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arXiv · 0906.2819

Disjoint LDPC Coding for Gaussian Broadcast Channels

Mahdi Ramezani·Masoud Ardakani
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Abstract

Low-density parity-check (LDPC) codes have been used for communication over a two-user Gaussian broadcast channel. It has been shown in the literature that the optimal decoding of such system requires joint decoding of both user messages at each user. Also, a joint code design procedure should be performed. We propose a method which uses a novel labeling strategy and is based on the idea behind the bit-interleaved coded modulation. This method does not require joint decoding and/or joint code optimization. Thus, it reduces the overall complexity of near-capacity coding in broadcast channels. For different rate pairs on the boundary of the capacity region, pairs of LDPC codes are designed to demonstrate the success of this technique.

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Mahdi Ramezani, Masoud Ardakani. 2009-06-15. Disjoint LDPC Coding for Gaussian Broadcast Channels. https://doi.org/10.1109/isit.2009.5205588

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