Patent ID: 6456608
Filing Date: 2002-09-24
Classification: G06F,H03H,H04B,H04J,H04L,H04N,H04W,Y02D

Abstract:
A pilot adaptive vector correlator for correcting phase rotation of a plurality of received-multipath signals of a spread-spectrum signal having a pilot-spreading-code signal, comprising:pilot-despreading means for generating a plurality of replicas of the pilot-spreading-code signal, with each of the plurality of replicas of the pilot-spreading-code signal having a different phase, said pilot-despreading means for despreading, using the plurality of replicas of the pilot-spreading-code signal, the plurality of received-multipath signals of the spread-spectrum signal as a plurality of despread-multipath signals; said pilot-despreading means thereby generating a noise-power level when each pilot-spreading-code signal embedded in each of the plurality of received-multipath signals of the spread-spectrum signal is not in phase with any of the plurality of replicas of the pilot-spreading-code signal; said pilot-despreading means thereby generating one or more detected-pilot signals, when one or more pilot-spreading-code signals embedded in the received-multipath signals of the spread-spectrum signal is in phase with one or more of the plurality of replicas of the pilot-spreading-code signal, respectively; a pilot adder for combining a plurality of weighted-despread-multipath signals, as a combined-pilot signal; phase-locked means, coupled to said pilot adder, for phase locking to the combined-pilot signal and for generating, from the phase-locked combined-pilot signal, a derotation-phaser signal; correction means, coupled between said pilot-despreading means, said phase-locked means and said pilot adder, for multiplying and filtering each of the plurality of despread-multipath signals by the derotation-phaser signal, thereby generating a plurality of weighting signals, respectively; said correction means for multiplying the plurality of despread-multipath signals by the plurality of weighting signals, to generate the plurality of weighted-despread-multipath signals, respectively; acquisition-decision means, coupled to said pilot-despreading means, responsive to the one or more detected-pilot signals from said pilot-despreading means, for determining whether the one or more detected-pilot signals are synchronized to one or more of the plurality of replicas of the pilot-spreading-code signal; said acquisition-decision means, responsive to detecting no synchronization, for sending a control signal to said pilot-despreading means, for offsetting the phase of one or more of the plurality of replicas of the pilot-spreading-code signals; and said acquisition-decision means, responsive to detecting synchronization, for maintaining synchronization between the plurality of received-multipath signals and the plurality of replicas of the pilot-spreading-code signal.