Abstract:

In the paper,a new design method of near-perfect-reconstruction cosine modulated filter banks is proposed,the prototype filter is designed by optimization method which fixes the prototype filter stopband cutoff frequency,takes passband cutoff frequencyas a parameter variable,optimizes the target function which meets reconstruction condition,designs indirectly the prototype filter,and then obtains the cosine modulated filter banks by modulation.It appropriately relaxes the limit conditions of perfect reconstruction of CMFB,so obtains lower complexity and computing time.The simulation results demonstrate that the method proposed is simple and effective,can obtain high stopband attenuation,low aliasing distortion and reconstruction error banks.

Key words: near-perfect-reconstruction, cosine modulated filter banks, prototype filter, QPSO