Continuous polynomials combination for the design of quadrature mirror filters

This material proposes an efficient method for the design of the two channel quadrature mirror filters (QMF) bank, by using continuous polynomial functions. It is important to know that linear phase FIR filters cannot exactly satisfy the power complementarity condition. The proposal is to approximate the amplitudes of the two frequency transition bands by using continuous polynomial functions. The result is a good frequency selectivity. In the proposed approach, the prototype filter is optimized, by using continuous polynomials in the transition band. Many simulation results are presented to sustain the proposed method.