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arXiv · 0910.1145

Design of network-coding based multi-edge type LDPC codes for multi-source relaying systems

Jun Li·Marwan H. Azmi·Robert. Malaney·Jinhong Yuan
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Abstract

In this paper we investigate a multi-source LDPC scheme for a Gaussian relay system, where M sources communicate with the destination under the help of a single relay (M-1-1 system). Since various distributed LDPC schemes in the cooperative single-source system, e.g. bilayer LDPC and bilayer multi-edge type LDPC (BMET-LDPC), have been designed to approach the Shannon limit, these schemes can be applied to the $M-1-1$ system by the relay serving each source in a round-robin fashion. However, such a direct application is not optimal due to the lack of potential joint processing gain. In this paper, we propose a network coded multi-edge type LDPC (NCMET-LDPC) scheme for the multi-source scenario. Through an EXIT analysis, we conclude that the NCMET-LDPC scheme achieves higher extrinsic mutual information, relative to a separate application of BMET-LDPC to each source. Our new NCMET-LDPC scheme thus achieves a higher threshold relative to existing schemes.

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Jun Li, Marwan H. Azmi, Robert. Malaney, Jinhong Yuan. 2009-10-07. Design of network-coding based multi-edge type LDPC codes for multi-source relaying systems. https://arxiv.org/abs/0910.1145

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