A method of designing cosine-modulated 2D perfect reconstruction FIR filter banks with linear phase

This paper proposes a new method for designing cosine-modulated 2D perfect reconstruction FIR filter banks with a linear phase. In conventional cosine-modulated perfect reconstruction filter banks, although the prototype filters have linear phase, it is impossible to obtain linear phases in analysis and synthesis filters. In this paper, the analysis and synthesis filters with linear phases are realized by using a new decomposition scheme. In this scheme, the input signal is decomposed into D+1 subbands in the frequency plane, while the system has 2D channels. These D+1 filters are obtained by cosine modulation of the prototype filter. The remaining D-1 filters are obtained by sine modulation and support the same bandwidth as the cosine-modulated bandpass filters. In this case, the filter bank can satisfy the perfect reconstruction condition by applying certain condition to the prototype filter. The effectiveness of the present method is verified through a design example.