A class of efficient recursive quadrature mirror filters for subband coding
A class of recursive quadrature mirror filters (QMFs) of the form H(Z)=N(Z)/D(Z/sup 2/) is proposed for subband coding. These filters can be efficiently designed with the iterative Remez exchange algorithm. Simple modifications are made to the Pei (see IEEE Trans. Circuits Syst., vol.CAS-36, no.2, p.311, 1989), Liang, McClellan, and Parks computer program for designing these recursive QMF filters efficiently. The resulting filters totally eliminate the aliasing terms and can achieve almost perfect magnitude reconstruction, with -131.5-dB distortion. A design example is presented to show the effectiveness of this approach. >