Abstract: Some embodiments are directed to a cross-domain communication system and method. The system includes a data hub connectable to first domain and to a second domain, the first and second domains being isolated from one another. The data hub may be connected independently to the first domain and to the second domain, such that it is able to receive data from the first domain and transmit data to the second domain. The data hub includes a processor, and optionally a data diode, the processor being adapted to inspect packet data received from the first domain, and to run a set of user-defined rules, such that commands are applied to the packet data in accordance with the rules. When a command applied to packet data received from the first domain it creates packet data transmittable to the second domain in real time, such that the first and second domains communicate indirectly via the data hub.

Abstract: Some embodiments are directed to a drive configuration for a skid-steered vehicle that has a pair of traction motors for rotationally driving opposite outputs of the drive configuration. The traction motors are operatively connected to the outputs via respective gearing arrangements for selectively varying gear reduction between each of the traction motors and the corresponding output. The drive configuration also has a steer differential in a torque connection with the first and second outputs of the drive configuration. The drive configuration additional has a steer motor operatively connected to the steer differential for selectively varying the rotational speed of the first and second outputs in use. Also, the traction and steer motors define a volume in which the gearing arrangements and steering differential are at least partially located.

Abstract: An oil and gas well shaped charge perforator capable of providing an exothermic reaction after detonation is provided, comprising a housing (2), a high explosive (3), and a reactive liner (6) where the high explosive is positioned between the reactive liner and the housing. The reactive liner (6) is produced from a reactive composition which is capable of sustaining an exothermic reaction during the formation of the cutting jet. The composition is a pressed i.e. compacted particulate composition comprising at least two metals, wherein one of the metals is present as spherical particulate, and the other metal is present as a non-spherical particulate. There may also be at least one further metal, which is not capable of an exothermic reaction with the reactive composition, present in an amount greater than 10% w/w of the liner. To aid consolidation a binder may also be added.

Abstract: A radio receiver includes a downconverter for downconverting dual sideband signals such as Binary Offset Carrier (BOC) signals from multiple sources to produce an upper and a lower sideband signal, and chip-matched filters for filtering each of the sideband signals. The output of each filter is provided to a series of separate channels, one for each source, where there are at least Early, Prompt and Late gates. Each gate has a nearest-neighbour sampler and a multiplier for multiplying with an appropriate part of a spreading code, a mixer for removing Doppler or other frequency offsets and an integrator. The invention provides a means for demodulating signals such as BOC modulated satellite navigation signals in an efficient manner by using a single downconverter for the received signals of interest from the multiple sources.

Abstract: A radar system for the detection of drones, including a transmitter, a receiver and a processor, wherein the processor is arranged to process demodulated return signals in a first process using a Doppler frequency filter, and to store locations of any detections therefrom, and to process the demodulated signals in a second process to look for signal returns indicative of a preliminary target having a rotational element at a location, and should a detection be found in the second process, to then attempt to match a location of the preliminary target with returns from the first process, and to provide a confirmed detection if a location of a detection from the first process matches with the location of a detection from the second process. The disclosed subject matter enables improved detection rates for drones, by looking for outputs from both the first and second processes.

Abstract: A wind turbine including a support structure and one or more turbine blades is presented, that incorporates ways for reducing the radar cross section (RCS), wherein the support structure is notionally divided into an upper section in the shadow of the blade sweep area, and a lower section beneath the upper section, wherein the upper section is adapted to have the ways for reducing the RCS, and the lower section does not have the adaptation. The invention makes use of the realisation that the blade masking the tower as it rotates (or the blade being masked by the tower if facing away from a radar), contributes significantly to interference to radar systems, and so localised application of e.g. RAM can give good RCS reduction at a lower cost than treating the whole structure.

