Communicating encrypted signals in which random bits and random bit position data are inserted

摘要

PCT No. PCT/JP95/01410 Sec. 371 Date Apr. 8, 1996 Sec. 102(e) Date Apr. 8, 1996 PCT Filed Jul. 14, 1995 PCT Pub. No. WO96/02992 PCT Pub. Date Feb. 1, 1996A transmitted signal is enciphered or concealed to thereby prevent interference, even when data indicative of the receiver terminal is made public because of the use of a common access channel. In the transmitter, in a random-number bit adder 6, a random-number alpha (digital signal) generated by a random-number generator 5 is inserted into a transmitting data signal DA generated by a transmitting data generator 1, and the resultant is outputted as a signal (DA, alpha ). An encipherment processor 2 enciphers the signal (DA, alpha ) and outputs it as a signal (DA, alpha )'. In the receiver, this signal (DA, alpha )' is deciphered into (DA, alpha ), and the random-bits PROPORTIONAL are removed from (DA, alpha ) to restore the signal DA.