On the Order Minimization of Interpolated Bandpass Method Based Narrow Transition Band FIR Filter Design

Design of hardware efficient digital systems has drawn appreciable attention of researchers over the last few decades. To this aim, this paper considers the design of a narrow transition band finite impulse response (FIR) filter operated in an interpolated bandpass filtering approach. An optimization problem is formulated that minimizes the complexity measure of the narrow transition band FIR filter under the constraints of length of the filter and normalized peak ripple magnitude (NPRM) threshold. Closed-form expressions for the optimal interpolation factor as well as the passband and stopband edges to obtain the narrow transition band are derived. A designed filter is subsequently implemented on Altera's Cyclone IV field programmable gate array (FPGA) chip and supremacy of the suggested design has strongly been established by correlating its hardware cost with many of the state-of-the-art FIR filters.