A multiplex system for a small remotely manned submersible

The multiplex system described was designed for use on the NAVFAC Snoopy vehicle, a small remotely manned tethered undersea vehicle developed at the Naval Undersea Center. Using a combination of time division (TDM) and frequency multiplexing, the system allows simultaneous transmission of vehicle power, status, command, and video signals over a small diameter coaxial cable. Digital vehicle and status signals are TDM encoded, frequency modulated, and then transmitted via the tether cable to the vehicle (or control station) receiver. At the receiver the signals are frequency demodulated, TDM decoded, and sent to the appropriate function. The power and video signals are simply frequency multiplexed onto the tether cable, along with the frequency modulated command and status signals.