BIASED-CORRECTED RAKE RECEIVER FOR DIRECT SEQUENCE SPREAD SPECTRUM WAVEFORM

摘要

The performance of a RAKE receiver for indoor multipath WLAN applications ondirectsequence spread spectrum signals having relatively short codeword lengthscomprises achannel-matched filter and codeword correlator front end, plus a signalcombiner to which thecodeword correlation component is applied. The signal combiner is suppliedwith a bias-corrected input calculated by a distorted codeword signature (power)generator, which isoperative to generate and store a set of N codeword power correction values.The signalcombiner combines correction values into the codeword correlation for eachpotentiallytransmitted codeword S k. This serves to correct each correlation codewordmetric by a de-biasing power component ¦S k¦2 far the unequal multipath-based distortions ofthe codewordenergies. The output of the signal combiner is coupled to a peak detector,which selects aminimum distance-based 'de-biased' output as the transmitted codeword.