Patent ID: 7492754

Claim:
A method for a soft handoff operation in a WCDMA communication system, comprising: transmitting data frames from a first base station to a mobile station in accordance with a first downlink data frame time offset, wherein said first downlink data frame time offset is set from a channel frame timing of the first base station; measuring a first observed downlink time offset experienced at said mobile station between a first downlink transmission received from said first base station and an uplink timing; measuring a second observed downlink time offset experienced at said mobile station between a second downlink transmission received from a second base station and said uplink timing; communicating said measured first and second observed downlink time offsets from said mobile station to at least a base station controller in communication with said first and second base stations; determining a second downlink data frame time offset based on said measured second observed downlink time offset, wherein said second downlink data frame time offset is set from a channel frame timing of the second base station, wherein said first and second downlink data frame time offsets are in increments of a predetermined number of chips time; communicating said second downlink data frame time offset to said mobile station for said soft handoff operation; transmitting data frames from said second base station to said mobile station in accordance with said second downlink data frame time offset, wherein data frames transmitted from said first and second base stations carry the same data symbols for said soft handoff operation; adjusting timing of a time offset adjuster in said mobile station for adjusting data symbols timing according to said first and communicated second downlink data frame time offsets for identifying corresponding data symbols in transmitted data frames from said first and second base stations for said soft handoff operation, wherein said soft handoff operation includes soft combining said identified corresponding data symbols.