Cancellation of pilot and unwanted traffic signals in a CDMA system

摘要

The present invention relates to a global pilot signal canceller (61) for use in a receiver that receives communication signals from a transmitter over a CDMA air interface that removes the global pilot signal from a desired traffic signal prior to decoding, characterized in that the canceller comprises an input (63) for receiving the communication signals and a system output (Oadd); said input coupled to a global pilot despreader (65) and a desired traffic signal despreader (91) each having a summed output; a desired traffic signal and global pilot cross-correlation means; said global pilot despreader (65) output (Oad1) coupled to a pilot strength determining means, said determining means having an output (Opm); said pilot strength determining means output (Opm) multiplied with said cross-correlation means output (Oad2) where said cross-correlation means comprises; a global pilot signal code generator; a desired traffic signal complex conjugate code generator; a mixer for cross-correlating said global pilot signal code and said desired traffic signal complex conjugate code; and a sum and dump processor for summing over time said cross-correlation product; and