On Computational Complexity in Digital Transmultiplexer Filters

The quality standards recommended by the CCITT are the reference for the design of digital transmultiplexer filters. Their impact on filter specifications is analyzed, and expressions are given for the filter order, coefficient, and data word lengths in FIR and IIR approaches. Improvements on the polyphase filter bank design are pointed out, and the method is presented as a hybrid FIR-IIR technique. Finally, it turns out that the multiplication rate is the crucial parameter for complexity comparison between the approaches considered.