Underwater camera unit and surface controller

A surface controller for controlling an underwater camera unit via an underwater cable comprising two wires, the surface controller comprising:

• a power supply circuit configured to supply a DC supply voltage;
• a connector coupled to the power supply circuit, configured to connect the surface controller to the underwater cable to couple the surface controller to the underwater camera unit, to transmit control and/or monitoring signals and supply the DC supply voltage via the underwater cable and to receive image data multiplexed with control and/or monitoring signals via the underwater cable;
• a modem coupled to the connector;
• a processor configured to generate and process control and/or monitoring signals, wherein the processor is coupled to the modem;
• and
• an interface configured to pass image data to image display/recording equipment, wherein the interface is coupled to the modem,
• wherein the modem is configured to:
• receive the image data multiplexed with control and/or monitoring signals via the connector,
• de-multiplex the image data and the control and/or monitoring signals;
• pass the de-multiplexed image data to the interface;
• pass the de-multiplexed control and/or monitoring signals to the processor;
• and
• receive the control and/or monitoring signals generated by the processor and pass them to the connector for transmission to the underwater camera unit via the underwater cable, and
• wherein the image data and the control and/or monitoring signals are superimposed on the DC supply voltage on the underwater cable.

A method of operating an underwater camera unit, the underwater camera unit comprising:

• a pressure housing containing:
• a modem;
• a command processor coupled to the modem to receive control signals from the modem;
• an image processor coupled to the modem to provide image data to the modem;
• a camera sensor coupled to the image processor;
• and
• a power supply circuit;
• and
• a connector for connecting the underwater camera unit to an underwater cable comprising two wires, to receive control and/or monitoring signals and a DC supply voltage via the underwater cable and to transmit multiplexed image data and control and/or monitoring signals via the underwater cable comprising two wires,
• wherein the modem is coupled to the connector,
• wherein the method comprises:
• multiplexing image data from the image processor with control and/or monitoring signals from the command processor and transmitting the multiplexed image data and control and/or monitoring signals from the underwater camera unit via the connector by the modem;
• and
• receiving control and/or monitoring signals via the connector and passing them to the command processor by the modem;
• and
• receiving the DC supply voltage from the underwater cable via said connector by the power supply circuit, and
• wherein the image data and the control and/or monitoring signals are superimposed on the DC supply voltage on the underwater cable.

A method of operating a surface controller for controlling an underwater camera unit via an underwater cable comprising two wires, the surface controller comprising:

• a power supply circuit;
• a connector coupled to the power supply circuit, configured to connect the surface controller to the underwater cable to couple the surface controller to the underwater camera unit, to transmit control and/or monitoring signals and supply a DC supply voltage via the underwater cable and to receive image data multiplexed with control and/or monitoring signals via the underwater cable;
• a modem coupled to the connector;
• a processor configured to generate and process control and/or monitoring signals, wherein the processor is coupled to the modem;
• and
• an interface configured to pass image data to image display/recording equipment, wherein the interface is coupled to the modem,
• the method comprising:
• receiving image data multiplexed with control and/or monitoring signals via the connector by the modem;
• de-multiplexing the image data and the control and/or monitoring signals by the modem;
• passing the de-multiplexed image data to the interface by the modem;
• passing the de-multiplexed control and/or monitoring signals to the processor by the modem;
• receiving control and/or monitoring signals generated by the processor;
• and
• passing the control and/or monitoring signals to the connector for transmission to the underwater camera unit via the underwater cable;
• and
• supplying the DC supply voltage to the underwater cable by the power supply circuit via said connector,
• wherein the image data and the control and/or monitoring signals are superimposed on the DC supply voltage on the underwater cable.