Abstract: An analogue modem circuit and carrier recovery method are disclosed for use between an RF receiver and a digital modem circuit configured for receiving a baseband RF input signal, and including an up-converter with frequency supplied by an up-converter voltage controlled oscillator, VCO; a down-converter with frequency supplied by a down-converter VCO; a Costas loop sub-module; and baseband outputs from the down-converter to a digital modem circuit. The up-converter feeds the down-converter, and the Costas loop module performs Costas loop functionality on the output of the down-converter to control the up-converter VCO frequency output to thereby control modification of rotation of symbols of the baseband signal.

Abstract: A point-to-point radio frequency (RF) communication system having one or more communication units coupled to respective television cameras and displays; and a further communication unit; wherein the units transmit video data to the further communication unit at frequencies greater than or equal to 50 GHz and at data rates greater than or equal to 1 gigabit/second; and the units receive video data transmitted by the further communication unit at frequencies greater than or equal to 50 GHz and at data rates 250 megabits/second. The units can each include an antenna with a waveguide diplexer and an RF transceiver circuit board having sufficient transmit/receive isolation for the transmitting and receiving to take place point-to-point at distances greater than or equal to 1 km.

Abstract: Apparatus for providing antenna diversity for a radio transmitter/receiver (TR) comprising measuring means for measuring relative received signal strengths in a plurality of antennas in a selectable frequency range, means for selecting the selectable frequency range according to a transmission frequency of the TR, and connecting means for connecting the antenna having the greatest received signal strength to the TR. The apparatus may be combined with a plurality of antennas to form a diversity antenna system, for example for use with a personal radio. The antennas may then be disposed spaced apart on the user's body e.g. by being incorporated into a garment.

Abstract: A bias controller and a method for controlling the bias of an electro-optic modulator are provided. In the method, for a received indication of modulator temperature, steps are provided for accessing a look-up table to determine a corresponding value of bias voltage, for a required bias point, to apply to the modulator. If no such value is stored, additional steps are provided to generate a pilot tone for input to the modulator and to recognize, from the signal content of a modulated optical signal output by the modulator, operation of the modulator at the required bias point, adjusting the value of bias voltage being applied to the modulator as required. When operation at the required bias point is recognized, the respective value of bias voltage for that modulator temperature is stored in the look-up table. The same method is provided to configure a bias controller in respect of a given modulator, if necessary ab initio.

Abstract: A bias controller for an optical modulator. The modulator includes a bias electrode that is operable when appropriately biased by an applied bias voltage to configure the modulator to operate at quadrature, and the bias controller includes: a generating arrangement for generating power signals indicative of the optical output power of the modulator; and a processor operably connected to the generating arrangement and said bias electrode and arranged to receive said power signals from said generating arrangement and to control the bias voltage applied to said bias electrode.

Abstract: A feeding mechanism for animals, particularly pets, comprises a scanner, microchip and means for regulation and provision of food. An animal identification means scans animal identification implants for an identification signal indicative of an animal. When an authorised animal is identified a storage hopper is activated to dispense a predetermined amount of animal feed into a bowl for the animal, when an unauthorised animal is detected close to the feed or the bowl, a repellent, such as a puff of gas, squirt of water, loud noise or other sudden stimulus or shock is generated, so as to frighten off the unauthorised (intruder) animal. In an alternative embodiment the invention also includes an exercise device, which has a projector arranged to shine an image at random over a given area. A sensing means determines how effective an animal is at the device and a score calculated. Upon reaching a given score the animal is rewarded with a treat, which may be food.

Abstract: A feeding mechanism for animals, particularly pets, comprises a scanner, microchip and means for regulation and provision of food. An animal identification means scans animal identification implants for an identification signal indicative of an animal. When an authorised animal is identified a storage hopper is activated to dispense a predetermined amount of animal feed into a bowl for the animal, when an unauthorised animal is detected close to the feed or the bowl, a repellent, such as a puff of gas, squirt of water, loud noise or other sudden stimulus or shock is generated, so as to frighten off the unauthorised (intruder) animal. In an alternative embodiment the invention also includes an exercise device, which has a projector arranged to shine an image at random over a given area. A sensing means determines how effective an animal is at the device and a score calculated. Upon reaching a given score the animal is rewarded with a treat, which may be food.

