Worst-Case Per-User Error Bound for Asynchronous Unsourced Multiple Access
CoRR(2024)
摘要
This work considers an asynchronous _a-active-user unsourced
multiple access channel (AUMAC) with the worst-case asynchronicity. The
transmitted messages must be decoded within n channel uses, while some
codewords are not completely received due to asynchronicities. We consider a
constraint of the largest allowed delay of the transmission. The AUMAC lacks
the permutation-invariant property of the synchronous UMAC since different
permutations of the same codewords with a fixed asynchronicity are
distinguishable. Hence, the analyses require calculating all
2^_a-1 combinations of erroneously decoded messages. Moreover,
transmitters cannot adapt the corresponding codebooks according to
asynchronicity due to a lack of information on asynchronicities. To overcome
this challenge, a uniform bound of the per-user probability of error (PUPE) is
derived by investigating the worst-case of the asynchronous patterns with the
delay constraint. Numerical results show the trade-off between the
energy-per-bit and the number of active users for different delay constraints.
In addition, although the asynchronous transmission reduces interference, the
required energy-per-bit increases as the receiver decodes with incompletely
received codewords, compared to the synchronous case.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要