Abstract: A cavity system that tends to increase the thickness (28) of the shear layer FIG. 1 (22), comprising: a cavity (2) and a plurality of rods (4), for example between two and six rods; the rods (4) are positioned in the proximity of a leading edge (14) of the cavity (2) and extending across at least a part of a width of the cavity (2) in a perpendicular or oblique angle to the actual or intended flow direction (6). One or more of the rods (4) may be positioned further along the flow direction (6) compared to one or more of the other rods (4), for example to provide a zig-zag pattern of rod positions. One or more flow alteration elements (34, 38), for example channels (34) passing through the rods (4) and/or protrusions (38) extending from the rods (4), may be provided on one or more of the rods (4).

Abstract: There is disclosed a directional multi-band antenna comprising a substrate structure, a plurality of RF units arranged at the substrate structure to provide an RF phased array, the RF phased array having an angular scan range, an array of optical units arranged at the substrate structure and interspersed amongst the RF units, an array of optical lensing devices supported over the substrate structure, the array of optical lensing devices being substantially RF transmissive and being arranged to correspond with the arrangement of the optical units, such that each optical unit may communicate light signals with an associated optical lensing device so as to communicate light signals along an optical axis within the angular scan range of the RF phased array

Abstract: A vehicle (2) comprising a vehicle part (4), the vehicle part (4) comprising: an electrically conductive core (6); a non-electrically conductive outer skin (8) made of a radar-absorbent material which surrounds, at least to some extent, the core (6) such that the core (6) is not visible from outside the vehicle (2); and one or more electrically conductive members (10) electrically connected to the core (6); each of the one or more members (10) is a tapered member having a relatively large cross sectional area where that member (10) is electrically connected to the core (6), and tapers from its end that is connected to the core (6) to a point; and the point of each member (10) is located at an outer surface of the external skin (8) such that the point of each of the members (10) is exposed.

Abstract: Apparatus and method for providing the apparatus, the apparatus including: a duct; and a non-return valve; wherein the duct has a first portion and a second portion; the first portion has a first end and a second end; the first end is open to a fluid (e.g. air); the second end is connected to the second portion such that fluid is permitted to flow between the first portion and the second portion; the non-return valve is positioned at or proximate to the second end; and the non-return valve is arranged such that, upon application of a suction force to the first portion at the first end, fluid flows into the first portion via the non-return valve from outside the duct, and through the first portion from the second end to the first end.

Abstract: A detector for detecting ionizing radiation comprises a scintillator 10 selected to emit light in response to incidence thereon of radiation to be detected, at least one detector 16 for detecting said emitted light, and at least one optical waveguide 12 for transmitting said emitted light to said detector 16. The optical waveguide typically comprises a flexible solid or hollow fiber that can be incorporated into a flexible mat or into a fiber-reinforced structure, so that the detector is integrated therewith.

Abstract: An apparatus and a method are disclosed for tracking a plurality of targets (e.g. land-based vehicles). The method can include: for a first time-step, estimating a state of each respective target; at a second time-step, measuring values for a state of each target; for the second time-step, estimating a state of each target using the estimated target states for the first time-step; updating the estimated target states for the second time-step by performing a Joint Probabilistic Data Association process using the measured values; and performing an identity management process to estimate a probability that a particular state measurement corresponds to a particular.

Abstract: According to the invention there is provided an arrangement of protective material for dissipating the kinetic energy of a moving object including one or more layers of fibrous armour material encased within a sealed encasement, in which the sealed encasement is formed from a textile armour material which is impregnated with a polymeric substance.

Abstract: An inceptor apparatus and method for operating a machine, the operation of the machine providing an output from at least one inertial sensor. The apparatus comprises a stick member having a base portion, and a grip portion extending from the base portion in only one direction. The apparatus further comprises at least one sensor for generating actual stick member position data, and a control unit configured to receive an inertial force signal from the or each inertial sensor and the actual stick member position data. The control unit is operable generate a first stick member position compensation signal in dependence upon the inertial force signal and actual stick member position data.

Abstract: There is disclosed an integrated lighting and network-interface device comprising a housing defining an aperture, a lens supported at the aperture for allowing light and 55-65 GHz radiation to pass therethrough, a light source, a transceiver module having an antenna unit, the transceiver module being adapted for connection to an optic fibre port, and being for operation at at least one centre frequency between 55 GHz and 65 GHz, wherein the light source and the antenna unit are disposed in the housing and arranged to radiate through the lens.

Abstract: The invention relates to ferrite compositions, particularly ferrite coated substrates and more particularly fibre plys coated with ferrites in fibre reinforced polymer composites (FRPC), and composites with a plurality of functionalised fibre layers The invention provides a magnetic ferrite composition for coating a substrate, said composition comprising a resin, and dispersed therein ferrite particulates, wherein said ferrite particulates have an average longest dimension of less than 500 nm. The composition may be used to provide a ferrite composite structure comprising at least one fibre ply, with at least one layer of a magnetic ferrite composition deposed thereon, wherein said ply is substantially encapsulated in a binder matrix to form a fibre reinforced polymer composite.

