Design and development of c.c.d programmable transversal filters

This paper examines the potential of integrated-circuit-based programmable transversal filters for baseband operation. The emphasis is on compact processors with an eventual aim of a single chip, monolithic (design suitable for a variety of signal-processing applications. Before hardware developments are treated, trade-offs between serial and parallel configurations of convolver are considered, together with their respective component requirements. It appears that for complete integration of a transversal filter module, the parallel approach is preferred. A study is made of the circuit elements of a particular realisation of an integrated analogue convolver in c.c.d./m.o.s. technology. All aspects of the design are considered and the description is focused around a prototype 64-stage programmable transversal filter. Several such units could be cascaded giving this integrated approach an enormous potential in applications where space and power are crucial, and high computing precision is not essential.