Transmission of Multiplexed PAM Signals Over Multiple Channel and Diversity Systems

It is well known that the optimum receiver for pulse-amplitude-modulated (PAM) signals, transmitted over a single channel, consists of a cascade of continuous and transversal filters. It is shown that an extended structure of this type is also optimum for the completely general case of multiplexed PAM signals transmitted over random-time and frequency-dispersive multichannel systems with inputs and outputs, where each output is subjected to arbitrarily correlated additive noise. The random channels may also be arbitrarily correlated. In general, the receiver consists of continuous filters and tapped delay lines with M²sets of taps. An adaptive version is also described. The results include, as special cases, the situations considered by Gonsalves and Tufts [8], Shnidman [5], and Kaye [3]. Also, included as special cases are new results for diversity systems, multi-input systems such as multipair cables, and multiple-terminal systems such as multiple access repeaters in which cochannel interference occurs.