基于混合译码放大转发的最优中继选择方案

Optimal Relay Selection Scheme Based on Hybrid Decode-Amplify-and-Forward

为在较低误码率的基础上延长网络寿命,提出基于混合译码放大转发(AF)中继策略的最优中继选择方案。通过构造基于目的节点接收信噪比和网络寿命中继选择的联合优化函数,实现最优中继的选择。设定中继节点的接收信噪比门限,根据信噪比门限值,将所有的中继节点分为AF和译码转发2种中继策略转发类型,分别计算2种类型的中继节点在目的节点的接收信噪比,根据中继选择的联合优化函数合理选择最优中继。仿真结果表明,在相同条件下,与基于AF的中继选择方案相比,该方案不仅在误码率性能方面有明显改善,而且可以延长网络寿命,提升系统性能。

In order to extend the network life on the base of lower Symbol Error Rate（ SER）,a relay selection scheme based on Hybrid Decode-Amplify-and-Forward（ HDAF） relaying method is proposed. Joint optimization function about receiving Signal to Noise Ratio（ SNR） at the destination and network life is defined to select the optimal relay. For the given threshold SNR at the relay nodes,all relay nodes are divided into two types： forwarding signal by Amplify-andForward（ AF） relaying method and forwarding signal by Decode-and-Forward（ DF） relaying method. The receiving SNR at the destination for each relay node is calculated and the optimal relay is selected reasonably according to the joint optimization function. Simulation results show that under the same conditions,the proposed relay selection scheme,compared with the relay selection scheme based on AF relaying method,not only achieves much better performance in SER,but extends the network life,improves system performance.