720 MHz has been obtained for a collinear deflector on a YX substrate. A 66% bandwidth at a midband frequency of 600 MHz has been designed for a Bragg deflector on a YZ substrate with electrodes tilted to satisfy the Bragg condition. Both transducers are down-chirp designs. The chirp waveform has been optimized using an accurate model of analysis. The transducers have been fabricated using 10:1 reduction projection printing and the liftoff technique. Good agreement has been found between theory and measurement. No severe bulk wave generation has been observed.<>
–empty–::1512001600,anemogiannis1989
Keywords: acousto-optical devices; integrated optics; lithium compounds; optical deflectors; ultrasonic transducers; 10:1 reduction projection printing; Frequency response; Surface acoustic waves

Wideband RF Interconnects for Organic Chip Packages - Comparison of single ended and differential transitions - Röhrl, Franz Xaver; Bogner, Werner; Jakob, Johannes; Hageneder, Daniel (European Microwave Conference (EuMC), 2015)
Embedding of semiconductor chips into organic substrates allows a cheap and high degree of miniaturization. For RF applications the connection between chip and package is as important as the connection between package and baseboard. This paper presents both single ended and differential transitions for RF packages with special reference to what should be considered when using organic printed circuit boards (PCBs). Because of the fully impedance controlled design process the presented transitions can be used from DC to 60 GHz and guarantee best signal integrity. In addition a fast and flexible measurement of the package - baseboard transition is shown by the use of a specific contact structure. Moreover it is figured out how the discontinuities of the interconnect structure of the chip package can be localized in detail using TDR measurements.

Wide-Range, Dual Six-Port based Direction-Of-Arrival Detector - Vinci, Gabor; Barbon, Francesco; Lämmle, Benjamin; Weigel, Robert; Kölpin, Alexander (German Microwave Conference (GeMiC) 2012, 2012)
Direction-Of-Arrival (DOA) detection is a challenge and a demanding task for several applications among industrial sensors and automotive radar where high accuracy, robustness, and low cost are important requirements. The six-port receiver based DOA detector has opened a whole new set of possibilities and implementations due to its accurate phase measurement properties. The DOA detection angle ambiguity issue of the six-port receiver caused by phase measurement periodicity is hereby adressed. A new high resolution dual six-port based detector is presented featuring among the advantages provided by the interferometric principle also an ambiguity-free wide detection range.
elib2cris::1512001600,vinci2012b
Keywords: Calibration; Detectors; Dynamic range; Phase measurement; Radio frequency; Receivers; Schottky diodes; Six-Port

Winkelschätzung mit linsenbasierten Radarsensoren für Kraftfahrzeuge - Mayer, Marcel (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2012)

Wireless Aircraft Cabin Communication - An ISM Band Cognitive Radio Approach - Blümm, Christian; Heller, Christoph; Weigel, Robert (8th Karlsruhe Workshop on Software radios, 2014)
elib2cris::1512001600,bluemm2014

Wireless Communication and Energy Harvesting for Implantable Sensor Devices - Walk, Jasmin (Radio Techniques and Technologies for Commercial Communication and Sensing Applications, RadioTecC, 2010)
elib2cris::1512001600,walk2010

Wireless Communication and Sensing Techniques Based on Surface Acoustic Wave Devices - Weigel, Robert; Reindl, Leonhard (Review of Radio Science: 1999-2002 URSI, 2002)
elib2cris::1512001600,weigel2002a

Wireless Communication and Sensing Techniques Based on Surface Acoustic Wave Devices - Weigel, Robert; Reindl, Leonhard (URSI, 2012)
elib2cris::1512001600,weigel2012a

Wireless Identification and Sensing Using Surface Acoustic Wave Devices - Springer, Andreas; Pohl, Alfred; Seifert, Franz; Weigel, Robert (The Sixth UK Mechatronics Forum International Conference, 1998)
elib2cris::1512001600,springer1998c

Wireless identification and sensing using surface acoustic wave devices - Springer, Andreas; Weigel, Robert; Pohl, Alfred; Seifert, Franz (Mechatronics, 1999)
Today Surface Acoustic Wave (SAW) devices are used in many electronic products, e.g. as filters in communications applications or for signal processing in radar systems. Due to the dependence of the propagation characteristic of the microacoustic wave on many physical parameters (e.g. temperature or strain) it is possible to build SAW sensors for a great variety of physical, chemical and biological parameters. SAW sensors are not only small, rugged and show small aging rates, they also can be used as wirelessly interrogable and completely passive sensors for many hostile environments. In this contribution the SAW device principles, design procedures and technological issues as well as examples of their use in certain measurement and identification applications are reviewed.
elib2cris::1512001600,springer1999

