An Analytic Signal Approach for Transmultiplexers: Theory and Design

A new non-FFT approach to transmultiplexer implementation is presented, based on the theory of the baseband analytic signal and on its successive allocation in the FDM format by appropriate digital interpolation and filtering. The method allows wide transition bandwidths to the filters, avoids the use of any product modulator, and leads to a channel-by-channel structure. As a design example, the application to the 12-channel FDM primary group is considered in detail, using FIR digital filters realized by 16 bit arithmetic standard digital circuits. The analysis and the computer simulation of the system performance are finally reported, showing the actual feasibility of the method for the transmultiplexer implementation.