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arXiv · 2607.17755

On the Detection Optimality and Exact BER Analysis of NOMA

Tasneem Assaf·Hamad Yahya·Arafat Al-Dweik
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Abstract

Non-orthogonal multiple access (NOMA) detection using successive interference cancellation (SIC) and joint multiuser maximum likelihood (JML) has been extensively studied, although their presumed optimality for individual-user bit error rate (BER) minimization is unestablished. Moreover, existing BER analyses overlook the SIC-induced statistical changes. This letter derives optimal per-user maximum a posteriori (MAP) detectors, identifies when the near-user detector reduces to conventional SIC, and proves the equivalence of conventional SIC and JML. An exact average BER analysis accounting for SIC-induced statistical changes is presented. The results show that the proposed detector achieves modest but consistent BER gains at low-to-moderate signal-to-noise ratio (SNR).

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BibTeXRIS

Tasneem Assaf, Hamad Yahya, Arafat Al-Dweik. 2026-07-20. On the Detection Optimality and Exact BER Analysis of NOMA. https://arxiv.org/abs/2607.17755

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