Abstract: An underwater communication method is provided. EM signals are transmitted via a seabed using an underwater electrically insulated magnetically coupled antenna. By making use of the low loss properties of the seabed, EM signal attenuation can be reduced and consequently the transmission range can be increased. The underwater electrically insulated magnetically coupled antenna may be located within a body of water or may be buried in the seabed.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver that has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver that has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: An underwater communication system comprising a transmitter for transmitting information using an electromagnetic and/or magneto-electric transmit antenna and a receiver for receiving information using an electromagnetic and/or magneto-electric receive antenna, at least one of the transmit and receive antennas comprising a plurality of antenna elements which collectively use field superposition and interference to form composite field patterns, beams or shapes and wherein one or both the transmit antenna and receive antenna are underwater.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver that has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: An underwater navigation system comprising a transmitter having an electrically insulted magnetic coupled antenna for transmitting an electromagnetic and/or magneto-inductive signal, a receiver having an electrically insulated magnetic coupled antenna for receiving an electromagnetic and/or magneto-inductive signal from the transmitter, and determining means for determining the position of the receiver relative to the transmitter using the received electromagnetic and/or magneto-inductive signal.

Abstract: An underwater remote sensing system comprising a transmitter for transmitting an electromagnetic signal, a receiver for receiving an electromagnetic signal reflected from an object and determining means for determining the location of the object, wherein at least one of the transmitter and receiver is underwater. The determining means may be operable to determine the location of the object using signals received at three or more receiver positions. To do this, three or more receiver antennas may be provided. Alternatively, a single receiver antenna may be provided and moved between three or more different measurement locations.

Abstract: The present invention relates to an underwater guidance system for guiding an underwater apparatus, for example an underwater vehicle, towards a target structure, such as a docking station. The system comprises at least one system for capturing or sensing information on the relative position of the apparatus and the target structure and/or at least one imaging system for capturing an image of the target structure and a transmitter for wireless electromagnetic transmission of data indicative of the position information and/or captured image to the underwater apparatus or an underwater apparatus controller.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver that has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: The present invention relates to a connector system that provides the transfer of electrical power and/or data communications signals between two systems. The connector has no conductive electrical connection and can operate independently of angular orientation.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: An antenna system, with a loop antenna and a loop current, is provided for transmitting an electromagnetic signal through a medium. The loop antenna has an E field transducer that generates an E field, and an H field transducer that generates an H field. The E and H fields are orthogonal in space and have at least one of a magnitude and phase relationship that is matched to an intrinsic impedance of a medium to generate a propagating wave. In an insulating medium the loop current lags an E field plate voltage by 90° to produce in phase E and H fields. In a conductive medium current is applied to the loop with a 135° phase lag with respect to a voltage across the E field plates. The H field is generated by the current component and leads current by 90°.

Abstract: A wearable article of clothing and the like is configured to be worn by a person underwater or underground; An antenna with at least one loop, is coupled to the wearable item. The antenna provides transmission or receipt of electromagnetic signals and has a size and geometry that maximizes antenna transmission area while minimizing a restriction on movement by the person wearing the wearable article. The antenna carries an alternating current that provides conductive attenuation and has three different field components. Each field component has a different geometric loss when moving a distance r from the antenna. R is a propagating distance from the antenna.

Abstract: An environmental monitoring system including at least one underwater measurement device and a transmitter for transmitting data from the measurement device to an above water station using a magnetically coupled antenna.

Abstract: A multimode wireless communications system that uses the three mechanisms of light, radio and acoustic carriers either in combination or through selection of the most appropriate carrier.

Abstract: A magnetic and/or magneto-electric antenna that has a plurality of conducting loops, two or more of the loops being driven by separate drivers, wherein the loops are positioned side by side in a net-like layout.

Abstract: A bidirectional asymmetric system is provided with a first node and a second node. The first node has a first transmitter that produces a modulated magnetic flux and a first exciter receiver that acts to receive data at the first node. The second node is coupled to the first node with a direct inductive communications downlink and a mutually inductive uplink. The second node includes a receiver that produces a signal induced by the first transmitter at the first node. The second node has a mutually inductive data transmitter that modules an exciter signal produced at the first node by the exciter receiver.

Abstract: A transceiver antenna system comprising at least one solenoid receive antenna and at least one transmitting loop antenna, the at least one solenoid receive antenna being located with its axis in the plane of a transmitting loop antenna and located inside the loop.

Abstract: A wearable article of clothing and the like is configured to be worn by a person underwater or underground; An antenna. with at least one loop, is coupled to the wearable item. The antenna provides transmission or receipt of electromagnetic signals and has a size and geometry that maximizes antenna transmission area while minimizing a restriction on movement by the person wearing the wearable article. The antenna carries an alternating current that provides conductive attenuation and has three different field components. Each field component has a different geometric loss when moving a distance r from the antenna. R is a propagating distance from the antenna.

Abstract: A magnetic and/or magneto-electric antenna is provided that has a plurality of conducting loops. Two or more of the loops are driven by separate drivers.