Abstract: A waveguide comprising first and second waveguide sections, each waveguide section comprising a main body portion (12) and a connecting portion (14) at its distal end, said first and second waveguide sections being longitudinally aligned to define a conduit therethrough with a butted interface (28) therebetween, the connecting portion of each waveguide section having: (i) a first circumferential ridge (16) on its outer surface located adjacent its distal end, (ii) a second circumferential ridge (18) on its outer surface spaced apart from the first circumferential ridge, and (iii) a third circumferential ridge (20) on its outer surface located between said first and second circumferential ridges, such that a first respective recess (19) is defined between said second and third circumferential ridges and a second respective recess (17) is defined between said first and third circumferential ridges; the waveguide further comprising a sleeve member (22) over said butted interface (28), such that a respective firs

Abstract: A method and apparatus are provided for determining the orientation of an object relative to a moving or moveable platform. The object may for example be a helmet worn by a pilot of an aircraft in which orientation of the helmet relative the aircraft while in flight may usefully be known, in particular when determining the position of space-stabilised symbols being displayed in an associated helmet-mounted digital display system. The method and apparatus rely upon a combination or orientation rate data output by an inertial sensor arrangement associated with the object and orientation data output by a non-inertial tracker system associated with the object. Orientation data of the moveable platform is also used to reference the non-inertial tracker output to inertial space.

Abstract: A method and apparatus are provided for generating image data for output to a display device such as a HUD or HMD for display and for the validating image data being output to an applicable standard. The image generator comprises an interfacing component, an image rendering component implementing at least one image rendering function and an integrity monitor. The interfacing component receives drawing commands from external systems defining an image to be displayed and derives rendering and other control commands according to a predefined command set recognisable by the image rendering component. The image rendering component generates a set of image data from received rendering commands in the predefined set. The integrity monitor includes a rendering simulator arranged to simulate the at least one image rendering function to generate a nominally identical set of image data from received drawing or rendering commands.

Abstract: A lens design method is disclosed for designing a lens to reshape an actual far-field radiation pattern of a radiation source, such as a spiral antenna, to a preferred far-field radiation pattern. The method comprises:—determining a preferred far-field radiation pattern of the radiation source;—deriving a corresponding near-field radiation pattern from the preferred far-field radiation pattern;—determining an actual near-field pattern of the radiation source;—mapping an electric field and a magnetic field of the actual near-field radiation pattern to the derived near-field radiation pattern using a transfer relationship, the transfer relationship comprising material parameters which characterize the lens; and,—determining the material parameters.

Abstract: Disclosed is a method of detecting an anomalous propagation condition in a Radar system, comprising the steps of: subtracting returns received in a first receive period from returns received in a succeeding second receive period, and repeating this step for a plurality of receive periods; and if the step of subtracting gives a result in excess of a predetermined threshold in one of the plurality of receive periods, then registering this as a possible anomalous propagation condition.

Abstract: A method and apparatus for assessing a calibration of a multi-axis ultrasonic scanner, the method comprising: providing a calibration verification tool (100), comprising a plurality of mutually oblique plates (110-140) defining surfaces at predefined angles with respect to one another; providing a digital model of the tool; registering, by the ultrasonic scanner, the tool (100) within the reference frame; controlling the ultrasonic scanner to measure a plate (110-140) to determine a reference signal; measuring each plate (110-140); using the reference signal and the plate measurements, determining an orientation of the ultrasonic scanner when each plate was measured; and, using the determined orientations, verifying whether or not the ultrasonic scanner calibration.

Abstract: A mobile bridge apparatus includes one or more mobile bridge modules and a plurality of sensors for sensing a deformation of the one or more mobile bridge modules.

Abstract: Apparatus for management of communications resources of a moving platform comprising an on-board communications system configured to effect wireless data communication between said moving platform and another node, said communications resources comprising a plurality of wireless communications links and a plurality of antennas associated therewith, the apparatus comprising an antenna analysis and selection module residing with said communications system and configured to: —receive, during a mission from one or more systems/subsystems and/or functions of said moving platform, attribute data representative of said emissions control criteria, said attribute data comprising (i) location data representative of a specified emissions control region, and/or (ii) position and/or attitude and/or velocity data representative of an adversary node defining an emissions control region; —determine, using said attribute data and based on said emissions control criteria, suitability of one or more on-board antennas and/or por

Abstract: An optical selector arrangement (22), comprising: a first set of optical ports (30), having a first number of optical ports, the first number being greater than or equal to 2; a second set of optical ports (42), having a second number of optical ports, the second number being greater than the first number; the second set of optical ports being for communicating with the first set of optical ports, a selector interface (40) for the optical selector arrangement, the selector interface comprising the second set of optical ports (42), a part of the optical selector arrangement functioning as a selector (44), the selector being arranged to selectively optically couple the first set of optical ports (30) to a set of ports of the second set of optical ports (42) of the selector interface, the selector (44) being rotatable relative to the selector interface (40) to facilitate the selection by optically aligning the first set of optical ports (30) to the second set of optical ports (42) of the selector interface (40);

Abstract: Disclosed is a lighter than air vehicle comprising: an envelope containing a lighter than air gas, at least part of the envelope admitting the passage of light through the at least part of the envelope; and a directing device for selectively redirecting the light which passes through the at least part of the envelope. The vehicle may further comprises a plurality of devices for using incident light. The directing device for selectively redirecting the light may be for selectively redirecting the light onto a selected device, for example, by switching the positions of two or more devices into the path of the light.