Wireless Identification and Sensing with Surface Acoustic Waves - Reindl, Leonhard; Weigel, Robert (Recent Research Developments in Microwaves Theory & Techniques, 1999)
This paper surveys the operating principles of surface acoustic wave(SAW)-based wireless identification and sensing and the state-of-the-art performance by way of a few examples which include the remote measurement of temperature, pressure, electrical current, and humidity.
elib2cris::1512001600,reindl1999

Wireless Infrared Communications with Edge Position Modulation for Mobile Devices - Lüftner, Thomas; Kröpl, Christian; Hagelauer, Richard; Huemer, Mario; Weigel, Robert; Hausner, Josef (IEEE Wireless Communications, 2003)
Driven by the Infrared Data Association, wireless infrared communication has become a very popular and widely used method for short-range data transmission between mobile devices like laptops, PDAs, and mobile phones. Especially in ad hoc connection applications, IrDA excels over radio-based solutions like Bluetooth or cable-based solutions like USB, due to the point-and-shoot characteristic of infrared communication. The quality and speed of infrared communications are mainly limited by the bandwidth of infrared transceivers. Therefore, it is important to use a modulation technique with high bandwidth efficiency, while simultaneously maintaining a low bit error rate and high power efficiency. Consequently, the IrDA has continuously improved the modulation techniques of its standards by introducing return to zero inverted (RZI) for the serial infrared (SIR) mode, 4-PPM for the fast infrared mode, and HHH(1,13) for the latest very fast infrared mode. This article presents a new modulation scheme called edge position modulation (EPM) with RLL coding, which offers increased bandwidth efficiency over the previous methods and attractive power efficiency. Since the novel modulation technique can be optimized to the characteristics of the wireless infrared channel, it also maintains low bit error rates.
elib2cris::1512001600,lueftner2003a
Keywords: infrared communication; IrDA; USB; Bluetooth; modulation techniques; HHH(1; 13); Edge Position Modulation; EPM; Run-Length-Limited Code; RLL(5; 12)

Wireless Infrared Communication System based on Edge Position Modulation - Lüftner, Thomas; Huemer, Mario; Kröpl, Christian; Hausner, Josef; Hagelauer, Richard; Weigel, Robert (Elektrotechnik und Informationstechnik, 2003)
Driven by the Infrared Data Association (IrDA) wireless infrared communication has become a very popular and widely used method for short range data transmission between mobile devices like laptops, PDAs and mobile phones. Quality and speed of infrared communications are mainly limited by the bandwidth of the infrared transceivers. Therefore it is important to use a modulation technique with a high bandwidth efficiency, while simultaneously maintaining a low bit error rate and high power efficiency. Consequently, IrDA has continuously improved the modulation techniques of its standards (IrDA, 2001) by introducing Return to Zero inverted (RZI), 4 Pulse Position Modulation (4-PPM) and HHH(1, 13), whereby the latest is basically a 2/3-rate Run-Length-Limited (RLL) code (Hirt, Hassner, Heise, 2001). Recently the authors have published a novel modulation scheme called Edge Position Modulation (EPM) with Run-Length-Limited (RLL) coding (Lueftner et al., 2003). This article will continue this work by presenting a completely new RLL(5, 12) code that is optimized for EPM.
elib2cris::1512001600,lueftner2003c
Keywords: Infrarotkommunikation; IrDA; USB; Bluetooth; Modulationsverfahren; RZI; Puls-Positions-Modulation; HHH(1; 13); Pulsflanken-Positions-Modulation; EPM; Lauflaengen limitierender Code; RLL(5; 12)

Wireless Infrared Communication System Based on Edge Position Modulation with a Novel 1/3-Rate RLL(5, 12) Code - Lüftner, Thomas; Huemer, Mario; Hausner, Josef; Hagelauer, Richard; Weigel, Robert (European Conference on Wireless Technology, 2003)
elib2cris::1512001600,lueftner2003

