Abstract:

In view of the critical shortcomings such as the design complexity and unsatisfactory performance of filter bank with the conventional windowing, a new approach is proposed to design a bank of prototype filtes with cosine modulated. In the proposed method, the prototype filter is optimized by using the windowing technique, with the novelty of exploiting spline functions in the transition band of the ideal filter, it relaxes the perfect reconstruction limitation, the design problem of cosine modulated filter bank is formulated as nonlinear unconstrained optimization of objection functions. Then a quantumbehaved particle swarm optimization algorithm is used to optimize objective functions, thus getting the optimal solution stopband cutoff frequency, and the prototype filter is designed. The simulation results demonstrate that the proposed method gives a better performance than the conventional design method in terms of amplitude distortion, aliasing distortion, and signaltonoise ratio and reconstruction error, and the cosinemodulated transmultiplexer with the proposed technique has a good performance in the application of communications.