Müller R (2021)
Publication Type: Journal article
Publication year: 2021
Book Volume: 23
Article Number: 539
Journal Issue: 5
DOI: 10.3390/e23050539
In 2017, Polyanskiy showed that the trade-off between power and bandwidth efficiency for massive Gaussian random access is governed by two fundamentally different regimes: low power and high power. For both regimes, tight performance bounds were found by Zadik et al., in 2019. This work utilizes recent results on the exact block error probability of Gaussian random codes in additive white Gaussian noise to propose practical methods based on iterative soft decoding to closely approach these bounds. In the low power regime, this work finds that orthogonal random codes can be applied directly. In the high power regime, a more sophisticated effort is needed. This work shows that power-profile optimization by means of linear programming, as pioneered by Caire et al. in 2001, is a promising strategy to apply. The proposed combination of orthogonal random coding and iterative soft decoding even outperforms the existence bounds of Zadik et al. in the low power regime and is very close to the non-existence bounds for message lengths around 100 and above. Finally, the approach of power optimization by linear programming proposed for the high power regime is found to benefit from power imbalances due to fading which makes it even more attractive for typical mobile radio channels.
APA:
Müller, R. (2021). Soft interference cancellation for random coding in massive gaussian multiple-access†. Entropy, 23(5). https://dx.doi.org/10.3390/e23050539
MLA:
Müller, Ralf. "Soft interference cancellation for random coding in massive gaussian multiple-access†." Entropy 23.5 (2021).
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