Wireless integrated sensor nodes for indoor monitoring and localization (invited) - Kissinger, Dietmar; Schwarzmeier, Andre; Grimminger, Florian; Mena-Carrillo, Juan; Weber, Werner; Hofer, Günter; Fischer, Georg; Weigel, Robert (IEEE Topical Conference on Wireless Sensors and Sensor Networks, 2015)
elib2cris::1512001600,kissinger2015

Wireless Power for Charging Health Assistance Watches - Schwarzmeier, Andre (IEEE European Microwave Week, 2013)
elib2cris::1512001600,schwarzmeier2013c

Wireless pressure and temperature measurement using a SAW hybrid sensor - Schimetta, Gernot; Dollinger, Franz; Scholl, Gerd; Weigel, Robert (IEEE Ultrasonics Symposium, 2000)
A passive pressure and temperature sensor unit based on the combination of a SAW reflective delay line with a high-Q capacitive pressure sensor is presented. Due to a symmetric arrangement of the impedance loaded splitfinger interdigital transducer (IDT) between two reference reflectors a temperature corrected evaluation of the pressure signal is enabled. A prototype of a tire pressure sensor unit is shown. In combination with a wheel arch antenna and a conventional transceiver unit a typical signal-to-noise rate of 20 dB resulting in a pressure accuracy of ±15 kPa was measured
elib2cris::1512001600,schimetta2000c
Keywords: Wireless sensor networks; Transducers; Tires; Temperature sensors; Temperature measurement; Surface acoustic waves; Prototypes; Impedance; Capacitive sensors; Delay lines

Wireless Production Tools - PMSE - Radio Spectrum Scanning at the Brazilian 2018 FIA Formula OneWorld Championchip - Fehr, Matthias; Minami, Mario; Filgueiras, Felipe; Seeger, Pia; Fontoura Ponchet, Andre; Fischer, Georg (SET International Journal of Broadcast Engineering, 2020)
Major international sporting competitions such as Formula 1 GP Championship offer a great opportunity to check the use of the frequency spectrum in many respects, such as operation, regulation, equipment, demands and conflicts between all involved professionals, content producers, technical support and local regulatory agencies. In this piece of work, spectral scanning recordings were performed in the range of 410 to 870 MHz, covering wireless PMSE microphones at the 2018 F1 GP Brazil. The spectral scanning equipment was installed at two different locations, the international technical area for the TV stations (compound) with the UFABC semi-portable 6 GHz R&S spectrum analyzer and the TV Globo booth with APWPT’s semi-portable 3 GHz R&S spectrum analyzer in the middle of the pit line. There was a distance of about 2 km between the two locations. The equipment, controlled by specialized software. The radio spectrum was in use both by the technical team and the TV content production teams themselves, as well as the production, transmission and communication content between the various teams and their car drivers and a crew in a helicopter equipped with video cameras. In the three official days of the event from November 9th Friday to 11th Sunday, during many practice laps of the Interlagos racetrack, the official classification laps and the F1 GP Race itself, many links of audio PMSE equipment were recorded, the essential data of which were continuously monitored. Finally, the spectrum recordings were compared with TV Globe's coordination information. This reduced errors in the evaluation of the spectrum recording. Using previous reports since 2014 we can compare the number of microphones used in the Brazilian F1 GP and contrast with analogous recording procedures in Italian F1 GP at the same period.<br
Keywords: PMSE; Spectrum Scan; Occupation receiver

Wireless Remote Identification and Sensing with SAW Devices - Reindl, Leonhard; Scholl, Gerd; Ostertag, Thomas; Pohl, Alfred; Weigel, Robert (IEEE 1998 MMT/AP International Workshop on Commercial Radio Sensor and Communication Techniques, 1998)
Surface acoustic wave (SAW) devices can be used as novel identification and sensor elements (transponders) that do not need any power supply and may be requested wirelessly. Such a transponder picks up an electromagnetic request signal and stores it until all echoes caused by multi-path propagation have died away. Then, a characteristic response signal is returned to the interrogator unit. Identification marks respond with their nonchanging identification pattern. In radio-link sensors, a physical or chemical quantity influences the propagation properties of the SAW and consequently changes the response pattern of the device. This paper surveys the operating principle of such sensors and their state-of-the-art performance. The discussion is illustrated by several examples such as temperature sensors and sensors for mechatronic applications.
elib2cris::1512001600,reindl1998

