초록 ▼

A method and apparatus for performing an inter-system soft handoff is described. In accordance with the present invention, when a subscriber unit crosses from a first cellular system to a second cellular system, a base station controller determines if sufficient network resources are available to co

A method and apparatus for performing an inter-system soft handoff is described. In accordance with the present invention, when a subscriber unit crosses from a first cellular system to a second cellular system, a base station controller determines if sufficient network resources are available to conduct a inter-system soft handoff. If so, the base station controller generates a set of signaling messages that cause call processing resource to be allocated and for the call to be processed at the second cellular system. The base station controller then perform data-selection and data-broadcast for the call by transmitting data to the subscriber unit by way of the second cellular system as well as via one or more base stations to which the base station controller is directly coupled. The determination as to whether sufficient network resources are available to conduct the inter-system soft handoff is based on the type of connection that exists between the first cellular system and the second cellular system, the number of inter-system calls being conducted, and the frame offset of the call currently being processed.

대표청구항 ▼

[ We claim:] [1.] A method for conducting an inter-system soft handoff of a call made by a subscriber unit between a first cellular system and a second cellular system comprising the steps of:a) notifying the first cellular system that the subscriber unit is entering the second cellular system;b) de

[ We claim:] [1.] A method for conducting an inter-system soft handoff of a call made by a subscriber unit between a first cellular system and a second cellular system comprising the steps of:a) notifying the first cellular system that the subscriber unit is entering the second cellular system;b) determining if sufficient network capacity exists in an interconnection between the first cellular system and the second cellular system to conduct the inter-system soft handoff including the substeps of:b.1) querying said second cellular system via a query message;b.2) receiving a second total number of inter-system calls from said second cellular system indicating a number of calls anchored at said second cellular system and having said first cellular system as a target cellular system;b.3) summing said second total with a third total of inter-system calls anchored at said first cellular system and having said second cellular system as the target cellular system to yield a first total number of inter-system calls; andb.4) determining if sufficient network capacity exists between said first cellular system and said second cellular system based on a total capacity and said first total number of inter-system calls; andc) establishing a call channel between the first cellular system and the second cellular system if sufficient network capacity exists; andd) transmitting a first instance of forward link data received at said first cellular system to the subscriber unit by way of a first radio frequency signal interface between the subscriber unit and the first cellular system, and transmitting a second instance of forward link data to the subscriber unit by way of the second cellular telephone system and a second radio frequency interface between the subscriber unit and the second cellular system.