基于有限脉冲变换的FIR滤波器进化设计

Evolutionary Design of FIR Filter Based on Finite Impulse Transform

结合 FIR傅里叶级数设计法和窗函数的基本原理 ,提出先将 FIR滤波器的脉冲系列自由分布于 - 1～ 1之间 ,然后优化求逆 ,获得预期 FIR滤波器特性的新思路 .根据预期频率特性的指标要求 ,建立脉冲值的优化模型 ,通过遗传算法来求解 .所得的优化解 ,使对应 FIR滤波器的频率特性较好地满足预期频率特性的要求 .该设计具有方法简单、自由度高。

For anticipating FIR filter characteristics, the author put forwards a new idea which makes the impulsle series of FIR filter to distribute freely in the range of -1～1 at first and then makes optimization and inversion. The new idea is obtained by refering to the basic principle of FIR fourier series design and window function. Based on the target demand of anticipating frequency characteristic, a model for optimizing impulse value is built and the solution is obtained by genetic algorithm. The optimined solution so obtained will make the frequency characteristic of FTR filter meet the demand of target frequency characteristics to a great extent. The author's design is simple in method,high in free degree,flexiblity and robustness.