Abstract: There is disclosed a surveillance apparatus comprising: —a retractable support member the member having a first end and a second end; a housing; a spooling mechanism mounted at the housing, and being rotatable relative to the housing, and being attached to the second end of the retractable support member, the spooling mechanism being: Operable to rotate in a first direction to convert the retractable support member from a coiled condition to an extended condition and thereby pay-out the support member from the housing, Operable to rotate in a second direction opposite to the first to convert the retractable support member from the extended condition to the coiled condition and thereby retract the support member into the housing; A mount attached to the first end of the retractable support member; A surveillance device attached to the mount for receiving environmental signals, a human interface remote from the surveillance device; and an electrical connection operably connecting the surveillance device to the

Abstract: A liquid storage tank, for example an aircraft fuel tank, having a tank wall enclosing a liquid storage space, and a tie assembly located at least partially within the liquid storage space. The tie assembly includes an elongate member, for example a wire or cable, and a plurality of attachment devices fixed to an inner surface of the tank wall. The elongate member includes a plurality of spaced part points along its length, each of the spaced apart points being fixed to a respective attachment device such that the tie assembly resists outward deformation of the tank wall.

Abstract: The invention relates to a cast explosive composition comprising a polymer-bonded explosive and a defoaming agent, and to a process for reducing the number and/or total volume of voids in a cast explosive composition comprising the steps of: combining a polymer-bonded explosive and a defoaming agent; and casting the explosive composition. The defoaming agent may be used for reducing the number and/or total volume of voids in a cast explosive composition and the cast explosive composition may be used in an explosive product.

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: An assembly process for assembling at least part of an aircraft airframe, the assembly process comprising: providing a first assembly including a first part of the airframe and a first reference structure attached thereto; providing a second assembly including a second part of the aircraft airframe and a second reference structure attached thereto; receiving, by a first receptacle, the first reference structure; receiving, by a second receptacle, the second reference structure; moving, by an actuation device, the receptacles into a predetermined configuration, thereby moving the first part of the aircraft airframe and the second part of the aircraft airframe into a predetermined configuration; and performing an assembly operation on the airframe parts to fixedly attach together the first part of the aircraft airframe and the second part of the aircraft airframe, thereby producing the part of the aircraft airframe.

Abstract: A method is provided for securing a mobile communications device to a level required for accessing a network, for example a secured enterprise network, by means of a public network such as the Internet. A mobile communications device is also provided incorporating functionality to enable centralized control over the configuration of the mobile device and thereby to control the actions of users of that device and of applications software that may be installed and executed on that device. Furthermore, a system is provided to implement a mobile communications infrastructure for an enterprise network with centralized control over the configuration of mobile communications devices within the system.

Abstract: The following invention relates to smart material couplings, particularly to shape memory alloy drivetrain systems to mitigate against shock or blast. There is provided an armoured land vehicle comprising:—an armoured v shaped hull; a powerplant located within said chassis, at least one wheel set with a hub, and, at least one drive shaft comprising a shape memory alloy, wherein said drivetrain is located between and operably connected via drive couplings to said powerplant and the hub of the at least one wheel set, to provide drive to said at least one wheel set.

Abstract: The following invention relates to an optical device for use in a system that requires optical zoom or focus abilities, particularly for providing pre-set zoom parameters with a very low energy requirement. There is provided an optical magnification device comprising at least one pair of optically aligned deformable reflectors, wherein each reflector pair has at least two configurations, wherein selection of a first and a second configuration of said deformable reflector pairs provides pre-defined magnification states, such that in any configuration one reflector is substantially concave and the other is substantially convex; at least one controller may cause both the reflectors to move between said at least two configurations.

Abstract: A machine is on a first side of a plate. A cable, a bundle of cables, a pipe carrying a fluid to or from the machine, a conduit, or any combination of these, passes along or through the plate. The plate is susceptible to vibrations arising from operation of the machine. An active vibration suppressor is mounted on the cable(s), pipe, or conduit, and a controller is configured to control the active vibration suppressor to suppress vibrations of the plate.

Abstract: A system for remotely sensing light emanating from within a monitored environment. The system comprises one or more retro-reflective optical elements bearing an optically reflective optical coating upon a surface thereof and positionable within the environment to be monitored, and a light source arranged to direct a beam of light at the optical element(s). A detector is arranged to receive from the optical element(s) light returned by the optical coating in response to the beam of light and to detect a property of the monitored environment according to said returned light. The optical element includes a body comprising a focuser part of positive optical power partly surrounded by a reflector part separated therefrom and connected thereto across an open spacing. The optical coating is arranged over an outer surface of the reflector part thereat to receive light which has been at least partially converged by the focuser part for subsequent retro-reflection.