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arXiv · 2312.16781

Study of Adaptive LLR-based AP selection for Grant-Free Random Access in Cell-Free Networks

R. Di Renna·R. C. de Lamare
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Abstract

This paper presents an iterative detection and decoding scheme along with an adaptive strategy to improve the selection of access points (APs) in a grant-free uplink cell-free scenario. With the requirement for the APs to have low-computational power in mind, we introduce a low-complexity scheme for local activity and data detection. At the central processing unit (CPU) level, we propose an adaptive technique based on local log-likelihood ratios (LLRs) to select the list of APs that should be considered for each device. Simulation results show that the proposed LLRs-based APs selection scheme outperforms the existing techniques in the literature in terms of bit error rate (BER) while requiring comparable fronthaul load.

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R. Di Renna, R. C. de Lamare. 2023-12-28. Study of Adaptive LLR-based AP selection for Grant-Free Random Access in Cell-Free Networks. https://arxiv.org/abs/2312.16781

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