Abstract: An antenna comprising two or more substantially identical antenna sub-arrays (3A, 3B) each comprising a plurality of separate antenna radiating elements (6A, 6B) connected to a common radio frequency (RF) signal input/output port (4A, 4B). The separate antenna elements are connected to the RF signal input/output port via respective RF signal power dividers (8A, 8B). A variance in values of the power splitting ratio, and/or of the input RF signal reflectivity, and/or of the phase balance of corresponding signal power dividers of the two or more antenna sub-arrays is sufficient to provide a cancellation ratio exceeding 40 dB. Alternatively, the separate antenna elements are connected to the RF signal input/output port via respective transmission paths (7A, 7B) and a variance in values of the transmission path lengths of corresponding signal transmission paths of the two or more antenna sub-arrays is sufficient to provide a cancellation ratio exceeding 40 dB.

Abstract: A map display device 200 stores a map image dataset 211 with image pixels including a plurality of static-type pixels 410 each having only one color value 412, and a plurality of dynamic-type pixels 420 each having a predefined set of color values 422-426, and a function definition field 428 which defines a function to select between said color values 422-426. A graphics processor 220 processes one tile 401 of map image data by, for each of the dynamic type pixels 420, retrieving the function identified by the function definition field 428, applying a current time value to the function, and selecting one of the predefined set of color values 422-426 according to a result of the function. An output unit 230 outputs the map image frame as a raster image containing one pixel color value at each of the pixels for display on a display screen 240.

Abstract: According to the invention there is provided a dipole antenna array including at least one dipole antenna sub-array, wherein the dipole antenna sub-array includes a plurality of co-planar antenna units, each antenna unit including a pair of dipole radiating elements and a balun having an output line for providing output electrical signals to the pair of dipole radiating elements.

Abstract: A data transfer system includes a set of switch and/or router devices (104B, 104E, 104F), each said device in the set being a layer 1, 2 and/or 3 device of OSI seven-layer model and being configured, in use, to transfer data, directly or indirectly, between a plurality of computing devices (102A, 102B). Each said switch or router device in the set is configured to provide a virtual partition (VP), wherein only data designated as virtual partition data is transferrable to another said device in the set via the virtual partition.

Abstract: A method of high-integrity data transmission including transmitting nominally-identical data via first and second channels, inverting the logic of the data in the second channel receiving the data via a respective data handling device for each channel, inverting the logic of data outputted by one of the data-handling devices and comparing the so-inverted data with data outputted by the other data handling device. The invention is relevant to the avoidance of common-mode failures in aircraft, other vehicles and plant employing high-integrity data systems.

Abstract: The invention relates to methods of bonding and a conductively bonded joint, provided by high loadings of conductively coated nano scale particulate fillers in a conductive adhesive in combination with a conductive intermediary structure, more particularly to a lightning strike resilient bonded joint between fibre reinforced polymer composites. A method of joining a first fibre reinforced polymer composite surface and a second fibre reinforced polymer composite surface, comprising the steps of providing a conductive intermediary structure between said first and second surfaces, filling the void between said surfaces and enveloping said intermediary structure with a conductive adhesive, curing the conductive adhesive to form a bonded first and second surface. A conductive adhesive comprising a curable binder and a high aspect ratio nanoscale carbon particulate filler present in the range of from 0.1 to 40% wt, wherein said particulate filler comprises a metal coating.

Abstract: A diffraction grating 1 includes a surface 12 having grooves 14 therein, each groove 14 providing a diffracting surface for light incident upon the diffracting surface. The grooves 14 are separated from each other by lands 20 upon the surface 12. The lands 20 are of predetermined varying width, whereby the diffractive efficiency of the grating 1 varies across the extent of the grating 1.

Abstract: There is disclosed a directional multi-band antenna comprising: a primary reflector, at least one secondary reflector, a multi-layer dielectric layer selectively reflective or transmissive of incident radiation according to wavelength, the layer being provided at the surface of either the primary or the secondary reflector, an RF unit comprising a collocated sensor and transmitter, an Optical unit comprising a collocated sensor and transmitter, arranged such that the primary reflector is for passing signals between the secondary reflector and the environment, the secondary reflector is firstly for passing signals between the primary reflector and the RF unit, and secondly for passing signals between the primary reflector and the Optical unit and arranged such that the antenna is operable to transmit or receive, RF or Optical signals, along a common beam axis.

Abstract: EM field absorbing compositions, particularly lightweight magnetic and carbon loaded compositions. The composition finds particular use as a radar absorbing coating for structures. There are further provided coated surfaces comprising the composition, methods of absorbing EM radiation, and methods of use of such a composition, such that a surface coated in the composition is capable of absorbing EM radiation. An electromagnetic radiation absorbing composition comprising an admixture of carbon nanotubes present in the range of from 0.1 to 10 v/v % dried, magnetic particulates with an average longest dimension of at least 1 micron, present in the range of from 1 to 60% v/v dried, in a non-conductive binder; preferably the iron particulates are present in the range of from 15-30% v/v.

Abstract: There is disclosed A directional multi-band antenna, the antenna comprising: an optical unit comprising an optical sensor; an RF unit comprising an RF sensor; a substantially planar optical lens, the optical lens comprising surface relief elements for beam forming, the lens being arranged to focus optical signal beams, incident along a first optical axis, onto the optical sensor, the optical lens being substantially transparent to RF signals, an RF beam forming device arranged to receive RF signals incident along the first optical axis and focus such RF signals onto the RF sensor.