Abstract: A focal plane detector for imaging objects within a scene and having integral processing means for detecting edges of objects within the scene. The focal plane detector comprises a plurality of detector elements arranged to measure the intensity of the electromagnetic radiation incident thereon and processing means integral to the focal plane detector for combining the intensity measurements so as to indicate the difference in the intensity of the electromagnetic radiation. The focal plane detector is arranged such that the output from the focal plane detector corresponds to edges of objects within the scene. The focal plane detector may be arranged to be sensitive to infrared radiation.

Abstract: Apparatus for detecting failure of a protective barrier between a first object and a second object is provided. The apparatus includes a transmitter assembly for transmitting an alternating electrical signal through the first object and a receiver assembly, wherein the receiver assembly is configured to receive the alternating electrical signal through the second object upon breach of the protective barrier. In a preferred embodiment, the first object is a patient undergoing surgery and/or medical treatment, the second object is a healthcare worker such as a surgeon and the protective barrier is a glove such as a surgical glove. The transmitter and/or receiver assemblies typically include transmitter or receiver electronics and signal connections, and optionally, the electronics and connections can together form integral transmitter and/or receiver assemblies. A return path can be provided for the transmitted signal.

Abstract: A device for attenuating electromagnetic radiation in a desired transmission frequency band. The device includes a generally planar substrate, and a resistive pattern arranged on the substrate adapted to reflect a proportion of incident radiation in the transmission band. The resistive pattern may be screen printed using carbon based ink. This provides a simple, cheap and easy to fabricate device which can quickly and easily be affixed to the exterior of an antenna or antenna housing to attenuate the power of radiation in the transmission band, resulting in reduced range or sensitivity.

Abstract: A method and system for locating objects in a region having a high degree of multipath susceptibility comprises a plurality of transducers, each being a transmit or receive antenna, and being arranged about the region in known locations, to form a bistatic or multistatic radar, with some embodiments being MIMO systems. Signals transmitted by the transmit antenna(s) are received at each receive antenna and processed to form a set of channel impulse responses, or power delay profiles, representative of the region at a given time. A second set is formed at a different time, and the difference between the two sets is calculated, the difference containing information on movement within the region. The difference may be processed to localise the moving object(s) by graphical means, e.g.

Abstract: An improved millimeter wave illumination system includes at least one primary source of millimeter wave radiation, a reflecting surface and a baffle comprising a plurality of exit apertures arranged such that at least some of the radiation from the source is reflected from the reflective surface before proceeding to the baffle, characterized in that means are incorporated for generating a plurality of radiation field states within a pre-determined time interval. The baffle, source and reflector are preferably packaged into a container with the exit apertures providing an illumination output. The generation of the plurality of radiation field states provides an illumination at the illuminator output that is less spatially variable when integrated over the pre-determined time interval.

Abstract: Sorting apparatus comprising conveying means for conveying input objects into to the apparatus, extraction means for extracting from the conveying means input objects identified as belonging to a particular object-class processing means arranged to received input data corresponding at least to the portions across the conveying means of said identified input objects and to output control signals corresponding to the input data to the extraction means to effect extraction of said identified input objects, where the extraction means comprises an array of nozzles extending in a direction (z) across the conveying means, each of which is independently operable under control of the processing means to produce an air jet in a generally upward direction (y), and is arranged to activate sub-groups of nozzles corresponding to, and in response to, said control signals, characterised in that the conveying means has a partially open surface arranged to convey input objects over the array of nozzles, in that the array of no

Abstract: A head mounted data storage device comprising an audio receiver for receiving audio signals, a solid state memory for storing received signals, and a power source for providing power to said device. The unit is self contained and adapted to be mounted about the head of a user, typically on a headset or integrated within the shell of a helmet.

Abstract: A method of blind signal separation of convolutively mixed signals comprises firstly processing signals to produce second order independence. In a second step, and together with ranges of signal delay and rotation parameters, the resulting processed signals are used to determine delay and rotation parameters. These parameters implement at least one elementary paraunitary matrix and transform the processed signals into output signals with improvement in independence to at least a predominant part of a maximum extent obtainable over the parameter ranges. The output signals then become the next processed signals and the second step is iterated until independence ceases to be improved significantly. The latest output signals are then unmixed signals.

Abstract: A drive configuration for a skid steered vehicle comprises a pair of electric motors for propulsion of the vehicle, one each coupled to drive a respective track on a respective side of the vehicle, and one or more electric steer motors coupled through a differential gear mechanism to impose a speed difference between the tracks. An associated control system controls the current to each motor so that substantial contributions to the differential torque to turn the vehicle are made both by the steer motors and by the propulsion motors, in variable proportions preferably as a function of the vehicle speed.

Abstract: A semiconductor device comprising a plurality of regions of semiconductor material forming a junction at an interface there-between, the junction including a depletion region having a width which varies spatially in at least one direction along the depletion region. Without limitation, the spatial variation in depletion region width is provided by ionised dopants having a concentration which varies spatially along said at least one direction. Alternatively, or in addition, the spatial variation in depletion region width is achieved by varying the thickness of the region(s) of semiconductor spatially along said at least one direction, for example by creating a plurality of cells within said region(s) devoid of said semiconductor material. A method of fabricating a semiconductor device comprising the step of varying the width of the depletion region spatially there-within in at least one direction along the depletion region.

