An improved scheme for large scale complex field network coding based on user clustering and relay selection strategy in wireless cooperative communication

Complex field network coding can earn larger diversity gain, better system reliability and higher network throughput in wireless communication with relay cooperative. An improved complex filed network coding scheme for large scale density network with user clustering and relay selection strategy will be proposed in this paper. The multiuser detector we employ is not based on maximum likelihood algorithm, but based on complex filed belief propagation algorithm improved from belief propagation decode algorithm of low density parity check code. As the same time, network decoding and channel decoding are combined together to form a joint network channel iterative decoder, in which the extrinsic information derive from network decode and that derive from channel decode can work well for each other. Numerical results are given to illustrate that our proposed scheme can provide better reliability, larger network diversity gain and higher throughput, more importantly, it can be well applied to large scale dense network when compared with traditional schemes.