Recursive digital filter design with linear phase

The application of linear programming to the design of recursive digital filters is considered. Usually the question of filter stability is solved either heuristically or by incorporating sufficient but not necessary linear stability constraints in the problem approximation. A different approach to solve the problem of stability is proposed. As an example, the proposed approach to stability is applied to the recent method of A.T. Chottera and G.A. Julien (1982) which uses a simultaneous approximation of given magnitude and linear phase characteristics. It is shown that it leads to a drastic reduction in both computation time and data volume. Comparative examples of design are presented illustrating the improvement achieved