Pollock, VandeSande and Priddy
Radio channel switching control method
 A radio channel switching control method for a digital mobile communication system employing TDMA techniques, in which a mobile station stores the synchronized state in the current channel, switches the current channel to a new one and performs a pull-in operation for a predetermined period of time and stores the synchronized state obtained by the pull-in operation. The mobile station establishes synchronism with the new channel by repeating a sequence of steps of performing communication again in the synchronized state in the current channel and performing the pull-in operation in the stored synchronized state for the new channel. Thus, it is possible to implement radio channel switching free from momentary interruption of communication, by maintaining communication in the current channel until synchronization with the new channel is established and communication is permitted. A common reference clock is applied to a plurality of pieces of radio equipment in a base station and each radio equipment obtains a synchronized state parameter for an arbitrary slot of the channel allocated thereto. When it is judged that channel switching is necessary, the synchronized state parameter in the current channel is set in the radio equipment of the new channel, by which the radio equipment of the new channel is caused to immediately start reception in the same synchronized state as in the current channel. 
Nippon Telegraph and Telephone Corporation
H H
H04W H04W
inventional additional
Toshinori Seizo Fumiyuki Akihiro Masaharu
Fujii Onoe Adachi Maebara Hata