【摘要】 针对单中继与等功率全中继策略在Nakagami-m衰落信道中通信中断率较高的问题,提出了在m为任意值的Nakagami-m衰落信道中能够明显降低通信中断率的基于放大转发协议的机会中继策略.该中继策略的最优中继选择过程无需知道全部的信道信息,仅依据源与目的地发出的标志信息来实现,从而简化了系统设计.所提策略以降低通信中断率为目标,采用近似理想功率分配原则进行信息传输,能适用较普遍的信道条件,其通信中断率的精确值还可通过计算得到,因此它不仅能改善系统的性能,还具备较好的实用性.理论分析及仿真结果表明,在Nakagami-m衰落信道中,当衰落系数m为4,通信中断率为10-2时,与等功率全中继和单中继策略相比,机会中继策略能获得约9 dB的信噪比增益.更多还原

【Abstract】 Focusing on the high outage probability of single relay and multiple-relay with equal power allocation strategies in Nakagami-m fading channels,an opportunistic relaying strategy with amplify-and-forward that decreases the outage probability in Nakagami-m fading channels is proposed.The optimal relay selection process in the proposed relaying strategy does not require all the channel state information but the transmission flag signals of source and destination,and hence,the system design is simplified.The proposed strategy is introduced to minimize the outage probability,and applies the near optimal power allocation method to transmit signals.It could be used in more generalized channels and it’s exact outage probability can be obtained by calculating.The proposed strategy not only improves the system performance,but also has the practicability.Theoretical analysis and comparisons with the single relay and the multiple-relay with equal power allocation strategies show that when the fading parameter m=4 and outage probability is 10-2,the signal-to-noise ratio of the opportunistic relay strategy could gain about 9 dB in Nakagami-m fading channels.更多还原