Analysis of multiprototype over single prototype filter bank for non uniform filter bank

In this paper, an analysis of Multi-prototype based filter bank design over Single prototype based design for non uniform signal decomposition is done. The Multi-prototype based method reduces the number of channel combiners and residual errors when compared to Single prototype based channel combination technique. In both methods, the prototype filters with different pass-bands are optimized to have their 3dB frequency at π/(2M), where M is the number of sub-channels in the corresponding uniform filter bank. In the Single prototype based channel combiner method, Non uniform filter banks (NUFB) are generated by sub-channel merging whereas, in Multi-prototype method, NUFB with varying bandwidths is generated from multiple prototype filters, where M determines the granularity of the system. A rigorous analysis of both the methods is done and compared. The Multi-prototype based method is found to have less complexity and distortions as compared to the Single prototype channel combiner based approach. Simulations are done to obtain varying bandwidth channels, and analyzed for different input signals. The evaluation with various fidelity parameters and are found to be comparable with existing methods.