Computer aided design of FIR digital filter

Abstract

The use of optimization technique for designing digital filters is of widespread practice. For a given order, filters designed by using the iterative methods can closely approximates the 'best' filter for that order than by using other methods. In the present work, a design technique using Hooke and Jeeves pattern search technique has been implemented. The design procedure .is based on frequency sampling method. Optimization technique has also been implemented to define the transition region of the desired filter to maximise the stop band attenuation. An algorithm has also been presented which gives the solution for designing a filter, when the pass band and stop band frequencies and maximum tolerable deviations in pass band and stop band are given but the order of the filter is not given. The developed design technique has been implemented on a IBM 4331 Computer using FORTRAN language