SYSTEM AND METHOD FOR EFFECTING SOFT HANDOFF BETWEEN FREQUENCY DIVISION DUPLEX AND TIME DIVISION DUPLEX COMMUNICATIONS SYSTEMS

摘要

PROBLEM TO BE SOLVED: To provide a system and method for controlling information transmission and a communication handoff between frequency division multiplexing (FDD) and time division multiplexing (TDD) communication systems using any multiple access scheme.SOLUTION: A mobile unit transmits information via a current one of a FDD and TDD communication systems while it moves toward the other, or targeted one of the FDD and TDD communication systems. A pilot search signal is generated by the targeted communication system, where the pilot search signal corresponds to a transmission range of the targeted communication system. A communication handoff is initiated from the current communication system to the targeted communication system when the mobile unit recognizes a predetermined threshold level of the pilot search signal. Concurrent communications are synchronized and temporarily maintained between the mobile unit and both the current and targeted communications systems using an increased data rate for each of the communications links.