Quadrature mirror filter design by Chebyshev approximation
Wen-Thong Chang, Ming-Shing Lin · 2002
The design of a half-band filter for subband coding systems is discussed. The characteristics of both the time and frequency responses of the half-band filter are used in order to reduce the computation time and increase the computation accuracy. The constraint for such a filter is that the even terms of its impulse response must be zero in order to meet the requirement of a uniform frequency response for the whole system. An algorithm based on the Chebyshev approximation that utilizes only odd-symmetry polynomials for frequency interpolation to meet the required frequency response of the half-band filter is proposed.>