Abstract: Some embodiments are directed to a transmission including a plurality of shafts, each carrying a plurality of drive members, the drive members on each shaft arranged to operatively cooperate with those carried by at least one other shaft for transferring load between a torque input and a torque output of the transmission in use, the transmission being configured such that respective resultant gear ratios between the torque input and the torque output can be selected in use from each of a plurality of groups thereof by changing a load path between the torque input and the torque output, wherein each group of selectable resultant gear ratios has a load path feature for transferring load between a pair of the shafts which is common to the selectable resultant gear ratios within that group.

Abstract: Some embodiments are directed to a shaped charge liner including an apex end and a base end and defining a main liner axis that passes through the apex and base ends, the liner being rotationally symmetric about the main liner axis wherein the liner has discrete rotational symmetry about the main liner axis.

Abstract: Some embodiments are directed to a transmission including a plurality of shafts, each carrying a plurality of drive members, the drive members on each shaft arranged to operatively cooperate with those carried by at least one other shaft for transferring load between a torque input and a torque output of the transmission in use, the transmission being configured such that respective resultant gear ratios between the torque input and the torque output can be selected in use from each of a plurality of groups thereof by changing a load path between the torque input and the torque output, wherein each group of selectable resultant gear ratios has a load path feature for transferring load between a pair of the shafts which is common to the selectable resultant gear ratios within that group.

Abstract: A method of tracking a plurality of signals from a single satellite comprises receiving a first signal transmitted by a satellite; receiving at least a second signal transmitted by the same satellite; applying a pre-filtering process to determine the cumulative in-phase and quadrature components of the first, second signals, and optionally any further signals; and applying a filtering process to the cumulated in-phase and quadrature components of the first and at least second signals to determine a range and range rate of the satellite; wherein the filtering process comprises applying a Kalman filter. The method results in a determination of the range and range rate from a single satellite with improved signal to noise ratio. The range and range rate so determined may be used, with data from other satellites, to produce a navigational position. The method may be used with each such satellite used in producing the navigational position.

Abstract: A drone detection radar can include a plurality of antenna systems, each antenna system being arranged to transmit a signal into an associated sector, and to receive signals reflected from targets in the sector, the sectors collectively forming a monitored volume, and wherein a sub-set of the antenna systems are active at any one time, with the active sub-set of antenna systems being arranged to monitor their respective volumes for a duration sufficient to measure Doppler signals associated with slow moving drones, with the radar being arranged to switch to a different sub-set of antenna systems after each duration, such that the whole volume is monitored within a predetermined period. Combining a staring array from an antenna system with a plurality of switched antenna system allows drones to be both detected and tracked, with appropriate selection of the predetermined period.

Abstract: Some embodiments are directed to a drive configuration for a skid steered vehicle includes first and second torque outputs coupled by a differential and in a torque connection with first and second electric motors, the differential being configured to mechanically transfer power across itself; and a mechanical power splitter having a first torque transfer feature in a torque connection with a combustion engine, a second torque transfer feature in a torque connection with a respective additional electric motor and a third torque transfer feature in a torque connection with at least one of the first and second torque outputs of the drive configuration, wherein torque output from the or each the mechanical power splitter in use is dependent on torques generated by the combustion engine and the associated additional electric motor.

Abstract: Some embodiments are directed to a transmission including a plurality of shafts, each carrying a plurality of drive members, the drive members on each shaft arranged to operatively cooperate with those carried by at least one other shaft for transferring load between a torque input and a torque output of the transmission in use, the transmission being configured such that respective resultant gear ratios between the torque input and the torque output can be selected in use from each of a plurality of groups thereof by changing a load path between the torque input and the torque output, wherein each group of selectable resultant gear ratios has a load path feature for transferring load between a pair of the shafts which is common to the selectable resultant gear ratios within that group.

Abstract: The invention relates to devices incorporating thin, lightweight electrochemical cells and their method of manufacture, whereby a thin flexible pouch-type cell (1) comprises at least one pair of overlying electrode layers separated from one another by an intermediate electrolyte layer (13), the cell exterior being defined by first and second laminated sheets (3, 9) sealed together, wherein each laminated sheet (3, 9) has an outermost layer (3a, 9a) forming a respective external face of the cell (1) and a coextensive, innermost, conductive layer (3b, 9b) that acts as a current collector layer (3b, 9b) and which supports an electrode layer (5, 11), although the conductive layer may also itself act as the active electrode layer.

