Joint blind multipath diversity combining and PN code timing recovery for direct-sequence spread-spectrum systems

A RAKE receiver accomplishing joint blind multipath diversity combining and PN code timing recovery is proposed for direct-sequence spread-spectrum signaling over a frequency-selective fading channel. In this technique, an improved known modulus adaptive algorithm is exploited to perform multipath diversity combining in the blind mode, while a modified PN code timing recovery technique based on the timing error estimator extracts the finger error signals path by path independently. Taking the advantage of inherent diversity, this modified PN code timing recovery technique can efficiently combine finger error signals to avoid the problems with the drift or flutter effects in the timing error signals, and thus provide better code tracking performance as well. Extensive computer simulation results have verified the analysis and indicated very attractive performance of the proposed technique.