Abstract: A system for identifying an animal, comprising an identification tag/transponder device (4) surgically implanted into tissue of said animal and a scanning unit (5), wherein as said animal passes in the vicinity of a scanning unit, the system causes the identification device to send a signal to a receiving portion of said scanning unit, and including means to process said signal, and comparison means so as to identify the animal from said signal. The system is of particular benefit to veterinary surgeries in assisting their smooth operation.

Abstract: The present invention relates to a bias controller for a dual output electro-optic modulator and a method for controlling the bias of a dual output electro-optic modulator. The invention further comprises an optical commutator switch with a plurality of dual-output electro-optic modulators interconnected in a tiered arrangement, and control means for deriving measurements of optical power from each of the modulators. The optical commutator is further used for determining respective bias control signals to achieve and maintain operation of the modulators substantially at their quadrature bias points, and further for generating said respective bias control signals for applying them to the respective modulators.

Abstract: This invention relates to optical delay lines, particularly to modifying an optical signal passing through an optical delay line. A method of applying a Doppler shift to an optical signal as it passes through an optical delay line is provided, the method comprising the step of progressively altering a property of the optical delay line during passage of the optical signal therethrough such that the time taken for the optical signal to pass therethrough is progressively lengthened or progressively shortened for successive portions of the optical signal. In addition, an optical delay line is provided that may be used in accordance with the above method.

Abstract: A bias controller and a method for controlling the bias of an electro-optic modulator are provided. In the method, for a received indication of modulator temperature, steps are provided for accessing a look-up table to determine a corresponding value of bias voltage, for a required bias point, to apply to the modulator. If no such value is stored, additional steps are provided to generate a pilot tone for input to the modulator and to recognize, from the signal content of a modulated optical signal output by the modulator, operation of the modulator at the required bias point, adjusting the value of bias voltage being applied to the modulator as required. When operation at the required bias point is recognized, the respective value of bias voltage for that modulator temperature is stored in the look-up table. The same method is provided to configure a bias controller in respect of a given modulator, if necessary ab initio.

Abstract: The present invention relates to a bias controller for a dual output electro-optic modulator and a method for controlling the bias of a dual output electro-optic modulator. The invention further comprises an optical commutator switch with a plurality of dual-output electro-optic modulators interconnected in a tiered arrangement, and control means for deriving measurements of optical power from each of the modulators. The optical commutator is further used for determining respective bias control signals to achieve and maintain operation of the modulators substantially at their quadrature bias points, and further for generating said respective bias control signals for applying them to the respective modulators.

Abstract: The invention relates to novel NO donors which are targeted to the mitochondria. The NO donor compounds of the invention allow NO to be selectively provided to the mitochondria.

Abstract: A process and apparatus for detecting underwater objects comprises an elongate array of ultrasound transmitter elements mounted substantially vertically and forward facing on the bow of the ship from which is transmitted a sequence of ultrasound wave pulses, with each pulse having a frequency and vertical beam angle which are different to the frequency and vertical beam angle of the preceding pulse in the sequence, the frequency being characteristic of the vertical beam angle and the vertical beam angle being controlled by using time delays between different transmitter elements, and an elongate array of ultrasound receiver elements mounted substantially horizontally on the bow of said ship with the receiver elements forward facing which receive any ultrasound waves reflected from objects in front of the ship, the output from the receiver elements being steered horizontally using time delays between different receiver element outputs and for each horizontal position of the beam of outputs, the outputs from th

Abstract: A bias controller for an optical modulator. The modulator includes a bias electrode that is operable when appropriately biased by an applied bias voltage to configure the modulator to operate at quadrature, and the bias controller includes: a generating arrangement for generating power signals indicative of the optical output power of the modulator; and a processor operably connected to the generating arrangement and said bias electrode and arranged to receive said power signals from said generating arrangement and to control the bias voltage applied to said bias electrode.

Abstract: The invention relates to novel NO donors which are targeted to the mitochondria. The NO donor compounds of the invention allow NO to be selectively provided to the mitochondria.

Abstract: The methods of preparing quinols and quinones typified by mitoquinol and mitoquinone where a compound typified by idebenone is reacted with Ph3PHX and Ph3P, where X is a halogen atom.