This paper studies a resource allocation problem for heterogeneous services in amplify-and-forward OFDM relay system under separate power constraints. A resource allocation scheme is proposed to maximize the data rate of non-realtime service (NRTS) users while satisfying the requirement of realtime service (RTS) users. The problem is decomposed into two sub-problems: resource allocation for RTS and NRTS. The problem of RTS is solved with the Lagrangian method, while for NRTS, each subcarrier is allocated to the user with the best channel gain, and a two-step method is proposed for power allocation. First, the initial power allocation is done under the total power constraint. The subcarrier power is adjusted to satisfy the separate power constraints. A low complexity algorithm is proposed for subcarrier set allocation. Simulation results show that the proposed scheme optimizes the system performance with low complexity while satisfying the requirements of heterogeneous services users.%针对独立功率限制、放大一转发OFDMA中继系统的多业务资源分配问题,提出一种在满足实时用户要求前提下,非实时用户数据速率最大化的资源分配方案.根据业务的不同将问题分解为实时和非实时用户的资源分配两个子问题.对于实时用户的资源分配,利用Lagrange方法计算.对于非实时用户的资源分配,每个子载波分配给信道条件最好的用户,针对功率分配提出两步功率分配方法.首先按照总功率约束进行初始功率分配,然后对各子载波的功率进行调整以满足独立功率约束.对于子载波分配提出一种低复杂度的子载波集合分配算法.仿真结果表明,该方案在满足多业务用户要求的同时使系统性能得到优化,且计算复杂度低.
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