Chiman Kwan

1. Introduction 1.1. Overview of Digital Filters Digital filters are broadly categorized into finite impulse response (FIR) and infinite impulse response (IIR) filters [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22]. Each category presents its own set of advantages and disadvantages. FIR filters are renowned for their linear phase properties, but they have a drawback where they require a larger number of filter coefficients to achieve comparable cutoff frequencies [9].

1. Introduction Bandpass signals have been widely used in communications, sonars, radars, and software-defined radios. Since bandpass signals can have very high carrier frequencies, it is impractical to apply the Nyquist sampling rate to them.

Open AccessFeature PaperArticle by Mohammad Shahab Uddin 1, Chiman Kwan 2 and Jiang Li 1,* 1 Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23625, USA 2 Applied Research LLC, Rockville, MD 20850, USA * Author to whom correspondence should be addressed.