A NEW APPROACH TO THE DESIGN OF DISCRETE COEFFICIENT FIR DIGITAL-FILTERS

In this correspondence, the iterative Lagrange multiplier approach is proposed for designing discrete coefficient FIR digital filters. The m ethod associates the conventional Lagrange multiplier approach and a t ree search algorithm, For each branch of the tree, the Lagrange multip lier approach is used to optimize the remaining unquantized coefficien ts of the designed FIR filter in the least-squares sense when one or m ore of the coefficients takes on discrete values, Design examples. inc luding general low-pass filters and Nyquist filters, are presented to demonstrate the effectiveness of the method, Also, the method can be e xtended to design discrete coefficient 2-D FIR filters.