Abstract: A fiber-radio communication network includes a base station (300) and wireless access nodes (100) coupled by fiber optic cables (125). The base station (300) includes a switch module (320) arranged to switch Ethernet signals on a local area network, and a media converter rack module (310) comprising media converter units MC1-MC6 arranged to convert between a baseband Ethernet signal carried by the fiber optic cables (125) and an Ethernet digital signal for the switch. The wireless access node (100) comprises a media converter module (120) which converts between a baseband Ethernet signal carried by the fiber optic cables and an Ethernet digital signal; and a wireless access point module (110) comprising a local modem which converts between the Ethernet digital signal received over the fiber optic cables and a wireless transmission in a 60 GHz range for wireless communication with a client terminal (400) in the vicinity of the wireless access node (100).

Abstract: A liquid storage system comprising: a tank for containing a liquid, the tank enclosing a liquid storage space; multiple layers of a fabric material; and attachment means attaching the multiple layers of the fabric material to an internal surface of the tank. The attachment means may comprise a non-permeable envelope attached to the internal surface of the tank. The multiple layers of the fabric material may be enclosed in the envelope such that the multiple layers of a fabric are isolated from a fluid in the tank. The envelope may contain a fluid (e.g. air) in addition to the multiple layers of the fabric material.

Abstract: A robust, durable, easy to use, reusable shipping container is disclosed that is capable of protecting contents from surrounding high temperatures up to 1000 degrees Fahrenheit for a minimum of at least three and a half hours. The container includes an inner chamber surrounded by an outer chamber. A phase change liquid (PCL) is sequestered in a porous support matrix contained in the inner chamber, while the outer chamber is filled with high temperature insulation, forming an outer barrier layer that is designed to reduce heat flux into the inner chamber.

Abstract: A method of producing an assembly tool (60) for assembling an assembly (6), the method comprising: providing at least a portion of a jig frame (62); fixing support plates (65) to the jig frame (62); machining the one or more support plates (65) such that a surface of each of the support plates (65) lies in a common plane (130); positioning the jig frame (62) such that the machined surfaces of the support plates (65) contact with a supporting surface (138); fixing pickup device mounting plates (140a, 140b) to the jig frame (62); machining, with respect to the supporting surface (138), the pickup device mounting plates (140a, 140b) such that a surface of each mounting plate (140a, 40b) has a respective predetermined position and orientation with respect to the supporting surface (138); and fixing, to the machined surfaces of the mounting plates (140a, 140b), a respective pickup device (66-72).

Abstract: A data processing method is disclosed for processing hyperspectral image data of a scene. The method comprises sequentially receiving portions of the data at a data buffer to form a data set comprising a predefined number of data portions and calculating a set of global statistical parameters and data correction factors using the data forming the data set. The method further comprises receiving a further data portion at the data buffer and simultaneously removing the earliest received data portion at the data buffer, from the data set, and subsequently calculating a set of local statistical parameters using the data of the further data portion. The method further comprises updating the set of global statistical parameters using the set of local statistical parameters and correcting the data of the data portion removed from the data set using the correction factors.

Abstract: There is disclosed herein a transducer for acoustic communications through a series arrangement of fluid and solid media, the transducer comprising: —a signal processor configured to implement a communications scheme at and around a center frequency of at least 1 MHz; a piezoelectric element for activation in accord with the communications scheme; an electrode electrically connected to the signal processor, and being attached to the piezoelectric element; and a substrate, having the piezoelectric element mounted thereon, wherein an aspect of the electrode at the piezoelectric element is approximately equal to the acoustic wavelength of an acoustic wave in the substrate at the center frequency. There is further disclosed a remote monitoring device employing at least one of the transducers described, in concert with a further transducer. Still further, there is disclosed a method of communicating using the transducer described herein.

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: The invention relates to improved structural health monitoring, particularly to structural health monitoring of fiber reinforced polymer composites, more particularly at bonded joints and methods thereof. There is provided a method of structural health monitoring a composite structure (12), wherein said structure (12) comprises at least one non-reinforcing thermal element (18), such as electrically conductive fibers, comprising the steps of applying a stimulus to cause heating of said thermal element (18), removing the stimulus, and measuring the electrical resistance of said element (18) as a function of time, to provide a thermal decay profile (41, 42) indicating whether damage has occurred in the composite structure (12).

Abstract: Apparatus and method are disclosed for co-aligning a number of laterally displaced radiation beams from respective radiation source outputs, each beam having a respective waveband. The apparatus comprises a collimating element for receiving each of said radiation beams with respective lateral displacements and a combining element for receiving each of said radiation beams passed by said collimating element. The apparatus further comprises a radiation source mount for positioning the radiation source outputs relative to the collimating element. The method comprises longitudinally positioning the radiation source outputs upon the mount, relative to the collimating element, in dependence upon the waveband of each beam, to cause the radiation beams passed by the combining element to be co-aligned.

Abstract: A method of sensing strain in a structural component, the method comprising the steps of providing, embedded within said structural component, at least one carbon fibre element (10) coated with an electrically conductive material (12), measuring the electrical resistance of said coated carbon fibre element and determining strain in respect of said carbon fibre element based on changes in said electrical resistance thereof. A method of manufacturing a carbon fibre element, a carbon fibre element so manufactured, and a carbon fibre reinforced structural component including such a carbon fibre element are also disclosed.

Abstract: A Peltier effect heat transfer system (208) comprising: a plurality of heat transfer elements (301-308); wherein each heat transfer element (301-308) comprises at least one semiconductor element pair arranged to yield Peltier effect heat transfer, each semiconductor element pair comprising a P-doped semiconductor element (408) and an N-doped semiconductor element (410); and the heat transfer elements (301-308) are independent such that each heat transfer element (301-308) can be activated so as to yield Peltier effect heat transfer independently of each other heat transfer element (301-308).

