非理想信道信息下双向多中继选择系统性能分析

该文在双向多中继选择系统中，分析了采用自适应调制的基于三时隙时分广播(TDBC)中继传输协议的系统性能，给出了存在信道估计误差时，系统的端到端信干噪比表达式，然后通过不等式缩放将表达式转化为多个服从指数分布变量和的形式，求出了其上界的分布，并利用该分布推导出了系统平均频谱效率的上界闭式表达式。通过仿真可以看出，理论分析结果与蒙特卡洛仿真结果相吻合，随着信道估计误差的增加，系统的平均频谱效率降低，并会由于自干扰不能完全被消除而出现平台。为了降低信道估计误差对系统性能的影响，该文进一步提出了一种中继端最优的功率分配策略。

Performance Analysis of Two-way Multiple Relay Selection Systems under Imperfect CSI

Performance is analyzed of the multiple two-way relaying systems with three-slot Time Division BroadCast (TDBC) protocol employing adaptive modulation. The end-to-end SINR of the system is presented when channel estimation error exists. Then the distribution of its upper bound is given by transforming the expression to sum of multiple variables which obey exponential distribution through inequality zooming. Upper bound of the close-form expression of average spectrum efficiency is derived employing the distribution. Simulations show that the theoretical analysis matches well with the Monte Carlo results. The average spectrum efficiency decreases when the channel estimation error increases. Error floor will emerge for the self-interference can not be totally eliminated. Whats more, the optimal power allocation strategy at relay to reduce the impact of channel estimation error is proposed.