Traffic allocation and dynamic load balancing in a multiple carrier

Abstract

A wireless communication system provides wireless service to a mobile unit operating within a service area and includes a mobile switching center, at least one base station controller, a first plurality of base stations and a second plurality of base stations. The first plurality of base stations couple to the at least one base station controller and operate on a first carrier frequency. The second plurality of base stations couple to the at least one base station controller and operate on a second carrier frequency. The mobile switching center and the at least one base station controller operate to assign the mobile unit to at least one of the first plurality of base stations or at least one of the second plurality of base stations based upon available base station capacities. The wireless communication system may operate according to a code division multiple access protocol. In determining the capacity of the base stations, candidate base stations are first determined, with such candidate base stations selected based upon an operating location of the mobile unit. The candidate base stations include base stations from both the first plurality of base stations and the second plurality of base stations that could service the mobile unit at its present operating location. Once the candidate base stations are determined, capacity requests are sent to the candidate base stations. The base stations then respond with capacity responses. Based upon capacity responses received, the mobile unit is assigned to at least one of the first plurality of base stations or at least one of the second plurality of base stations. Operation may be undertaken when setting up a call or during the servicing of a call. During servicing of a call, operations commence upon receipt of a pilot signal strength measurement message received from the mobile unit.