ENCRYPTION METHOD, DECODING METHOD, ENCRYPTION SYSTEM, ENCRYPTION DEVICE, DECODER, STORAGE MEDIUM STORING ENCRYPTION PROGRAM AND STORAGE MEDIUM STORING DECODING PROGRAM

摘要

PROBLEM TO BE SOLVED: To attain encryption communication by chaos synchronization only through one transmission line by utilizing a signal for information also for a signals for synchronizing. SOLUTION: By employing a chaos dynamics system having parameters included in the system as a secret key, an irregular signal having orthogonality is generated, an information signal is multiplied with a plurality of the irregular signals generated from the chaos dynamics system, a plurality of the irregular signals multiplied with the information signal and irregular signals generated from other hidden dynamics system are summed to generate an irregular transmission signal being an encrypted text, and the transmission signal is fed back as an input signal to the chaos dynamics system. In the case that all parameter values being secret keys are coincident with those of the chaos dynamics system by which the encrypted text is generated, the same signals as the irregular signals synchronous with the chaos dynamics system included in the encryption device and generated in the encryption device are reproduced, the correlation between the signal generated by synchronization and the transmission signal is calculated and a binary information signal of the transmission signal is decoded.