MODULATION AND ENCRYPTION OF A DIGITAL DATE STREAM, METHOD OF DECODING, MULTI-CARRIER TRANSMISSION SYSTEM

摘要

Method of modulating a digital data stream in MC technology, in which the constellation points (Xo, X1 ... XN-I) change their sequence in accordance with a mapping pattern (Psii) during modulation. This dynamic mapping represents an encryption, since it is not readily possible for an unauthorized subscriber to restore the original sequence. The encryption level is further increased by the use of a set of multiple mapping patterns (Psii), which is implemented during transmission in the form of a loop. The encryption level is further increased by defining a hop interval (Ihop), indicating the validity of an individual mapping pattern, after the handshake. The encryption key defines a set of mapping patterns (Psii), a permutation function (Si), which indicates the order of use of the individual elements of the set of mapping patterns, and a hop interval (Ihop).