DESIGN OF AN ANTI-ALIASING LOW PASS FILTER

Abstract: In this paper an anti-aliasing low pass filter is designed for removal of aliasing. The proposed method extends an existing fundamentally novel approach to the design of anti-aliasing filter, termed filtering by aliasing, incorporates the frequency domain aliasing operation itself into the filtering task .The spectral content is spread with a periodic mixer and weighted with a sample analog filter before it aliases at the sampler. By designing the system according to the formulation presented in the proposed method, the sampled output will have been subjected to sharp anti-aliasing filtering. This describes the proposed filtering by aliasing idea, the design, and its range of frequency response. It also provides a performance comparison against existing techniques in the context of reconfigurable anti-alias filtering.

Keywords: filtering, anti-aliasing, software defined radio, cognitive radio.