中文摘要：

对多入多出多中继系统中的单播中继协议进行了性能分析,给出了接收信噪比表达式,该表达式可表示为中继节点前向/反向信道部分奇异值和部分奇异矢量夹角的函数.基于容量最大化准则,简化了单播中继协议的容量表达式,提出了基于瞬时信道状态信息和平均信道状态信息的中继节点选择方法,实现了信道信息反馈开销与系统各态历经容量之间的折中.

英文摘要：

The unicasting relay protocols in multi-input-multi-output multi-relay systems are analyzed. The expression of the received signal-to-noise ratio with unicasting relay protocols is derived,which is a function of some singular values and angles between singular vectors related to backward and forward channels. Based on the maximizing capacity criterion,the relay selection strategies with instantaneous and average channel state information are presented with simplifying the capacity expression. With average channel state information it is a trade-off scheme between the feedback overhead and the ergodic capacity performance.