METHOD AND APPARATUS FOR SECURING WIRELESS COMMUNICATIONS

摘要

A method and apparatus for securing wireless communications are disclosed. A watermark message is encoded to watermark message symbols. A cover message is encoded to cover message symbols. The watermark message symbols are then overlaid onto the cover message symbols to generate a watermark-embedded cover message in a physical layer. The watermark message symbols have a substantially lower amplitude than the cover message symbols. Thus, the watermark message introduces small perturbation around the constellation points of the cover message symbols. The watermark message symbol may span or spread over a plurality of cover message symbols and may be encrypted with a secret key. The watermark message is used for improving receiver performance by transmitting additional information or for security enhancement purposes. The watermarking function may be selectively turned on and off.