OFDM系统中的自适应比特功率分配算法

Adaptive bit and power allocation algorithm for OFDM system

摘要:

正交频分复用(OFDM)系统各子信道具有不同的衰落特性，如果采用相同的调制方式，则不能更好地利用系统资源。在系统容量受限和误比特率一定的条件下，文章提出了一种高效的OFDM自适应比特功率分配算法。在要求误比特率BER<10-3时，该算法与Chow算法相比，发射总功率减小了2.5 dB；与Hughes-Hartogs算法相比，系统消耗的总时间也明显缩短。仿真结果验证了算法的有效性。

Abstract:

Each channel of Orthogonal Frequency Division Multiplexing(OFDM) system has its own fading characteristic. The system resources will not be made the best of if the same modulation mode is adopted. This paper proposes an efficient bit and power allocation algorithm for single user OFDM system under limited system capacity and a certain Bit Error Rate(BER). When the required BER is below 10-3，the proposed algorithm reduces the sending power by almost 2.5 dB compared with Chow algorithm. It also significantly reduces the time consuming under the constraint of system capacity. The simulation results show the effectiveness of this algorithm.