Mobile-assisted handoff technique

A method of performing handoff of a mobile in a mobile cellular communications system, the system comprising a mobile communicating with a serving base station, there also being a plurality of adjacent base stations transmitting signals, wherein the method comprises the steps of:

• monitoring by the serving base station quality of communication with the mobile;
• measuring by the mobile signals received from the adjacent base stations to give mobile signal measurements;
• reporting the mobile signal measurements to the serving base station;
• adjusting at least some of the reported mobile signal measurements to predict signal measurements that the adjacent base stations would make of signals received from the mobile to give a set of predicted signal measurements;
• comparing, in response to the quality of communication with the mobile changing, at least the set of predicted signal measurements so as to select a preferred adjacent base station associated with the best signal measurement and,
• handing off the mobile to the preferred base station.

A mobile cellular communications system comprising a mobile communicating with a serving base station, there also being a plurality of adjacent base stations transmitting signals, wherein:

• the mobile includes measuring means to measure signals received from the base stations and reporting means to report the signal measurements to the serving base station, and
• the network further includes:
• computing means to predict, from the signal measurements reported by the mobiles, signal measurements that the adjacent base stations would make of signals received from the mobile to give a set of predicted signal measurements;
• comparison means to compare at least the set of predicted signal measurements and to select a preferred base station associated with the best signal measurement.