Two Kinds of All Phase Half-Band Filter and It's Application in the Filter Banks
Zhaohua Wang · Journal of Tianjin University Science and Technology · 2006
Two kinds of models and design methods of all phase digital filter based on frequency sampling method were proposed,therefore the theory of all phase digital filter was integrated.It was proved that the am- plitude frequency response of the all phase digital filters was between 0 and 1,no negative and zero phase.Ac- cording to the difference of filter length and frequency response vector,two kinds of all phase half-band filter (APHF)with no transition point are designed,when implementing spectrum factorization on APHF,there is no need to raise up the magnitude.Based on this two channel perfect reconstruction QMF can be designed with higher reconstruction accuracy,whose power complementary is 10~(-8) dB,while that of the traditional method is only 10~(-3) dB.