采用过渡带补偿方式的FIR滤波器设计

FIR Digital Filter Design Using Transition Band Compensation Method

提出一种窄过渡带和中等过渡带宽FIR数字滤波器的设计方法,它以频率响应掩蔽思想为基础,采用过渡带补偿方式,将一个滤波器分解成几个过渡带较宽的低复杂度子滤波器来进行设计,能够达到与频率响应掩蔽技术相当的复杂度。若将半带滤波器作为过渡带补偿设计方法中的原型滤波器,则能比最初的频率响应掩蔽方法使用更少的乘法器。本文同时给出插值因子的估计方法,并分析了各个子滤波器对总滤波器纹波的影响。

A method for designing narrow and moderate transition band width FIR digital filter is proposed. Based on the idea of frequency-response masking, the method uses a transition band compensation trick and divides a single filter into several wide transition band width subfilters with the lower complexity. It can obtain almost the same complexity compared with the original frequency-response masking technique. If a half-band filter is used as a prototype filter in the proposed method, even more multipliers can be saved. This paper also gives the method for estimating the up-sampling ratio and analyzes effects on overall filter ripple of sub-filters.