A communication device encrypts symbols at a physical layer in order to improve encryption of data transmitted over a wireless link. A symbol mapper of the communication device receives a bit stream comprising multiple bits and maps the multiple bits to multiple symbols. An amplitude and phase adjuster of the communication device receives the multiple symbols and encrypts the symbols by applying at least one of a phase shift and an amplitude adjustment to each symbol of the multiple symbols to produce multiple encrypted symbols for transmission over a wireless link. In another embodiment of the present invention, a communication device is provided that is able to decrypt the encrypted symbols by applying at least one of a phase shift and an amplitude adjustment to each encrypted symbol that corresponds to a phase shift or an amplitude adjustment applied to the symbol by a transmitting communication device.