A novel approach to the design of oversampling complex-modulated digital filter banks

This paper addresses the minimisation of the overall disturbances of the output signal of an oversampling DFT subband-coder filter bank. These disturbances are separated into aliasing and imaging. By means of the definitions of these disturbance components, two quadratic functions are derived that are used as objective functions in the design approach. The algorithm optimises in an iterative manner the coefficients of the prototype filters of the analysis and synthesis filter banks. It is proved that the design problem is convex. An efficient implementation of the algorithm is given. A numerical example shows that the output disturbances are highly reduced compared to standard designs.