Patent ID: 8244245

Claim:
A portable telephone communication system comprising: a plurality of radio base stations having a notified information transmitting function of transmitting notified information including cell information managed by neighbor radio base stations to unspecific number of portable telephones; and a plurality of portable telephones having a cell selecting function of detecting a suitable cell on the basis of radio quality indicating suitability for communication, obtained from the received notified information, and selecting the cell as a cell to which the portable telephone itself belongs, wherein the plurality of radio base stations include both a radio base station of an upper-level version having a specific function and a radio base station of a lower-level version not having the specific function, a network is provided for transmitting a scrambling code list of the cells belonging to the radio base stations which correspond to a new function to the portable telephone on the basis of a code list transmitting function provided therein in advance, and each of the portable telephones has a code list requesting function of transmitting a request message to the network in order to obtain the scrambling code list, a function of managing undated neighboring cell information in which the cells belonging to the radio base station having the new function are updated by combining the neighboring cell information received from the radio base station with information of the scrambling code list transmitted from the network on the basis of the scrambling code list obtained from the network by transmitting the request message, and a mode selecting and setting function of selecting either an upper-level version communication mode in which only the radio base station of the upper-level version is an object of connection or a normal communication mode in which all of the radio base stations including both of the radio base stations of the upper and lower-level versions are objects of connection.