Patent ID: 6393287
Filing Date: 2002-05-21
Classification: H04W

Abstract:
A system for switching a speech channel between loosely coupled radio base stations, comprising:a radio base station control unit which allows a mobile telephone terminal to have a communication channel through a plurality of radio base station devices; and a radio base station which is provided with a field strength measurement-only channel which allows said mobile telephone terminal to measure the field strength of radiowave to reach said mobile telephone terminal; wherein said mobile telephone terminal measures the field strength in field strength measurement-only channel designated by said radio base station control unit and informs said radio base station control unit of the measurement results through said radio base station, and said radio base station control unit is provided with a hand off table for recording a soft hand off candidate station for said each radio base station, and an additional station search table for recording an additional radio base station that said candidate station is expected to next perform soft hand off, and regardless of the field strength, allows said mobile telephone terminal to have a speech channel to said additional station.