| 摘要 |
PURPOSE:To enhance the ciphering performance by dividing a signal of a segment of each time slot in terms of frequencies and sending the signal at a different time from a sub slot included in each time slot. CONSTITUTION:A radio base station 30 attains the communication between a telephone network 10 and n-sets of mobile radio equipments 100-1-100-n by time division time compression multiplexing. In the case of the communication to mobile radio equipments 100-1-100-n in the radio base station 30, n-sets of time slots comprising analog signals subject to time division compression are sent. That is, a signal used for the communication between the mobile radio equipment 100 and the radio base station 30 is divided into plural frequency bands and each is compressed by a different time compression ratio to replace, allocate and cipher the sequence of sub slots included in each time slot, and the result is sent, and a receiver side releases the ciphering to decode an original signal. Thus, the reception of a 3rd party not knowing the division of the frequency band, time compression ratio and the replacement sequence is disable. |
