一种利用软信息网络编码在双向中继网络进行估计转发的方法

 在本文中,我们为双向中继网络(Two-way Relay Networks)设计了一种崭新的估计-转发(EF:Estimate-and-Forward)方法.在中继端信道解码后首先得到每一比特的对数似然比(LLR:Log-Likelihood Ratio),然后利用两个方向的比特LLR进行软信息网络编码,并借此构造出中继端的发送信号.因为此方法保留了两端比特信息的软信息并抑制了噪声,所以在任何条件下它的性能都要优于传统的放大-转发(AF:Amplify-and-Forward)方式和解码-转发(DF:Decode-and-Forward)方式,文中详细推导了三种转发方式的最大可达速率,得到EF方式下最大可达速率的上界和下界,还证明了EF方式较其它两种方式节省功率消耗,并通过仿真得到了速率曲线与误码率曲线,明确的验证了EF的优势.

An Estimate-and-Forward Scheme for Two-way Relay Networks with Soft Network Coding

This paper proposes a simple estimate-and-forward(EF) scheme for two-way relay networks.The relay node firstly calculates log-likelihood ratio(LLR) of bits from source nodes,then physical network encoding is performed in LLR domain instead of binary bits.The resulting new LLR is employed to generate the transmitted symbols at relay.Both upper and lower bounds are derived on the achievable sum rate of the proposed EF scheme.Performance evaluations confirm that EF scheme can improve the achievable sum rate and the bit error rate compared to conventional amplify-and-forward(AF) and decode-and-forward(DF) schemes.