A simple analytic design procedure for bireciprocal lattice wave digital filters (bireciprocal LWDFs) is presented with approximate linear phase. The design is started by replacing the odd order all-pass filter branch in the bireciprocal LWDF with a pure delay, leaving the other branch as an all-pass even function of z -2. Analytic design procedure is then formulated. Several design examples using such procedure are given for verifications.
Keywords: Bireciprocal LWDFs, All-pass sections, Half-band filters, Approximate linear phase.