Abstract: A method for the reception of a frequency hopped direct sequence spread spectrum signal includes acquiring the signal by splitting the received signal into a plurality of processing sub-channels, each corresponding to one or more hop frequencies; and within each sub-channel: i) subtracting any sub-carrier frequency from the received signal; ii) filtering the signal from (i) using a chip-matched filter; iii) selecting a sub-set of samples from the filtered signal; iv) correlating the sampled signal from step (iii) with a known reference signal to produce at least one correlator output. The output(s) from each sub-channel are provided to an input of a corresponding one or more common discrete time Fourier transforms (DTFT), and an output therefrom having a peak above a predetermined threshold is selected for further processing in the receiver. The method is a less expensive way of tracking the signal and can demodulate appropriately modulated signals.

Abstract: An oil and gas well shaped charge perforator capable of providing an exothermic reaction after detonation is provided, comprising a housing (2), a high explosive (3), and a reactive liner (6) where the high explosive is positioned between the reactive liner and the housing. The reactive liner (6) is produced from a reactive composition which is capable of sustaining an exothermic reaction during the formation of the cutting jet. The composition is a pressed i.e. compacted particulate composition comprising at least two metals, wherein one of the metals is present as spherical particulate, and the other metal is present as a non-spherical particulate. There may also be at least one further metal, which is not capable of an exothermic reaction with the reactive composition, present in an amount greater than 10% w/w of the liner. To aid consolidation a binder may also be added.

Abstract: A method for mitigating interference in a receiver, where the received signal is transmitted in a fashion having equivalent information content in at least two distinct bands. The method compares mean power per unit bandwidth in suitably normalised sidebands and sets a rejection threshold based upon the measured levels. Bands above the threshold may be rejected from further processing. The bands may include sidebands produced by a modulation process that produces sidebands having the same informational content. The threshold may be set relative to the band having the lowest mean power per unit bandwidth or according to some other function of the bands. Also extends to a signal processor in a receiver, and a receiver. The primary focus of the application is toward the Galileo Public Regulated Service (PRS) Satellite navigation signal.

Abstract: Some embodiments are directed to a method of determining the time of arrival of an incoming satellite signal at a receiver, including receiving an incoming signal, multiplying of the incoming signal by a first real-valued periodic modifying signal to produce a first modified output, correlating the first modified output to obtain a first correlation output, multiplying the incoming signal by a second real-valued periodic modifying signal to produce a second modified output, correlating the second modified output to produce a second correlation output and comparing the first correlation output with the second correlation output.

Abstract: Some embodiments are directed to a gearbox including first and second rotational members, the first rotational member having a shaft portion extending away from the gearbox, the first rotational member carrying one or more projections, the second rotational member carrying one or more complementary projections, the projections carried by the first rotational member being configured to be drivingly engaged with the complementary projections carried by the second rotational member to transmit torque in a first torque connection but not in a torque connection that is opposed to the first torque connection. The gearbox further includes a one way clutch adapted such that the first and second rotational members can be drivingly engaged to transmit torque in a second torque connection, wherein the second torque connection is opposed to the first torque connection.

Abstract: Some embodiments are directed to a drive configuration for a skid-steered vehicle that has a pair of traction motors for rotationally driving opposite outputs of the drive configuration. The traction motors are operatively connected to the outputs via respective gearing arrangements for selectively varying gear reduction between each of the traction motors and the corresponding output. The drive configuration also has a steer differential in a torque connection with the first and second outputs of the drive configuration. The drive configuration additional has a steer motor operatively connected to the steer differential for selectively varying the rotational speed of the first and second outputs in use. Also, the traction and steer motors define a volume in which the gearing arrangements and steering differential are at least partially located.