Abstract: Disclosed is a method of encrypting a data signal for providing to an input of a radio frequency transmitter, such as modulated baseband signals in the physical layer for wireless transmission. The method comprises receiving the data signal comprising one or more first frequency components with a first phase profile in a frequency band of interest; applying a dispersive encrypting signal filter to the data signal to generate an encrypted data signal comprising the one or more frequency components with a second phase profile, wherein the second phase profile is different to the first phase profile. Decryption is achieved by applying a decrypting filter to the encrypted data signal to substantially reverse the effect of the encrypting filter and recover the first phase profile.

Abstract: A method for determining amplitude and phase correction coefficients for one or more signal processing paths across a frequency band of interest is provided. The method comprises transforming an input test signal from the time domain to the frequency domain to obtain an input magnitude spectrum and an input phase spectrum for the/each signal processing path. It further comprises transforming an/each respective output test signal from the time domain to the frequency domain to obtain an output magnitude spectrum and an output phase spectrum for the/each signal processing path. It also comprises comparing the/each input magnitude spectrum with its respective output magnitude spectrum to determine an amplitude correction coefficient for the/each signal processing path and/or comparing the/each input phase spectrum with its respective output phase spectrum, to determine a phase correction coefficient for the or each signal processing path.

Abstract: Disclosed is a method of encrypting a data signal for providing to an input of a radio frequency transmitter, such as modulated baseband signals in the physical layer for wireless transmission. The method comprises receiving the data signal comprising one or more first frequency components with a first phase profile in a frequency band of interest; applying a dispersive encrypting signal filter to the data signal to generate an encrypted data signal comprising the one or more frequency components with a second phase profile, wherein the second phase profile is different to the first phase profile. Decryption is achieved by applying a decrypting filter to the encrypted data signal to substantially reverse the effect of the encrypting filter and recover the first phase profile.

Abstract: Disclosed is a method of encrypting a data signal for providing to an input of a radio frequency transmitter, such as modulated baseband signals in the physical layer for wireless transmission. The method comprises receiving the data signal comprising one or more first frequency components with a first phase profile in a frequency band of interest; applying a dispersive encrypting signal filter to the data signal to generate an encrypted data signal comprising the one or more frequency components with a second phase profile, wherein the second phase profile is different to the first phase profile. Decryption is achieved by applying a decrypting filter to the encrypted data signal to substantially reverse the effect of the encrypting filter and recover the first phase profile.

Abstract: Disclosed is a method of reducing the Instantaneous to Average Power Ratio, IAR, of a transmitter system, comprising the steps of: receiving an input digital signal comprising a plurality of samples; extracting magnitude information for each of the plurality of samples; selecting a plurality of samples whose magnitude exceeds a predefined threshold; sorting, by magnitude, the selected plurality of samples; selecting from the sorted plurality of samples, only those samples having a spacing more than a first pre-defined spacing and filtering those samples, using an FIR filter; subtracting the output of the FIR filter from a delayed version of the input digital signal to produce an output signal.

Abstract: Disclosed is a method of reducing the Instantaneous to Average Power Ratio, IAR, of a transmitter system, comprising the steps of: receiving an input digital signal comprising a plurality of samples; extracting magnitude information for each of the plurality of samples; selecting a plurality of samples whose magnitude exceeds a predefined threshold; sorting, by magnitude, the selected plurality of samples; selecting from the sorted plurality of samples, only those samples having a spacing more than a first pre-defined spacing and filtering those samples, using an FIR filter; subtracting the output of the FIR filter from a delayed version of the input digital signal to produce an output signal.

Abstract: A method for determining amplitude and phase correction coefficients for one or more signal processing paths across a frequency band of interest is provided. The method comprises transforming an input test signal from the time domain to the frequency domain to obtain an input magnitude spectrum and an input phase spectrum for the/each signal processing path. It further comprises transforming an/each respective output test signal from the time domain to the frequency domain to obtain an output magnitude spectrum and an output phase spectrum for the/each signal processing path. It also comprises comparing the/each input magnitude spectrum with its respective output magnitude spectrum to determine an amplitude correction coefficient for the/each signal processing path and/or comparing the/each input phase spectrum with its respective output phase spectrum, to determine a phase correction coefficient for the or each signal processing path.

Abstract: A method for utilising an array of independently controllable dielectric lenses for radio signal to allow a single antenna to be focussed on one location with a highly directive beam or on more than one location thus enable radio links to be formed with multiple locations. Within the array, each lens will consist of a shaped piece of dielectric material that can be independently, or in groups, pointed in such a direction as to change the direction of the radio signals passing through the lens. The lens will have a shape equivalent to a converging lens which may be a convex shape. Other forms of converging lens may be implemented save space and material. The antenna will have a low gain, wide area of reception and may be implemented as a planar metal antenna or as a group of planar antennas in an array. This invention provides a lightweight system for providing high gain antenna performance without the need for a complex antenna array system or the need for multiple transceiver electronics.

Abstract: The invention provides a method and system for managing data connectivity links for a plurality of aircraft in a network wherein at least one aircraft is a non-cooperative aircraft, said network comprising a plurality of sub-mesh regions, each sub-mesh having a plurality of nodes, wherein at least one node is representative of an aircraft, and a control sub-mesh node configured to maintain a plurality of data links with the plurality of aircraft in the sub-mesh region based on a generated real-time map of data connections for the sub-mesh region; and a master control node configured to control each control sub-mesh node of each sub-mesh region.

