NLMS adaptive FIR filter design method

This article presents a FIR filter design method which utilizes the NLMS (Normalized Least Mean Square) adaptive algorithm's system identification abilities. With such a method, any filters in hand including FIR, IIR or even analog ones can copy its responses to design the desired FIR filters. The FIR filter generated by such method can have the exact amplitude and phase responses with a target FIR filter which has a smaller or equal length, or obtain an amplitude response the same with an IIR or analog filter. In addition, it can design a FIR filter utilizing the structures' maximum, with a more excellent roll-off steepness and stopband attenuation than the traditionally designed FIR filter.