Patent ID: 7417975

Claim:
A cellular system in a code division multiple access mode comprising: a mobile station for measuring reception quality of pilot signals transmitted by a plurality of base stations and setting up radio links; and a base station control unit for assigning unique information to the base stations there under and determining sequence information on the assignment, wherein each of said base stations is operable to check a code word transmitted from the mobile station having the radio link set up and associated with said base stations unique information against a table created based on information notified by the base station control unit and determine a transmitting base station, wherein: said base station control unit has means for notifying each base station of said base stations, in advance, of said unique information and said sequence information; and each of said base stations has means for judging whether or not each of said base stations itself is specified as the transmitting base station by creating in advance code word candidates configured to be transmitted by the mobile station based on said unique information and said sequence information and checking the code word received from the mobile station against said code word candidates.