多协作中继系统的最优功率分配

Optimal Power Allocation for Cooperative Communication with Multiple Relays

为研究中继系统的功率分配对系统容量的影响,探讨总功率一定的情况下,为达到系统容量最大的中继系统的最优功率分配.提出了协作通信中多协作中继和多接收天线功率分配的分析模型.采用了矩阵的奇异值分解(SVD)的方法来分析系统的信道矩阵,得到了一种在功率一定的条件下使信道容量达到最大的最优功率分配方案(OPA),得出了最优功率分配系数的封闭表达式,并在相同假设条件下与平均功率分配(EPA)进行比较,得出在相同条件下OPA比EPA的性能好.

An analytical model for power allocation based on multiple cooperative relays and multiple antennas at the destination in cooperative communication is presented. An optimal power allocation scheme （OPA）, through singular value decomposition （SVD） of the channel matrix, is developed among the relay nodes under a certain power constraint to achieve the maximum channel capacity. Using Lagrange multiplier the expression of the optimal power allocation coefficient is derived. Compared with the equal power allocation （EPA） scheme, the OPA can obtain higher capacity gain and outage probability gain.