中文摘要：

在双向多中继OFDM网络中，提出了一种高信噪比下的功率分配与子载波配对的联合算法，与传统的基于中继选择的算法不同，允许所有中继转发同一子载波对，从而提高系统的额外分集增益。该算法在系统总功率受限的条件下，首先应用柯西不等式优化分配了所有中继总功率为定值时各个中继的最优功率，简化原有的最优系统模型；再应用二分法，通过最大化不同子载波对下的等效信道增益计算出源节点与中继节点的功率分配；最后通过凸规划分配不同子载波对的功率，并应用匈牙利算法进行子载波配对，获得最大的系统容量。由于双向多中继网络中功率分配算法过于复杂，目前尚没有计算复杂度较低的最优功率分配方式，该算法大大降低了功率分配的复杂度，并通过仿真结果表明其性能优于最优单中继选择算法和基于中继选择的功率分配算法。

英文摘要：

A joint optimization scheme for power allocation and subcarrier pairing under high SNR in two-way multi-relay OFDM system was proposed.Unlike those schemes in which relays use subcarriers separately,all the relays were allowed to forward signal on each subcarrier pair for providing much space diversity.With the constraint of total system power,the proposed scheme firstly allocated each relay power with Cauchy inequality with the assuming that the total relay power was fixed.Then the dichotomy was used to calculate the power allocation between the source node and the relay node by maximizing the equivalent channel gain for different subcarrier pairs.Lastly,the power of different subcarrier pairs was allocated by convex programming,and the subcarriers were paired by Hungarian algorithm to obtain the maximum system capacity.There was no optimal power allocation method with low complexity because of the complexity of the power allocation algorithm in two-way multi-relay networks.This algorithm greatly reduces the complexity of power allocation and simulation results show that the proposed scheme outperforms the relay selection scheme and the relays use subcarriers separately scheme.