Abstract: The invention is for a system and method of constructing an array of fixed antennas to provide coverage for radio communications to multiple mobile aerial vehicles from a terrestrial location. In one embodiment there is provided antenna system providing radio communications to a plurality or moving aerial vehicles, said system comprising an array of fixed antennas; at least one or a plurality of transceivers selectively connected to the array of fixed antennas; and a control unit configured to switch individual antennas from said array to connect with at least one transceiver. The control unit is configured with a switch matrix to control the connections from the antennas to the plurality of transceivers to implement a desired communications protocol, and the system is further configurable to supply exclusion policies to the control unit which identify which antennas are not to be connected to the switch matrix.

Abstract: The invention provides a system and method of providing service coverage for the provision of data services to a target aircraft comprising the step of configuring one or more other aircraft in an area at a specific time such that the data services can be provided via a radio or communication link to the target aircraft via the one or more other aircraft; and predicting a data services requirement in an area and configuring a pattern of communication links with the one or more other aircraft and the target aircraft to maintain the predicted data services.

Abstract: The invention provides a method and system for managing data connectivity links for a plurality of aircraft in a network wherein at least one aircraft is a non-cooperative aircraft, said network comprising a plurality of sub-mesh regions, each sub-mesh having a plurality of nodes, wherein at least one node is representative of an aircraft, and a control sub-mesh node configured to maintain a plurality of data links with the plurality of aircraft in the sub-mesh region based on a generated real-time map of data connections for the sub-mesh region; and a master control node configured to control each control sub-mesh node of each sub-mesh region.

Abstract: The invention provides a system and method of providing service coverage for the provision of data services to a target aircraft comprising the step of configuring one or more other aircraft in an area at a specific time such that the data services can be provided via a radio or communication link to the target aircraft via the one or more other aircraft; and predicting a data services requirement in an area and configuring a pattern of communication links with the one or more other aircraft and the target aircraft to maintain the predicted data services.

Abstract: An authorisation management and flight compliance system for a plurality of Unmanned Aerial Vehicles (UAV) operating in a region, said system configured to assess a flight command request for a UAV submitted by an authorised controller for approval, the assessment based on constraints for the flight and a level of authority assigned to the controller; and cryptographically sign an approved command request and return the signed command request to the controller for sending to the UAV.

Abstract: The invention is for a system and method of constructing an array of fixed antennas to provide coverage for radio communications to multiple mobile aerial vehicles from a terrestrial location. In one embodiment there is provided antenna system providing radio communications to a plurality or moving aerial vehicles, said system comprising an array of fixed antennas; at least one or a plurality of transceivers selectively connected to the array of fixed antennas; and a control unit configured to switch individual antennas from said array to connect with at least one transceiver. The control unit is configured with a switch matrix to control the connections from the antennas to the plurality of transceivers to implement a desired communications protocol, and the system is further configurable to supply exclusion policies to the control unit which identify which antennas are not to be connected to the switch matrix.

Abstract: A method for utilising an array of independently controllable dielectric lenses for radio signal to allow a single antenna to be focussed on one location with a highly directive beam or on more than one location thus enable radio links to be formed with multiple locations. Within the array, each lens will consist of a shaped piece of dielectric material that can be independently, or in groups, pointed in such a direction as to change the direction of the radio signals passing through the lens. The lens will have a shape equivalent to a converging lens which may be a convex shape. Other forms of converging lens may be implemented save space and material. The antenna will have a low gain, wide area of reception and may be implemented as a planar metal antenna or as a group of planar antennas in an array. This invention provides a lightweight system for providing high gain antenna performance without the need for a complex antenna array system or the need for multiple transceiver electronics.

Abstract: An antenna array comprises a surface comprising a replicated pattern of conductive tracks, the tracks defining a plurality of ports. A plurality of antennae are located at ports distributed about the surface. A plurality of radiative transceivers are electrically connected to a respective antenna. A plurality of reference transceivers are electrically connected to a non-radiative impedance located at a respective port so that each reference transceiver is surrounded by a group of antennae and electrically coupled to the group of antennae by the tracks. At least one antenna from at least one group of antennae belongs to one other group of antennae. Calibration circuitry includes a controller associated with each reference transceiver, each controller being arranged to transmit a calibration signal through an associated reference transceiver and to receive and store a received calibration signal from a selected transceiver for the group of antennae coupled to the reference transceiver.

Abstract: A switched mode class-S power amplifier comprises a sigma-delta modulator with a digital input, a power switch connected to the output of the sigma-delta modulator providing the power amplifier output, and a feedback mechanism. The sigma-delta modulator has a high-pass transfer function and uses an offset switching frequency to remove an unwanted image over half of the switching frequency. The amplifier may have a filter to remove unwanted fold-over image. There may be at least two modulators arranged in parallel, and there may be a complex filter for constructively combining the modulator outputs.

Abstract: An antenna array comprises a surface comprising a replicated pattern of conductive tracks, the tracks defining a plurality of ports. A plurality of antennae are located at ports distributed about the surface. A plurality of radiative transceivers are electrically connected to a respective antenna. A plurality of reference transceivers are electrically connected to a non-radiative impedance located at a respective port so that each reference transceiver is surrounded by a group of antennae and electrically coupled to the group of antennae by the tracks. At least one antenna from at least one group of antennae belongs to one other group of antennae. Calibration circuitry includes a controller associated with each reference transceiver, each controller being arranged to transmit a calibration signal through an associated reference transceiver and to receive and store a received calibration signal from a selected transceiver for the group of antennae coupled to the reference transceiver.

Abstract: Indane dimer compounds and their pharmaceutical use particularly to achieve smooth muscle relaxing activity and/or mast cell stabilizing activity and/or anti-inflammatory activity are described.