针对多用户协作中继系统中的功率最小化问题,提出了一种基于联合子载波配对及分配的资源分配算法.首先根据不同用户的目标速率要求及平均信道增益进行子载波数目的分配;然后以信道条件最佳为准则,提出了一种联合子载波配对及分配的多用户迭代算法,以实现对每个用户的中继链路和直传链路分别进行子载波配对及虚拟配对;最后利用注水算法对子载波进行功率分配,从而保证各用户以最小功率进行传输.仿真结果表明,该算法在满足用户目标速率的情况下,能够进行有效的子载波配对及分配,从而最小化系统的发射功率.
For the power minimization problem in multi-user cooperative relay communications,a resource allocation algorithm based on joint subcarrier pairing and assignment was proposed.Firstly,according to the average channel gain and the target rates of user,the assignment of subcarrier numbers was addressed.Then,in order to choose the subcarrier with best channel condition,a multi-user iterative algorithm for joint subcarrier pairing and assignment was proposed,which could achieve the subcarrier pairing in the cooperative transmissions and virtual pairing in the direct transmission,respectively.Finally,the power allocation was conducted by the water-filling algorithm,so that each user could use the minimum power for transmission.The simulation results indicate that the proposed algorithm can conduct subcarrier pairing and assignment effectively to minimize the total transmission power while meeting the users' target rate requirement.