Analysis and design of periodically time varying digital filters

This paper describes a type of periodically time varying (PTV) digital filter. Such a filter of period M, simulates the response of a bank of M bandpass filters with their outputs connected to a rotating switch, and requires less multiplications per output sample. A theoretical analysis of the filters is presented, followed by a description of a method of design. A design of a 12-channel filter for use in transmultiplexing is considered.