中文摘要：

针对正交频分多址接入（OFDMA）系统的子载波分配问题，提出了一种基于预期容量损失的分配算法，该算法将子载波的联合分配分解为逐次分配以降低复杂度。每次分配时，该算法利用多用户频率选择性信道的特性，将用户在不同子载波上的速率差值作为每次分配中预期容量损失的度量，优先对预期容量损失最大的用户分配子载波，以期避免由逐次分配的非最优性导致的系统容量损失。理论分析和仿真结果表明，此算法能够在低复杂度的条件下得到近似最优解，在保证用户服务质量的同时，有效地提高了系统容量。

英文摘要：

An estimated difference value based subcarrier allocation algorithm is proposed for orthogonal frequency division multiple access （OFDMA） networks to minimize the capacity loss. The joint subcarrier allocation procedure is divided into muhi-step allocation to reduce the complexity. By utilizing the characteristic of multiuser frequency selective channel and considering the impact on the next step＇s allocation, the algorithm allocates subcarriers to the users with high estimated capacity loss. The analysis and simulation results demonstrate that the proposed algorithm can achieve near optimal solution with lower complexity compared with the optimal Hungarian algorithm. It can well balance performance and complexity and effectively improve system capacity.