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arXiv · 1102.3061

Improvement of BP-Based CDMA Multiuser Detection by Spatial Coupling

Keigo Takeuchi·Toshiyuki Tanaka·Tsutomu Kawabata
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Abstract

Kudekar et al. proved that the belief-propagation (BP) threshold for low-density parity-check codes can be boosted up to the maximum-a-posteriori (MAP) threshold by spatial coupling. In this paper, spatial coupling is applied to randomly-spread code-division multiple-access (CDMA) systems in order to improve the performance of BP-based multiuser detection (MUD). Spatially-coupled CDMA systems can be regarded as multi-code CDMA systems with two transmission phases. The large-system analysis shows that spatial coupling can improve the BP performance, while there is a gap between the BP performance and the individually-optimal (IO) performance.

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Keigo Takeuchi, Toshiyuki Tanaka, Tsutomu Kawabata. 2011-04-20. Improvement of BP-Based CDMA Multiuser Detection by Spatial Coupling. https://arxiv.org/abs/1102.3061

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