Regularisation Procedures for Iterated Recursive Digital Filters

Abstract

In a previous paper presented at the 1994 International Symposium on DSP for Communication Systems [1] we described the problem of pipelining feedback systems such as IIR digital filters for high-speed communication systems. The throughput speed appears at first to be constrained in a fundamental way by delays through multipliers in the feedback loops. As shown by Messerschmitt and others, however, this problem is not, in fact, a fundamental one: but can be circumvented by use of the “Messerschmitt transformation”, in which a multiply-iterated version of the system equation is used as the basis of the implementation, rather than the original uniterated equation.