FFT在码分多址通信中的应用研究

A Study on Application of FFT to CDMA Communication

扩频序列的设计和选择是码分多址(CDMA)扩频通信的关键技术。同时,随着扩频序列长度的增加,序列相关函数的计算量迅速增加,常规的计算相关函数的方法越来越不能满足要求。文中介绍了时域和频域上计算m序列相关函数的原理和方法,并对2种方法进行了分析比较和仿真计算,得出基于FFT的频域算法大大减少运算次数和时间开销的结论。

The design and selection of expanding sequence are the critical technique in CDMA expanding communication systems. However, the calculation load will increase dramatically while the length of expanding sequence increases, and normal calculating method will not meet the demand. In this paper, principles of the calculation of m-sequence correlation function both in time do- main and frequency domain are introduced, which are then analyzed respectively and compared with each other. The result shows that the FFT-based method in frequency-domain outperforms the other one in calculation load and time.