Digital filters with adjustable bandwidth(s) are generally desirable in many applications like audio processing and telecommunication. This paper proposes a generalized Farrow structure for adjustable bandwidth linear-phase FIR filters designed under a minimax design criterion. The bandwidth of the proposed filter structure can be continuously adjusted with an updating routine that only involves a few multiplications and additions. Moreover, the generalized structure can be designed to effectively reduce the dynamic range of basis filter coefficients, which is desirable when making a fixed-point implementation on FPGAs.
Chenchi Luo, James H. McClellan