Abstract

A passive system is described for detecting radar emissions from vessels, receiving the radar emissions and analysing the data using a series of algorithms and software manipulation to extract radar signatures representative of the identity of the vessel. The data output is capable of comparison with a stored set of data enabling accurate identification of the vessel. The resulting output is displayed on a suitable display. A system having a library of vessel emission signatures can either be created within the operator s library through measurement made, or it can be supplied from a central database. The system is capable of installation on sea, land or air-based platforms.

IPC Classes  ?

• G01S 7/02 - Details of systems according to groups , , of systems according to group

Abstract

This invention relates to utilising a larger number of lower power transmit/receive modules in a phased antenna array in order to utilise cheaper and simpler transmit/receive modules whilst retaining comparable power per unit area as can be achieved through using conventional high powered transmit/receive modules. The advantage of this arrangement is that cheaper antenna arrays can be constructed without limiting the capability and/or performance of a system incorporating such an array when compared to a conventional solution.

IPC Classes  ?

• H01Q 21/00 - Antenna arrays or systems

Abstract

This invention relates to reducing the complexity and cost of antenna arrays and is more specifically concerned with reducing the complexity of an antenna apparatus. It provides an antenna array (62) made up of a vertical stack of horizontal linear structures (74) each having several groups of neighbouring array antenna elements, the groups (74) having variable numbers of the antenna elements each connected to a transmit/receive module (66) . The advantage of this configuration is that less communication modules (66) , such as transmit/receive modules, are required to operate the antenna array (62) , reducing the weight, power consumption and cost of an antenna apparatus incorporating such an antenna array (62) without significantly limiting the capability and/or performance of a system compared to a conventional solution.

IPC Classes  ?

• H01Q 21/00 - Antenna arrays or systems
• H01Q 3/26 - Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elementsArrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the distribution of energy across a radiating aperture

Abstract

Described herein is a multi-colour radiation detector that comprises a mesa-type multi-layered mercury-cadmium-telluride detector structure (10) monolithically integrated on a substrate (6). The detector is responsive to three or more discrete wavelength ranges and means is provided whereby each of the wavelength ranges can be detected independently or in combination with others of the ranges.

IPC Classes  ?

• H01L 31/101 - Devices sensitive to infrared, visible or ultraviolet radiation
• H01L 27/146 - Imager structures
• H01L 31/0296 - Inorganic materials including, apart from doping material or other impurities, only AIIBVI compounds, e.g. CdS, ZnS, HgCdTe

Abstract

A microwave, power splitter/combiner (20) is formed as part of a multilayer laminate (27, 28, 29, 33, 34) such that two ports (22, 23) are connected by plated vias (31 , 32) to conductive pads (29, 30) connected across an isolation resistor (27). Furthermore, a microwave circuit is provided in the form of a multi-layer laminate including a substrate carrying a resistive layer which has been etched to define at least one resistor, a dielectric membrane covering the resistor, a conductive layer defining at least part of an electrical circuit, and said at least one resistor is electrically connected to the conductive layer by vias extending through the dielectric membrane.

IPC Classes  ?

• H01P 5/16 - Conjugate devices, i.e. devices having at least one port decoupled from one other port
• H01P 11/00 - Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type

Abstract

This invention relates to a radiating element (20) for use in array antennas. The radiating element (20) is of simplified design and comprises a front region (26) and a rearward region (28) that are preferably substantially rectangular, which permit higher frequency limits than more conventional Vivaldi elements while maintaining the lower frequency limit. Additionally, by deployment of an array of a plurality of such elements (20) such that no gaps are formed between adjacent elements (20) along the array antenna, very wide bandwidth can be obtained using the array.

IPC Classes  ?

• H01Q 13/08 - Radiating ends of two-conductor microwave transmission lines, e.g. of coaxial lines, of microstrip lines
• H01Q 21/06 - Arrays of individually energised antenna units similarly polarised and spaced apart
• H01Q 21/24 - Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction

Abstract

A method for preventing spatial or spectral beam seeding in a Q- switched laser is described. The Q-switch trigger of the laser is delayed by several laser resonator lifetimes after the end of the pump pulse. In this way, beam seeding is completely eliminated whilst pre-lase is maintained. The method described may be used for any laser system where the fall time of the pump radiation is sufficiently fast with respect to the upper state lifetime of the laser medium.

IPC Classes  ?

• H01S 3/11 - Mode lockingQ-switchingOther giant-pulse techniques, e.g. cavity dumping
• H01S 3/0941 - Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a semiconductor laser, e.g. of a laser diode
• H01S 3/16 - Solid materials

Abstract

A transmitter (106, 120, 118, 122 and 110) of a platform (100) is arranged to generate a transmission pulse which is transmitted to a receiver (212, 224 and 208) of another platform (200) and is also arranged to couple its transmission pulse to a digital receiver (104) associated with its platform (100) via attenuater (126) and coupler (124). The other platform (200) performs a similar task. Each digital receiver (108, 208) determines the time separation between its transmission pulse and received pulse from the other platform (100 or 200). The determined time separation information is shared with the other platform (100, 200) and each digital receiver (108, 208) then determines a time offset (ﶴt) between the time at its platform (100) and the other platform (200).

IPC Classes  ?

• G04G 7/02 - by radio

Abstract

A specialist tow cable termination for sustaining the tensile load when an object (9) is towed at high speeds at the end of an cable behind an aircraft, the termination comprises a closed eye bolt (3) attached to the cable and a U-bolt looped through the eye bolt attached to the object. The arrangement allows 5 significant pivoting bending stresses to the tow cable.

IPC Classes  ?

• F41J 9/10 - Airborne targets, e.g. drones, kites, balloons towed
• F16G 11/00 - Means for fastening cables or ropes to one another or to other objectsCaps or sleeves for fixing on cables or ropes