Wireless SAW-Sensors for Surface and Subsurface Sensing Applications Proc. of SPIE's 46th Annual Meeting - Stelzer, Andreas; Schimetta, Gernot; Reindl, Leonhard; Springer, Andreas; Weigel, Robert (International Conference on Subsurface Sensing Technologies and Applications III, 2001)
elib2cris::1512001600,stelzer2001c

Wireless SAW sensor techniques - Weigel, Robert; Reindl, Leonhard (Meeting on New High Performance Piezoelectric Single Crystals and Thin Films, and Applications for Next Generation Electronics and Communication Systems, 1998)
elib2cris::1512001600,weigel1998

Wireless Sensing and Communication - Weigel, Robert; Huemer, Mario; Stelzer, Andreas; Springer, Andreas (Proceedings of the 12th Internaitonal Conference SENSOR 2005, 2005)
elib2cris::1512001600,weigel2005b

Wireless sensing by means of passive multistandard RFID tags - Brenk, Daniel; Essel, Jochen; Heidrich, Jürgen; Weigel, Robert; Hofer, Günter; Holweg, Gerald (Sensors, 2009 IEEE, 2009)
This paper presents a generic sensor interface built in a 0.13 Ã Â¿m CMOS process capable of being applied in passive HF & UHF RFID Tags without any additional power supply. The sensor interface contains an ultra low-power successive approximation ADC that uses the capacitive charge redistribution technique for its integrated DAC. An on-chip temperature sensor and up to three additional sensor signals can be applied to the ADC. A conversion rate of 100 kSps is reached while consuming less than 1.5 Ã Â¿A at 0.9 Volt supply voltage.
elib2cris::1512001600,brenk2009c
Keywords: Humidity; Passive RFID tags; Radiofrequency identification; Wireless sensor networks

Wireless Sensor Platform for Detection of Vital Parameters of Bats - Duda, Niklas; Ripperger, Simon; Tschapka, Marco; Mayer, Frieder; Weigel, Robert; Kölpin, Alexander (International Engineering in Medicine and Biology Conference (EMBC), 2019)

Wireless technologies for grand challenges (guest editorial) - Kissinger, Dietmar (IEEE Microwave Magazine, 2014)
elib2cris::1512001600,kissinger2014

Wissenschaftliche Analyse der Wechselbiegeprüfung und multiphysikalische Untersuchung der Lebensdauer - Kabel für Industrie 4.0 - Ehlenz, Tobias; Wittmann, Armin; Fischer, Georg (2018)
Keywords: Kabel; Alterung

Wissenschaftliche Arbeitstechniken für die MINT-Fächer - Kirchner, Jens; Meyer, Sebastian (Springer Vieweg, 2022)
Das Buch vermittelt die grundlegenden Arbeitstechniken, die für Seminare und Abschlussarbeiten wie auch für die Erstellung wissenschaftlicher Publikationen im Bereich Mathematik, Informatik, der Ingenieur- und Naturwissenschaften (MINT-Fächer) nötig sind. Es deckt den gesamten Ablauf eines solchen wissenschaftlichen Projekts ab: angefangen von der Themendefinition und Projektplanung über die Grundlagen des wissenschaftlichen Arbeitens und Recherchierens bis zur Organisation und Aufbereitung von Informationen, strukturiertem Schreiben sowie Erstellen und Halten von Präsentatione
Keywords: Kommunikation im akademischen Umfeld; Vorarbeiten für Abschlussarbeiten; Abschlussarbeiten aus Projektmanagementperspektive; Einführung in LaTeX; Wissenschaftliche Methodik; Recherchieren und Referenzieren wissenschaftlicher Quellen; Aufbereiten von Informationen; Struktur und Stil; Publikationsprozess; Erstellen und Halten von Präsentationen

Wo ein Kabel ist, existiert auch ein Maschinenelement - Ehlenz, Tobias; Wittmann, Armin (Draht, 2015)
Keywords: Kabel

Workshop on RF Ssystes and Circuit Engineering for 3G Wireless Systems Like UMTS - Weigel, Robert; Springer, Andreas; Pretl, Harald; Thomann, Wolfgang (European Microwave Conference, 2001)
elib2cris::1512001600,weigel2001f

