APPARATUS AND METHOD FOR MANAGEMENTING HYPER FRAME NUMBER FOR CIPHERING AND DECIPHERING IN MOBILE COMMUNICATION SYSTEM

摘要

It is arranged to prevent the damage of user data for a hyperframe number management method of encryption and the decoding in a mobile communication system and its primary device, by maintaining the hyperframe number in a kind of system and terminal samely. One ToA (timing adjustment) receiver (300) receives for from a node B.A ToA values of a CFN are corrected, a departure calculation part (302) calculates the offset between a CFN values, corrects according to ToA and one absolute CFN values. One encoding processor (306) changes or maintains a hyperframe number value to carry out the encryption of downlink data.