A secure communication system utilizes multiple “decoy” data signals to hide one or more true data signals. The true data signal(s) are encrypted, and received at a scrambling unit according to an original set of channel assignments. The channel assignments are optically switched with multiple decoy data signals to form a multi-channel “scrambled” output signal that is thereafter transmitted across a communication system. The greater the number of decoy signals, the greater the security provided to the open-air system. Further security may be provided by encrypting the decoy signals prior to scrambling and/or by utilizing a spatially diverse set of transmitters and receivers. Without the knowledge of the channel assignment(s) for the true signal(s), an eavesdropper may be able to intercept (and, with time, perhaps descramble) the open-air transmitted signals, will not be able to distinguish the true data from the decoys without also knowing the channel assignment(s).