A Practical Design Approach to Decision Feedback Receivers with Conventional Filters

A method for designing conventional filters for decision feedback systems is described. Practical considerations, such as error propagation effect, timing inaccuracy and complexity, are incorporated in the design rules. In particular, non-band-limited noisy transmission channels and channels impaired by bandwidth limitation are investigated. In addition, noise and bandwidth limitations are taken into account simultaneously. The design approach is based upon polynomial descriptions which reveal simple relationships between the forward and feedback path, a stability measure which is representative of the error propagation, and an evaluation in terms of Laguerre polynomials. Results of simulations in hardware are given by way of a practical example and a binary regenerative transmission system for coaxial cables is studied.