Apparatus for handover in TDMA communications

Abstract

A mobile communications system including a plurality of base stations includes a plurality of mobile telephones. Each mobile telephone communicates with at least a base station from the plurality of base stations using a timeslot and a frame. The frame has a plurality of timeslots for the base station to use to communicate with various of the plurality of mobile telephones in a cell covered by the base station. Each mobile telephone has a single radio capable of communication on various frequencies. The radio is not capable of communicating on different frequencies on adjacent timeslots in a frame. A mobile telephone may establish communication with a first base station on a particular timeslot in a frame. If another timeslot is available in the frame in a second base station, communication may be established with the second base station on another timestot in the frame. The another timeslot is not next to the particular timeslot if the frequency used on the particular timeslot and the another timeslot are different. If the frequencies used on the particular timeslot and the another timeslot are the same, communication may be established with the second base station on the another timeslot in the frame where the another timeslot is next to the particular timeslot or not next to the particular timeslot.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a divisional application of co-pending application Ser. No. 09 / 413,658 filed on Oct. 6, 1999 entitled Method and Apparatus Handover in TDMA Mobile Communications invented by Jan Vancraeynest, Attorney Docket Number U001 100087 (former docket no. 16296-706) which is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] This invention generally relates to cellular communications systems having mobile subscribers, and more particularly, to a method of controlling handover in the communications of cell site stations with a mobile unit in a TDMA cellular telephone system. [0004] 2. Description of the Related Art [0005] Cellular communications systems use a series of sites, known as base stations, to communicate with mobile subscribers. A mobile telephone unit typically communicates with the closest base station, or the base station having the best signal quality. A cellul...

AI Technical Summary

Benefits of technology

"The invention is a mobile communication system with multiple base stations and mobile phones. The mobile phones have a single radio and can communicate with different base stations on different timeslots of a frame. The system can adjust the quality of communication with the base stations based on signal quality, and the mobile phones can request communication with a second base station based on the signal quality of the first base station. The system can also allocate timeslots in the second base station for communication with the mobile phone. The technical effects of the invention include improved system reliability, better signal quality, and efficient use of system resources."

Problems solved by technology

Such a dual transceiver adds cost, size and power consumption, and reduced reliability to the mobile unit.

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