Abstract: A multi-modal communication system and method capable of operating underwater, at an interface such as the surface of water, and in the atmosphere using a plurality of communication modes including optical, acoustic, and radio frequency communication. The nodes include underwater vehicles, divers, buoys, aerial vehicles, and shore-based operators. In one aspect, the system and method are capable of high-speed optical and long-range acoustic communication through transitioning between communication modes dependent upon signal conditions. It is another aspect to provide a system and method designed for clandestine operation that is not easily detected when in use.

Abstract: A system and method to reduce fouling of a surface subjected to an aquatic environment with a light source. According to one aspect, an antifouling system including an LED for emitting UV radiation, one or more mounts for directing emitted UV radiation toward the surface, and control circuitry for driving the LED disposed in a watertight housing. According to another aspect, an antifouling system which employs a fluorescent lamp disposed within a pressure vessel including a UV-transmissive material to allow UV light to pass through the pressure vessel and reduce bio-fouling of any surface.

Abstract: A system and method to broadcast an optical signal through an amorphous medium, including a primary emitter capable of producing a primary optical signal during at least one broadcast period and capable of transmitting the primary optical signal through the amorphous medium. A secondary emitter, separate from the primary emitter and in operation during at least a portion of the broadcast period, produces a secondary emission detectable by a detector during the broadcast period. A signal entrainment controller, in communication with the primary emitter and the secondary emitter, synchronizes the secondary emitter with the primary emitter to generate a resultant signal of higher intensity than the primary signal by itself.

Abstract: A system and method to broadcast an optical signal through an amorphous medium, including a primary emitter capable of producing a primary optical signal during at least one broadcast period and capable of transmitting the primary optical signal through the amorphous medium. A secondary emitter, separate from the primary emitter and in operation during at least a portion of the broadcast period, produces a secondary emission detectable by a detector during the broadcast period. A signal entrainment controller, in communication with the primary emitter and the secondary emitter, synchronizes the secondary emitter with the primary emitter to generate a resultant signal of higher intensity than the primary signal by itself.