Regular M-band modulated orthogonal transforms

This paper aims to merge into an extended unique filter banks family the well-studied orthogonal 2-band solutions and all known M-band perfect reconstruction modulated filter banks. These new modulated orthogonal transforms give much more freedom in the design of the filter banks and suppress most of the limitations of the previously known modulated solutions. All unitary transforms can now be used for the “modulation” process, the prototype filter is not to be linear phase and furthermore it is possible to derive solutions which are both orthogonal and linear phase (for M>2). Furthermore it is easy to impose additional constraints so that for arbitrary M, the modulated orthogonal transforms should be considered as M-band orthogonal wavelets