Abstract: A method for suppressing the Jet Engine Modulation (JEM) clutter signal returns from compressor blades (26) in data sampled by a system for Foreign Object Debris (FOD) detection in the air intake (30) of a turbine assembly, the method comprising the steps of: (a) identifying in the data the start sample position and length in samples of a single complete shaft rotation; and (b) subtracting from a current rotation dataset the samples from a comparison rotation dataset corresponding to another complete single shaft rotation.

Abstract: A method for displaying an image to a pilot (20) of an aircraft (2). The method comprises: displaying, by a helmet mounted display (HMD) (24), to the pilot (20), an image comprising initial image components including a first image component (34); determining that the helmet mounted display (24) is offset from a desired position for the helmet mounted display (24); determining, by one or more processors (26), a specification for a further image component (50); and displaying, by the helmet mounted display (24), to the pilot (20), an image comprising at least the first image component (34) and the further image component (50). The further image component (50) has a fixed position with respect to the first image component (34) and indicates one or more alternative positions for the first image component (34).

Abstract: A method and apparatus for displaying an image to an aircraft pilot (20). The method comprises: displaying, by a display (24), to the pilot (20), an image comprising guidance symbology (34) for use by the pilot (20) when landing the aircraft (2), the position of the guidance symbology (34) on the display (24) being dependent upon an output of an INS of the aircraft (2); providing, to a processor (26), an indication that the INS output is incorrect; determining, by the processor (26), a further value for the INS output and a specification of further guidance symbology (40); and displaying, by the display (24), to the pilot (20), an image comprising the further guidance symbology (40). The position on the display (24) of the further guidance symbology (40) relative to that of the guidance symbology (34) is dependent upon the difference between the further value and the incorrect INS output.

Abstract: Methods and apparatus for producing and assessing at least part of an object (2), the methods comprise: performing, using Additive Manufacturing apparatus (8), an Additive Manufacturing process to produce a test specimen (30, 34, 38) and at least part of an object (2); performing, using micro-tomography apparatus (40), on the test specimen (30, 34, 38), a micro-tomography process to create a digital model (50) of the internal structure of the test specimen (30, 34, 38); determining whether or not the model (50) satisfies one or more criteria; and, if the model (50) satisfies the criteria, determining that the at least part of the object (2) produced by performing the Additive Manufacturing process is acceptable, or, if the model (50) does not satisfy the criteria, determining that the at least part of the object (2) produced by performing the Additive Manufacturing process is not acceptable.

Abstract: A baffle system includes a baffle (40) located in a tank (16) for containing liquid (e.g. an aircraft fuel tank). The baffle (40) is a tubular member through which a liquid may flow. The baffle (40) comprises: a first tubular portion (42) providing a tubular outer wall, and a second tubular portion (44) located within the first tubular portion (42) and providing a tubular inner wall. The first and second tubular portions (42, 44) are substantially parallel. The first and second tubular portions (42, 44) are spaced apart to define a chamber (46) therebetween. The baffle (42, 44) further comprises radial side walls between the first and second tubular portions (42, 44) such that the chamber (46) is a sealed chamber. The chamber (46) may be filled with a compressible gas or gaseous mixture.

Abstract: A method for suppressing the Jet Engine Modulation (JEM) clutter signal returns from compressor blades (26) in data sampled by a system for Foreign Object Debris (FOD) detection in the air intake (30) of a turbine assembly, the method comprising the steps of: (a) identifying in the data the start sample position and length in samples of a single complete shaft rotation; and (b) subtracting from a current rotation dataset the samples from a comparison rotation dataset corresponding to another complete single shaft rotation.

Abstract: Methods and systems are disclosed for radio positioning of a vehicle using a virtual positioning reference established by logging a known position of the vehicle together with a local time that a first instance of a predictably repeated code word is received from an opportunistic terrestrial radio transmitter. During movement of the vehicle to a second, unknown position, a local clock is used to determine the time difference between when the virtual positioning reference is predicted to receive a second instance of the code word and when the vehicle actually receives the second instance of the code word, thereby providing positioning information when traditional navigation signals such as GPS are not available. The radio positioning information is then used to initiate an action such as recording the location information for future retrieval by a user, and/or controlling the movements of an autonomous vehicle.

Abstract: A system comprising a low observable aircraft (2) having its surfaces oriented at a limited number of directions, and a lightning diverter strip (4, 22, 30) comprising a plurality of electrically conductive elements (8, 24, 32) arranged in a spaced apart relation, each of the electrically conductive elements (8, 24, 32) comprising an elongate portion. The lightning diverter strip (4, 22, 30) is attached to the aircraft in such a way that the conductive elements (8, 24, 32) are located on an exposed outer surface of the lightning diverter strip (4, 22, 30) and exposed to atmospheric conditions. For each conductive element (8, 24, 32), a long axis of the elongate portion of that conductive element (8, 24, 32) is substantially parallel with a surface of the aircraft.

Abstract: A heat exchanger (2) comprising a duct (4) through which a first fluid (e.g. a coolant such as ram air) may flow, and one or more vanes (18) disposed within the duct (4) and configured to disrupt the flow of the first fluid through the duct (4). Each vane (18) comprises one or more flow channels (24) through which a second fluid (e.g. a fluid to be cooled, such as engine coolant) may flow so as to transfer heat between the first fluid flowing through the duct (4) and the second fluid flowing through the one or more flow channels (24). The flow channels (24) within the vanes (18) are separated from the duct (4) by a channel wall such that fluid cannot flow between the duct (4) and the flow channels (24).