Patent ID: 6075807
Filing Date: 2000-06-13
Classification: H04B

Abstract:
A digital matched filter for a CDMA radio system comprises:a digital delay line having a plurality of successive delay stages adapted to receive a multiple bit digital signal and propagate said digital signal therethrough at a fixed rate;a correlator coupled to said digital delay line to correlate said digital signal to a predefined spreading code to provide a plurality of signals indicating correspondence between individual bits of said digital signal and respective chips of said spreading code;a summing device coupled to said correlator to combine said plurality of signals into a summed signal representing a degree of correlation of said digital signal to said spreading code; anda window control unit operatively coupled to said summing device to enable operation of at least one of said correlator and said summing device only during discrete time periods of said summed signal having a high degree of correlation of said digital signal to said spreading code, and disable operation of at least one of said correlator and said summing device between said successive ones of said discrete time periods.