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HOT BIRD 3 Scheduled for September Launch
The European Television Satellite (EUTELSAT) provider's HOT BIRD 3 television (TV) broadcast satellite was scheduled to be launched in September aboard an Ariane rocket fired from Kourou, French Guyana. HOT BIRD 3 was developed by the Franco-British Matra Marconi Space consortium, and is the second of a new series of direct TV broadcast satellites built for EUTELSAT. HOT BIRD 2, the satellite's predecessor, was placed in orbit on November 21, 1996. According to its manufacturer, HOT BIRD 3 is Europe's largest TV satellite to date and is designed to serve both digital and analogue TV systems. As such, the vehicle utilises the latest version of Matra Marconi's 2.8 X 1.7 X 2.5 m EUROSTAR satellite bus and is equipped with a solar panel array (spanning 27.9 m when deployed) and 20 repeaters operating on a range of broadcast and fixed satellite services subfrequencies within the 11 to 14 GHz and 12 to 18 GHz frequency bands. Each repeater package incorporates a fixed receive antenna and a 124 W travelling-wave tube amplifier. Two 2.3 m (dia) deployable, dual-gridded transmission antennas and a 50 cm (dia) steerable array complete the vehicle's 339 kg payload. Each repeater can handle several digital broadcasts simultaneously using digital compression techniques. Channel bandwidths are 33, 36 and 72 MHz. If launched successfully, HOT BIRD 3 will be positioned in a geostationary orbit at 13° East, 36,000 km above the equator and will offer wide beam coverage of Europe (from the Azores to Kazakhstan), so-called superbeam coverage of Europe and North Africa, and spot coverage (using the steerable antenna) of any location on the globe's surface that is visible from its orbital position. Coverage is in-orbit selectable and, when the five-satellite HOT BIRD constellation is completed in 1998, the overall system will reportedly be able to transmit approximately 100 analogue channels, up to 800 digital channels or a combination of the two. HOT BIRD 3 has a designed in-orbit life of 15 years.
LMES Awards Racal-Thorn FOTD TG Contract
Lockheed Martin Electronic Systems (LMES), Yonkers, NY, has awarded UK contractor Racal-Thorn Defence a contract valued at more than £10 M to develop and fabricate a RF techniques generator (TG) for the fiber-optic towed decoy (FOTD) version of Raytheon E-System's model AN/ALE-50 equipment, which is to be fitted to the UK's next-generation Nimrod MR.4 maritime reconnaissance aircraft. Reportedly, both Racal and GEC-Marconi competed for this contract, which involves Racal in the delivery of a TG integration model to LMES in September 1998. Thereafter, the equipment will be subjected to a year-long trial programme prior to entering production. All 21 Nimrod MR.4 aircraft being procured are to be fitted with the equipment and additional systems will be produced as spares. The new Racal FOTD TG is based on the company's work with the UK's Defence Evaluation and Research Agency on the advanced jamming system technology demonstration programme. As applied to the Nimrod aircraft, the system will be mounted in a 48 cm rack and incorporate digital RF memory technology with integral threat parameter and countermeasures technique software libraries. Interfacing with and cued by LMES' model AN/ALR-56M(V) radar-warning receiver, the TG will generate a coherent response and function in noise, deception and repeater modes. When compared with existing towed radar decoy systems, the new system is expected to triple the number of simultaneous threats able to be countered in a single deployment. Alongside the Nimrod MR.4 effort, Racal and Lockheed Martin have agreed to collaborate on the use of the British-sourced TG in Lockheed Martin's future large aircraft defensive aid system business. Targets are likely to include next-generation maritime patrol programmes in Germany, Italy and the Pacific together with defensive aids provision for the Lockheed Martin model C-130J Hercules transport aircraft. Reportedly, discussions are underway between Racal and Raytheon E-Systems concerning future towed decoy system cooperation while Racal intends to repackage the system for both shipboard and fast-jet applications.
Swedish Antenna Evaluation Range Detailed
In collaboration with Sweden's Defence Material Administration's Test Directorate, contractor FFV Aerotech has constructed an open-air antenna test range in Arboga, Sweden. The range is designed to facilitate the test and evaluation of antennas (including adaptive types) and other electronic systems in a countermeasures environment, and includes two fixed and two deployable RF sources and a hydraulically actuated 25 m tower on which full-sized aircraft can be positioned. Aircraft orientation is established by a three-dimensional pointing system and, when not in use, the tower and test item are retracted into a 20 X 12 X 5 m underground hanger. The range's control room and support facilities are also located underground to minimise unwanted reflectivity. Other test items (including ships and vehicles up to the size of main battle tanks) are located on a separate flush-mounted azimuth positioner capable of accommodating weights of up to 90 tons. The range operates across the 20 MHz to 18 GHz frequency range with signals below 4 GHz using a ground reflection mode. Each of the RF sources can produce vertical, horizontal or circular polarisations and the overall system has a dynamic range of better than 60 dB; an amplitude accuracy of ±1 dB; and angular accuracies of ±0.1° and ±0.05° for the airframe tower and azimuth positioner, respectively. Data acquisition (using a model HP8530A receiver) is fully automatic and a provision exists for a frequency extension of up to 100 GHz.
RN to Standardise Blue Water ES Provision
The August award of a £25 M contract to UK manufacturer Racal-Thorn for an undisclosed quantity of its Outfit UAT systems completes an ongoing exercise that will see the UK royal navy (RN) standardise on UAT for electronic support (ES) provision within its blue water surface fleet. The Outfit UAT system is designed to detect, identify and classify radar threats, and is a RN-configured, software-controlled variant of Racal's Sceptre XL system, which comprises an eight-port, masthead antenna array; a receiver/processor; and an operator's console. The equipment can operate as a stand-alone system or can be integrated with the host vessel's overall command and control system. Processing is based on a series of transputers, and the operator console used incorporates two display screens showing situational and alphanumeric tabular information. In terms of fleet provision, the Outfit UAT system is already installed aboard four of the RN's planned 16-ship type-23 frigate class and is on order for the helicopter carrier Ocean (UAT(4) variant), the fleet auxiliaries Fort Grange and Fort Victoria, and the amphibious transport docks Albion and Bulwark (both UAT(4) variant). Additional systems (designated UAT(2) and UAT(3)) have been acquired for those type-23 frigates already fitted with Racal's Outfit UAF(1) ES system; the vessels currently under construction; and the RN aircraft carriers Ark Royal, Illustrious and Invincible. UAT will replace Outfit UAF(1) aboard Illustrious and Racal's Outfit UAA(2) equipment aboard Ark Royal and Invincible. The carrier element of the new contract is likely to follow the procedure established for the Outfit UAA(2) mid-life update that Racal has been contracted to carry out aboard RN type-42 air-defence destroyers and type-22 antisubmarine warfare frigates. Under this March 1996 award (valued at approximately £36 M), the inboard electronics of the UAT system are being mated with the existing UAA(2) antenna array to create a UAT standard equipment. It is not yet clear how the RN intends to designate this hybrid system.
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