Abstract: An eddy current sensor for use as a dynamic proximity sensor, particularly for monitoring of blade tip timing and clearance in turbomachinery, has a common coil for use in both generating a magnetic field in a proximate region and detecting the effect of eddy currents generated by said field in electrically conductive objects passing through that region. The coil is wound on a rectangular or other elongate former so that the coil is itself elongate in section. This can improve the resolution of the device when used for sensing the passage of objects of elongate section (such as a turbine blade tip when the sensor coil is oriented with its shorter cross-sectional dimension aligned with the shorter cross-sectional dimension of the respective object. Also described is a method of processing a signal wave form from such devices to derive ‘trigger’ points for blade tip timing.

Abstract: A method for providing correction values for phase based measurements. Where averaging techniques are employed for exploiting redundancy in multiple measurements, by constraining the phase ambiguity in a correction value to be an integer multiple of the carrier wavelength, carrier phase based measurements can be used.

Abstract: A self opening hinge comprises a tubular member with a set of circumferentially spaced blades extending longitudinally between opposite end portions. It can be folded by bending the blades to bring the end portions together and when released will naturally return to the straight condition under the spring action of the blades. The blade which will be located on the inside of the fold when the member is in its folded condition is configured with a convex circumferential curvature as viewed from the axis of the member when in its unfolded condition, namely reversed in curvature as compared with the other blades. In this way the stress on the inside blade when the member is folded is reduced as compared with a conventional hinge where all the blades follow a circular tube profile and are concave as viewed from the central axis.

Abstract: A substrate including a surface on which is provided a modifying layer which is incomplete and has a distribution such as to provide a plurality of islands of said material and/or islands of substrate surface whereby the surface exhibits a modified electrical and/or magnetic property.

Abstract: Integration of ionospheric models in over the horizon radars (OTHR) is achieved with very little or substantially no change to existing coordinate registration systems or software by specifying a virtual transponder at a target location and generating a signal which appears to have emanated from a transponder at that location. A return path to said virtual transponder is ray-traced through the ionospheric model to produce propagation parameters; and an appropriately delayed virtual transponder signal is inserted into the receiver. The result produced at the receiver is used to perform coordinate registration for further received signals.

Abstract: A polarimetric imaging apparatus (2) and method for distinguishing objects of interest within a scene, said apparatus comprising means for resolving electromagnetic radiation received from the scene having a first substantially circular polarisation state into a first image and for resolving electromagnetic radiation received from the scene having a substantially circular polarisation state of opposite handedness to that of the first circular polarisation state into a second image so as to identify differences there-between, and means for providing an output indicative of the difference there-between, wherein the resolving means is arranged in use to resolve said electromagnetic radiation into said first and second images successively.

Abstract: A time delay beamformer comprises input channels, which have associated samplers arranged to sample inputs signal carried upon the input channels. The samplers sample the input channels at a number of points in time to produce a number of sampled signals. An adaptive processor receives each of the input signals and each of the sampled signals, and generates processed signals therefrom. Time delay devices introduce a steering time delay to the processed signals and a summer generates a beamformed output signal the delayed processed signals.

Abstract: A vehicle arresting device comprises a net intended to be laid flat on the ground in the path of a target vehicle with an array of upwardly-directed spikes attached to the net along a leading portion, so that when a vehicle runs over the device some of the spikes engage in its front tires and the net is caused to wrap around the front wheels, being pulled tight under the vehicle to prevent further rotation of those wheels. There are two rows of spikes, with the spikes in the second row being substantially longer than the spikes in the leading row. The gauge of the netting also varies, with the leading strip which includes the shorter spikes and back towards the longer spikes being of a thinner gauge, the portion from the longer spikes back to approximately the mid length of the net being of a thicker gauge, and the trailing portion reverting to the thinner gauge. These measures help to ensure that the net is capable of arresting a wide range of vehicles, from passenger cars to trucks.

Abstract: A multicore optical fibre includes a microstructured cladding material formed from a plurality of cladding elements arranged in an array and each cladding element comprising at least two different materials each having different refractive indices, and a plurality of core elements formed within interstitial regions between adjacent cladding elements. A fibre so formed may have a large number of cores per unit cross-sectional area as compared with prior art fibres, and thus allows the fibre to have relatively short distances between adjacent cores for a given required inter-core isolation. A fibre so formed has utility in many areas requiring high core density, such as inter-chip optical communication, or optical communication between circuit boards.

Abstract: A strain-responsive visual indicator comprises a pair of overlapping shutter strips (1, 2) adapted to be mounted to a substrate such that strain in the substrate causes relative movement M between them. Each shutter strip comprises an alternating set of windows (5) or (6) and bars (7) or (8) and the distal strip (2) is backed by a strip (3) of a different color exposed through its windows (6), or the distal strip can instead be printed with a set of alternating colors in place of its windows and bars. The effect is that under different strain conditions different color indications from the distal strip (2) will be visible through the windows (5) of the proximal strip (1), in accordance with the relative positions of the two strips. The indicator can be incorporated e.g. in the shaft of a toothbrush to give a visual warning in response to flexure of the shaft if excessive brushing pressure is applied. Numerous other applications and the use of different types of indicia are indicated in the specification.