Workshop on RF Systems and Circuit Issues of Third Generation Wideband CDMA Systems Like UMTS - Weigel, Robert; Maurer, Linus; Adler, Bernd; Eichinger, Ludwig; Fenk, Josef; Thomann, Wolfgang; Pretl, Harald; Huang, Q. (IEEE International Microwave Symposium, 2001)
elib2cris::1512001600,weigel2001c

Workshop WS3: frequency agile and software defined radio - Weigel, Robert; Maurer, Linus; Fischer, Georg; Müller, Thomas; Scheele, Patrick (IEEE Radio and Wireless Conference, 2005)
Interest in reconfigurability with terminals, base stations and also whole wireless networks is significantly rising. Various research projects look at reconfigurability from an end to end perspective of a communication link. This implies that reconfigurability is reflected with the baseband signal processing part as well as with the RF part of a communication device. The workshop therefore addresses various aspects of reconfigurability with RF through offering frequency agility with the radio and with baseband processing through reconfigurable digital signal processing. Frequency agility is therefore understood as one aspect of a general view on software radio to realize multimode devices that are multistandard and multiband capable. A great challenge with reconfigurable devices is the optimization for the right balance between analog and digital signal processing and the way how imperfections of the hardware are compensated. The level of reconfigurability further depends on the tuneability of the used materials, the components and the architectural choices made. For cost efficient implementations of reconfigurable devices, integration techniques play a key role.
elib2cris::1512001600,weigel2005
Keywords: frequency; software defined radio

WR12 to planar transmission line transition on organic substrate - Jakob, Johannes; Sammer, Roman; Röhrl, Franz Xaver; Zorn, Stefan; Bogner, Werner (Proceedings of the European Microwave Conference 2019, 2019)
Transitions for planar transmission lines on printed circuit boards (PCB) to rectangular waveguide are challenging to design and manufacture. This paper introduces two transitions, the first one is a broadband transition from WR12 (60–90 GHz) waveguide to a stripline (SL) and the second is a narrowband transition to a grounded coplanar waveguide (GCPW). The focus at the first transition is based on the fact that signals can be transmitted in the complete EBand. In the process, many manufacturing possibilities were exploited. For the second transition, the focus was on manufacturability in order to achieve the most cost effective transition possible. Design, simulated and measured results will be presented.<br
Keywords: waveguide; PCB; transition; planar transmission line; grounded coplanar; stripline; WR12; GCPW

X-Parameter Characterization of SAW and BAW Components - a Review - Hagelauer, Amelie Marietta; Akstaller, Wolfgang; Musolff, Christian; Weigel, Robert (Seventh International Symposium on Acoustic Wave Devices for Future Mobile Communication Systems, 2018)
This paper surveys X-Parameter based characterization of surface acoustic wave (SAW) and bulk acoustic wave (BAW) components. Due to the increased integration of frontend modules in mobile devices, the power density in BAW and SAW components rises continuously. Furthermore, the demand for more frequency bands is required by advanced communication techniques. As a result, the probability of significant nonlinear emissions disturbing adjacent channels increases. Thus, the linearity of individual frontend components becomes more and more important. In order to comply with spectral emission masks and limitations on spurious emissions imposed by standards and specifications, accurate modeling of the device’s response is required. In this paper, two measurement setups which are based on a nonlinear vector network analyzer (NVNA) are utilized in order to characterize BAW and SAW filters. A high dynamic range is required because of the low power levels of the generated higher order harmonics. Two different measurement setup approaches are compared to each other. The application of frequency selective attenuators enables an increase of the dynamic range by more than 40 dB.

X-Parameter Characterization of TC SAW Filters with Enhanced Dynamic Range - Akstaller, Wolfgang; Musolff, Christian; Weigel, Robert; Hagelauer, Amelie Marietta (IEEE Transactions on Microwave Theory and Techniques, 2017)
Increasing the integration of radio frequency frontend modules for mobile communication devices results in rising power densities within the components. Additionally, advanced communication techniques demand for more frequency bands to be supported. As a result, the probability of significant nonlinear emissions disturbing adjacent channels increases, and accurate modeling of the device’s response is required. The X-parameter-based modeling approach can be applied to this problem. In this paper, a measurement setup, which is based on a nonlinear vector network analyzer, is utilized in order to characterize a surface acoustic wave (SAW) filter. Due to the low power levels of the generated higher order harmonics and the demand for a power sweep, a high dynamic range (DR) is required. The application of frequency selective attenuators enables an increase of the effective DR by more than 40 dB. Based on this improved measurement setup, single-tone and two-tone X-parameter models of the SAW filter are created and evaluated for their ability to predict intermodulation distortion (IMD). Classic, scalar IMD measurements are used as a reference for the assessment of capabilities and limitations of both X-parameter approaches.
Keywords: Attenuators; Frequency measurement; Harmonic analysis; Mathematical model; Power harmonic filters; Receivers; Surface acoustic waves; Intermodulation distortion (IMD); X-parameter; nonlinearity; surface acoustic wave (SAW) filter

