Patent ID: 8213382

Claim:
A method for use by a multi-radio wireless communication system for controlling a handover of a mobile terminal between different radio access technologies, the method comprising the steps of: identifying a plurality of radio access technologies including a current radio access technology, and radio access technologies other than the current radio access technology, wherein the other radio access technologies and the current radio access technology having coverage areas covering a current location of the mobile terminal; classifying the plurality of radio access technologies into a plurality of similar sets of radio access technologies; assigning a fixed handover cost for each similar set of radio access technologies among the plurality of similar sets of radio access technologies, wherein the fixed handover cost applies to handover transitions between radio access technologies within a similar set of radio access technologies; for each other radio access technology identified: determining a performance gain between the current radio access technology and the other radio access technology covering the current location of the mobile terminal based on performance gain factors, determining a handover cost between the current radio technology and the other radio access technology based on handover cost factors that are dependent on characteristics of the radio access technologies, wherein the handover cost includes the fixed handover cost if the current radio access technology and the other radio access technology are classified in a similar set of radio access technologies, determining a handover cost-adjusted gain based on the performance gain and the handover cost, and controlling the handover based on handover cost-adjusted gain by: identifying, among the other radio access technologies, a particular radio access technology having a largest handover cost-adjusted gain, and triggering handover of the mobile terminal to the particular radio access technology having the largest handover cost-adjusted gain.