无线多中继系统中判决门限辅助的快速Z转发协作

针对Z向转发(ZF)协作所有中继节点均参与协作转发导致的能耗利用不合理问题, 该文提出了一种适用于多中继场景下的门限辅助判决快速Z转发(DT-FZF)协作.当中继节点处接收信号对数似然比(LLR)的绝对值小于门限时,中继节点不参与协作转发;否则中继节点协作转发经截断后的对数似然比(LLR).放大转发(AF)、译码转发(DF)、分段转发(PF)和ZF协作可看作DT-FZF协作的特殊情况.在三中继系统,误比特率(BER)为10–3时,相比ZF协作,所提协作可获得约0.8 dB的性能增益.

Decision Threshold-aided Fast Z-Forward in Wireless Multirelay Communications

In consideration of improper power allocation and insufficient relay selection in the current Z-Forward (ZF) scheme, an efficient Decision Threshold-aided Fast Z-Forward (DT-FZF) scheme is proposed to improve power and transmission efficiency. When the absolute value of the Log-Likelihood Ratio (LLR) of a source-relay reception is less than the decision threshold, the relay remains quiet. Otherwise, it directly sends the truncated LLR to the destination. In addition, the proposed DT-FZF scheme incorporates the Amplify-Forward(AF), Decode-Forward(DF), Piecewise-Forward(PF) and ZF schemes, all of which can be the special case of the proposed scheme. At a Bit Error Rate (BER) is of 10–3, the DT-FZF scheme outperforms the ZF scheme by approximately 0.8 dB in a three-relay system.