In a wireless communication system, a secure communication link is provided by selecting a decoy data signal vector for transmission, generating a MIMO precoding matrix from a message to be sent; and multiplying the decoy data signal vector by the MIMO precoding matrix to construct a precoded signal vector. The MIMO precoding matrix produces information-bearing synthesized channel distortions in the transmitted signal. An undistorted version of the decoy data may be transmitted to an intended receiver. The receiver distinguishes between the synthesized information-bearing channel distortions and natural channel distortions to decrypt the information, while an eavesdropper would find it difficult to distinguish between natural and synthesized channel distortions in the signals it receives.