Patent ID: 7110379

Claim:
A radio communication method of a base station used for a radio communication system employing CDMA (Code Division Multiple Access) for radio access and providing multi-rate transmission, the radio communication system including a base station controller, a plurality of base stations, and a plurality of mobile stations, the base station being one of said plurality of base stations, the radio communication method comprising steps of: transmitting code information by message from the base station controller to one of the plurality of mobile stations, said code information for switching from a first code being used to a second code; transmitting timing information by message to the one of the plurality of mobile stations, said timing information including an integer representing a frame at which the first code is switched to the second code; switching from the first code to the second code at the base station in synchronization with switching from the first code to the second code at the one of the plurality of mobile station; and receiving a completion message from the one of the plurality of mobile stations indicating completion of switching from said first code being used to said second code at the one of the plurality of mobile stations.