一种改进的软件无线电FM信号解调方法

An Improved Demodulation Method of FM Signals on Software Defined Radio

摘要: 为提高软件无线电FM信号处理速度，对现有FM解调方法作了三点改进。一是使用快速反正切算法提取复信号的相位，二是优化复信号相位去卷绕算法，三是基于FIR滤波器系数的对称性优化低通滤波操作。实践证明改进后FM信号的解调速度可提高到原来的两倍以上，新方法的实用性强，已应用于软件无线电FM信号处理的工程实践中。

Abstract: In order to improve the signal processing speed of FM signals on software defined radio, three improvements have been made to the existing FM demodulation methods. One is to use a fast arctangent algorithm to extract the phase of a complex signal, the other is to optimize the phase unwrapping algorithm of the complex signal, and the third is to minimize the low-pass filtering operation based on the symmetry of the FIR filter coefficients. The practice demonstrates that the FM signal demodulation speed of the improved method can be increased to more than twice of the original one, and the new method has strong practicability, which has been applied to the engineering practice of FM signal processing on software defined radio.