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Northrop Grumman Enters Bid for ASTOR
The recent Battlefield Systems International ’98 trade exhibition and conference has provided the first clear details of a last-minute bid into the UK’s Airborne Standoff Radar (ASTOR) programme made by a consortium led by US contractor Northrop Grumman. The team is competing with consortia led by Lockheed Martin UK Government Systems Ltd. and Raytheon Systems Ltd.
The Northrop Grumman system would be mounted in a modified Gulfstream V business jet and utilize a high performance, next-generation radar modeled after Northrop Grumman’s work in the radar surveillance/airborne warning and control fields. As such, the sensor meets all ASTOR requirements and offers concurrent spot synthetic aperture radar (SAR)/variable swath SAR/moving target indicator modes. The same technology forms the basis of a bid to replace the US APY-X APY-2 surveillance radar, which currently is fitted to the US Air Force’s E-8 Joint Surveillance Target Attack Radar System aircraft.
Operated by a six-man crew (including four system operators), Northrop Grumman’s ASTOR proposal also includes an extensive communications suite and the ability to accommodate plug-and-play radar, signals intelligence and electro-optic reconnaissance sensor packages. In terms of the communications capability, the system utilizes high frequency, VHF and UHF radios; satellite links; and the next-generation L3/Northrop Grumman multimode data link system. The specified mix of communications subsystems reportedly will enable the airborne platform to act as a surrogate satellite for its ground stations.
With regard to the proposal’s ground element, air transportable operational level stations and vehicle-mounted tactical stations are envisaged. The motive unit to be used for the tactical stations is a wheeled Steyr cross-country vehicle.
Sweden Orders New Coastal Defence Radar
Sweden’s Defence Materiel Administration has awarded national contractor Ericsson Microwave a $45 M development and construction contract covering the procurement of an unspecified number of G-/H-band (4 to 8 GHz) Giraffe CD surveillance radars for use by the Swedish Navy’s coastal artillery force. Giraffe CD (military designation ARTE 740) is the latest model in the Giraffe family to be developed and is designed to provide a combined air/surface surveillance and command and control capability for mobile coastal artillery units. System features include vehicle mounting (using an armoured Mowag chassis), a 15-m-high deployable antenna mast, and high resolution surface search and fire-control operating modes.
The terms of the contract call for Ericsson to develop and supply the necessary radar units. Elements such as vehicles, display and communications subsystems, and antenna masts will be supplied by subcontractors. As scheduled currently, a prototype Giraffe CD will be delivered in 2001 with production starting the following year.
EUTELSAT to Obtain New Broadcast Satellite
The Paris, France-based European Telecommunications Satellite (EUTELSAT) organisation is procuring a new broadcast satellite from Matra Marconi Space (MMS) under the designation Europesat-1B. EUTELSAT already operates three MMS-built HOT BIRD television satellites and is scheduled to launch a fourth this fall. The new Europesat-1B vehicle, which will have a launch mass of 3 tonnes, is based on MMS’s EUROSTAR family of spacecraft.
The vehicle’s payload will comprise 36 repeaters operating at selected frequencies within the 11 to 14 GHz and 12 to 18 GHz bands allocated to broadcast and fixed satellite services. Individual channel bandwidth is 33 MHz and each onboard repeater will be equipped with a 70 W traveling-wave tube amplifier. In terms of antennas, the vehicle will be equipped with two deployable, dual-gridded fixed beam reflectors and two steerable elliptical beam arrays. Located in a 29º east geostationary orbit 36,000 km above the equator, Europesat-1B is expected to offer a footprint that covers most of the European landmass. Orbital lifetime is 12.5 years.
Japan Addresses Mobile Telephone Scourge
In an effort to reduce the use of mobile telephones in public locations, Japan reportedly may soon offer low cost mobile telephone jammers. In a country with approximately 30 million mobile telephones, the national telephone engendered noise nuisance problem is so great that the Japanese government is considering the legalisation of the approach in venues such as theatres and concert halls. In terms of hardware, Japanese contractor Nikkodo is producing jamming systems for use in hospitals and restaurants while the Tokyo-based manufacturer SIC is developing a hand-held unit with an effective range of 3 m that retails for approximately $174.
While such a jammer may appear to be an attractive solution to the problem, there is concern that the capability is open to abuse. Accordingly, the Japanese are researching a licensing system whereby the use of personal telephone jammers would be restricted to areas where mobile telephone use could be deemed a significant public disturbance. Use of the devices elsewhere would be subject to penalties.
UK Evaluating Radar for Mine Detection
As a byproduct of ongoing global concern about the indiscriminate lethality of land mines, UK companies are actively considering the potential of radar as a means of mine detection and mapping. At the most advanced stage is the UK Defence Evaluation and Research Agency’s (DERA) Remote Minefield Detection System technology demonstration programme. As part of this effort, DERA has awarded national contractor Systems Engineering & Assessment Ltd. (SEA) a £1 M contract to produce a prototype ultra-wideband synthetic aperture radar (UWBSAR) that is capable of detecting mines from the air. The system reportedly has the widest bandwidth of any radar currently under development in Europe.
The demonstrator radar will be mounted in an airship for trials and have bandwidth and pulse duration values of approximately 3000 MHz and 100 picoseconds, respectively. The UWBSAR’s RF front end and antenna are being developed by subcontractor Protec Research Ltd., and Kentech Instruments Ltd. is supplying fast pulse generators and UWB digitisers. In addition, DERA is contributing sensor design expertise and the University of Bath is evaluating risk-reduction options. Following design approval, system construction is expected to span approximately 12 months with SEA building the prototype to be integrated (together with control, monitoring and data recording subsystems) into an Airship Technologies airship. SEA also is producing an associated ground station.
Racal Thorn Wells also has demonstrated a digital processing capability that is able to detect surface mines using radar mounted in a jet aircraft at standoff distance. The company is studying an enhanced variant of its proprietary airborne data acquisition system (ADAS) as both a mine detection and foliage penetration sensor. Currently used as part of the contractor’s radar cross-section measurement programme, the ADAS is helicopter mounted and, in its latest form, features very large single pulse bandwidths when operating in the VHF/UHF (30 MHz to 1 GHz) band together with the ability to blank specific frequencies within individual pulses. Recent reports suggest that Racal Thorn Wells may be involved in a funded specification development study for a foliage penetration radar based on the ADAS technology.
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