YBCO Superconducting Microwave Components, Applied Superconductivity - Weigel, Robert; Valenzuela, Alejandro; Russer, Peter (World Congress on Superconductivity, 1993)
elib2cris::1512001600,weigel1993e

YBCO Superconducting Microwave Oscillator - Weigel, Robert; Valenzuela, Alejandro; Russer, Peter (Proc. of the Workshop on Microwave Devices with High Temperature Superconductors, 1992)
elib2cris::1512001600,weigel1992b

Yield Analysation and Optimization Methods for Active CMOS Pixels - Lindner, Claus; Söll, Christopher; Röber, Jürgen; Bänisch, Andreas; Weigel, Robert (8. GMM/ITG/GI-Fachtagung Zuverlässigkeit und Entwurf (ZuE), 2015)
This work explains how to simulate error sources in image sensors to analyze yield. Moreover, two circuitry-wise methods to reduce these interferences are proposed and their influences on yield and standard deviation caused by process variations and reset noise are analyzed. Thereby the biggest sources of interference within the pixel architectures are described. After comparing three different pixel architectures, their extracted layout is simulated and the results are compared. Especially the change of the yield and the standard deviation with and without the use of DS and CDS are analyzed. By applying the methods mentioned before the yield could be increased by up to 15.6 %.
elib2cris::1512001600,lindner2015b
Keywords: Yield Analysis; Active Cmos Pixel; Image Sensor; Correlated Double Sampling; Double Sampling; Simulation Method; GRK-1773

Zeitbereichsmodellierung von Streifenleitungselementen mit einer zweidimensionalen TLM-Methode - Bender, Harald; Isele, Bertram; Weigel, Robert; Hausner, Josef; Russer, Peter (Proc. Kleinheubacher Tagung, 1991)
elib2cris::1512001600,bender1991

Zeitdiskrete Delta-Sigma-Modulatoren mit GHz-Abtastung in CMOS - Oberst, Matthias (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2013)

Zero-Bias Schottky Power Detector Design for Six-Port based Radar Systems - Michler, Fabian; Lindner, Stefan; Lurz, Fabian; Erhardt, Stefan; Weigel, Robert; Kölpin, Alexander (European Microwave Conference, 2017)

A Grid-based Filter for Tracking Bats Applying Field Strength Measurements - Hartmann, Markus; Nowak, Thorsten; Pfadenhauer, Oliver; Thielecke, Jörn; Heuberger, Albert (12th Annual Conference on Wireless On-demand Network Systems and Services (WONS), 2016)
Nowadays, many applications demand precise localization information. One of those applications is wildlife monitoring, e.g. tracking of bats. Wireless sensor networks featuring field strength measurements are a promising approach to track tiny and lightweight animals. In this paper a robust grid-based filter for the localization of bats based on field strength measurements is proposed. Therefore, fundamentals of field strength-based direction finding and optimal filtering are presented. A gridbased filtering approach to the problem of field strength-based position estimation of bats is derived and evaluated by Monte Carlo simulations.
Keywords: Gain; Direction-of-arrival estimation; Antennas; Antenna measurements; Estimation; Trajectory; Bayes methods

Antenna pattern optimization for a RSSI-based Direction of Arrival (DoA) localization system - Hartmann, Markus; Pfadenhauer, Oliver; Patino-Studencki, Lucila; Tröger, Hans-Martin; Heuberger, Albert; Thielecke, Jörn (ION's Pacific PNT Conference, 2015)
UnivIS-Import:2015-04-17:Pub.2015.tech.IE.komele.antenn

Diplexing Distributed Power Amplifier for Mobile Applications - Wang, Wei (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2012)

Effiziente und robuste Funkübertragung von Messdaten in einem Magnetresonanztomographen - Wiehl, Michael (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2014)