A Novel ISAC Transmission Framework based on Spatially-Spread Orthogonal Time Frequency Space Modulation

Li S, Yuan W, Liu C, Wei Z, Yuan J, Bai B, Ng DWK (2022)


Publication Type: Journal article

Publication year: 2022

Journal

DOI: 10.1109/JSAC.2022.3155538

Abstract

In this paper, we propose a novel integrated sensing and communication (ISAC) transmission framework based on the spatially spread orthogonal time frequency space (SS-OTFS) modulation by considering the fact that communication channel strengths cannot be directly obtained from radar sensing. We first propose the concept of SS-OTFS modulation, where the key novelty is the angular domain discretization enabled by the spatial spreading/de-spreading. This discretization gives rise to simple and insightful effective models for both radar sensing and communication, which results in simplified designs for the related estimation and detection problems. In particular, we design simple beam tracking, angle estimation, and power allocation schemes for radar sensing, by utilizing the special structure of the effective radar sensing matrix. Meanwhile, we provide a detailed analysis on the pair-wise error probability (PEP) for communication, which unveils the key conditions for both precoding and power allocation designs for communication. Based on those conditions, we design a symbol-wise precoding scheme for communication based only on the delay, Doppler, and angle estimates from radar sensing, without the a priori knowledge of the communication channel fading coefficients, and also propose a suitable power allocation. Furthermore, we notice that radar sensing and communication requires different power allocations. Therefore, we discuss the performances of both the radar sensing and communication with different power allocations and show that the power allocation should be designed leaning towards radar sensing in practical scenarios. The effectiveness of the proposed ISAC transmission framework is verified by our numerical results, which also agree with our analysis and discussions.

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How to cite

APA:

Li, S., Yuan, W., Liu, C., Wei, Z., Yuan, J., Bai, B., & Ng, D.W.K. (2022). A Novel ISAC Transmission Framework based on Spatially-Spread Orthogonal Time Frequency Space Modulation. IEEE Journal on Selected Areas in Communications. https://dx.doi.org/10.1109/JSAC.2022.3155538

MLA:

Li, Shuangyang, et al. "A Novel ISAC Transmission Framework based on Spatially-Spread Orthogonal Time Frequency Space Modulation." IEEE Journal on Selected Areas in Communications (2022).

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