| 摘要 |
A random number sequence is generated and, in response to a discrete value produced from the sequence, an analog signal to be transmitted is scrambled to produce a first analog signal. The first analog signal and a second discrete signal produced by enciphering the random number sequence is combined, the composite signal being sent out to a receiver. At the receiver, a procedure opposite to that performed by the transmitter for combining the first and second signals occurs to separate the first analog signal and the second discrete signal. Decryption opposite to the encryption at the transmitter proceeds in response to a discrete value which is produced from a signal provided by deciphering the second discrete signal. <IMAGE> |
