| 摘要 |
The objective of the invention is to provide an encoding method and a communication method wherein a bit error correction is easy for an authorized recipient but difficult for an unauthorized recipient. A transmission path along which bit errors are moderately controlled is used to transmit/receive a random number sequence. A common key is shared by a transmitter and a receiver in advance; the bit values of the common key are caused to correspond to the respective slots of the random number sequence; the common key is used to divide the random number sequence into two or more random number system sequences on the basis of the correspondences; and for each of the random number system sequences, an encoding is performed and a parity check signal is generated. The unit of the encoding is equal to or greater than the length of the common key so as to make a segment analysis by an unauthorized recipient impossible. |
