A method is provided for encryption/decryption for secure the privacy of the information flow between two communicating nodes, and authentication to establish the identity of the communicating nodes in digital communications systems. A common secret or encryption key is generated at the two nodal ends of the communication link without prior dissemination. The authenticity of the communicating entities are maintained over time based on unique non-idealities of the communicating nodes in conjunction with the propagation characteristics of a link between them.
Full Patent: Radio Scene Encryption And Authentication Process