Constraint two-path polyphase IIR filter design using downhill simplex algorithm

The paper addresses the design of the polyphase IIR filters based on the N^th-order single-coefficient allpass sub-filters in the constraint coefficient space using the Constraint Downhill Simplex Algorithm (CDSA). incorporating the bit-flipping algorithm in its core engine allowed the optimisation routine to converge to better target designs without affecting the high speed of the original algorithm. Establishing the boundaries of the search space required by the Downhill Simplex Algorithm (DSA) for the two-path polyphase IIR filter is also presented