基于FFT的频分多波道分离和合成

FFT-Based Frequency Channel Separation and Combination

频分波道分离和合成是软件无线电应用于多信道收发的一项关键技术。本文将一些适于数字信号处理的技术,如快速傅利叶变换(FFT)和有限冲激响应(FIR)滤波器技术,引入波道的合成和分离,大大降低了运算的复杂度,使得这种技术有可能用通用的数字信号处理器来实现。对于一个10MHz带宽内的400路波道分离的情况,我们提出的方法要比传统的数字下变频的方法复数乘法次数少20～25倍。

Frequency channel separation and combination are key techniques to multi-channel transceiver under the conception of software radio. In this article,we applied amounts of digital sig nal processing, such as fast fourier transform (FFT)and finite impulse response (FIR) filter,into channel separation and combination. As the result of decreasing the quantity of multiplication oper ations, this method can be easily realized by general digital signal processor. For a 10MHz band of frequency,which contains of 400 frequency channel,this method can reduce the quantity of com plex multiplication by 20~25 times in comparison with the traditional digital down conversion method.