混合衰落信道下选择中继译码转发的性能分析

 蜂窝中继通信中基站到中继以及中继到移动台可以建模成混合衰落信道，即基站到中继的信道通常经历莱斯衰落，中继到移动台的信道通常经历瑞利衰落。该文研究混合衰落信道下协同通信系统中两跳译码转发方式的性能，首先通过分析推导了基于选择最佳中继的中断概率、误符号率以及误符号率的渐近线的闭式表达式，然后基于误符号率的渐近线给出了一种功率优化方法。蒙特卡洛仿真验证了理论公式，仿真结果显示优化功率分配的性能优于平均功率分配的性能。

Performance Analysis of Decode-and-forward Transmission with Relay Selection in Mixed Fading Channels

The channels between the Base Station and the relays (BS-relay) and those between the relays and the MoBile stations (relay-MB) can be modeled as mixed fading channels in cellular communication relay, which means that the BS-relay channels are Rician fading channels and the relay-MB channels are Rayleigh fading channels. The performance of a dual-hop decode-and-forward relay system is investigated in the mixed fading channels. Firstly, under optimal relay selection, the closed-form expressions for the outage probability, average symbol error probability and asymptotic average symbol error probability are derived. Secondly, an optimizing power allocation method is derived based on the asymptotic average symbol error probability. Monte Carlo simulations validate the analysis and the simulation results show that the system performance under optimal power allocation is better that under equal power allocation.