Patent ID: 7218665

Claim:
A whitened front end for a tree-pruned multiuser detection (MUD) system, comprising: a parameter estimator coupled to a data stream providing estimation values of said data stream, wherein said data stream is an aggregate of a plurality of signals, and each signal is assigned a channel, and wherein said plurality of signals exceeds a number of signal space dimensions of said MUD, resulting in an overloaded condition; a filter bank having a plurality of filters coupled to said data stream and coupled to said parameter estimator, wherein each of said signals is individually coupled to said plurality of filters and produces a filtered output, and wherein said filters exceeds said number of signal space dimensions; a whitener designer coupled to said parameter estimator, wherein said whitener designer computes a whitener factorization for said signals, wherein the signals exceeds said number of signal space dimensions; an overloaded whitener unit coupled to said filter bank and said whitener designer, wherein said whitener unit applies said whitener factorization to said filtered output to produce a partially de-correlated and whitened output; and, a symbol-hypothesis testing section coupled to said whitener designer and said whitened output, wherein said symbol-hypothesis testing section uses a hypothesis pruning to perform a decision tree search.