Optimal sparse CDMA detection at high load

Jack Raymond

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arXiv · 0903.3715

Optimal sparse CDMA detection at high load

Jack Raymond

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Abstract

Balancing efficiency of bandwidth use and complexity of detection involves choosing a suitable load for a multi-access channel. In the case of synchronous CDMA, with random codes, it is possible to demonstrate the existence of a threshold in the load beyond which there is an apparent jump in computational complexity. At small load unit clause propagation can determine a jointly optimal detection of sources on a noiseless channel, but fails at high load. Analysis provides insight into the difference between the standard dense random codes and sparse codes, and the limitations of optimal detection in the sparse case.

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Jack Raymond. 2009-05-22. Optimal sparse CDMA detection at high load. https://arxiv.org/abs/0903.3715

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