US Patent 8064398 Seamless interfrequency handoff in a high data rate wireless system

A high data rate system capable of inter-frequency handoffs with little or no interruption in data service. The access network sends data from the first sector to the access terminal at the first frequency. The access terminal measures a parameter of a signal received at the access terminal from the second sector at the second frequency, wherein a pre-active set of the access terminal includes the second sector, and wherein an active set of the access terminal consists of one or more sectors operating in the first frequency. The access terminal then sends a data source control message corresponding to the second sector to the access network, after which the access terminal switches the pre-active set and the active set.