DATA RECEIVER

摘要

PURPOSE: To provide a data receiver suitable for charging for deciphering and storage of signals capable of receiving and deciphering or storing enciphered signals while protecting a copyright. CONSTITUTION: An arithmetic operation is performed to the initial value of a cipher separated in a reception separation circuit 111 in an arithmetic circuit 112 and a key signal is calculated. The calculated key signal is enciphered in an encipherment circuit 115 by using a user ID stored in a memory 113 and it is multiplexed with main data in a multiplex circuit 116 and recorded and stored in a data storage device 140. The signals inputted from the data storage device 140 are separated into the main data and the key signal in a separation circuit 117 and the key signal is deciphered by using the user ID of the memory 113 in a first deciphering circuit 118. Further, a pseudo random number is generated in a random number generation circuit 120 to which the key signal is inputted and the main data ciphered in a transmission station are deciphered in a second deciphering circuit 121 by using the pseudo random number.