| 摘要 |
The subject of the present invention is a method providing the means for recognizing the origin and/or the content of an RF signal without requiring substantial computation means, these recognition means being accessible only to authorized persons and being practically nonmodifiable and very difficult to detect by unauthorized persons, and this being so in various applications using RF signals transmitting information that is at least partly hidden. This method is characterized in that it spreads an item of information to be hidden with the aid of a hidden code, that it distributes, with the aid of an Exclusive OR function the information thus obtained in codes that are known with the aid of a hidden distribution algorithm, that, on reception, it applies the algorithm that is the inverse of that having served for the distribution in order to gain access to the spread code, that is correlates this spread code with the hidden code in order to find the hidden information. |
