New Matra Marconi Satellite to Boost Asian Coverage
Matra Marconi Space's ST-1 telecommunications and direct broadcast satellite was launched in August from Kourou, French Guiana into an 88º east orbit. In this position, the satellite will provide Ku-band (11.45 to 12.75 GHz and 14 to 14.5 GHz) direct broadcast services to India, Southeast Asia and Taiwan together with C-band (3.4 to 3.7 GHz and 6.4 to 6.7 GHz) coverage from western India and Pakistan to Borneo, the Philippines and southeastern China.
Jointly commissioned by Singapore Telecom and Taiwan's Chunghwa Telecom International, ST-1 is based on Matra Marconi Space's EUROSTAR platform and has a launch mass of 3255 kg. The vehicle's 443 kg payload comprises 16 Ku-band transponders and 14 C-band transponders with a total power requirement of more than 6.5 kW. Channel bandwidths at Ku- and C-bands are 54 and 36 MHz, respectively, while the vehicle's RF high power amplifiers provide an output of 67 W at C-band and between 90 and 135 W at Ku-band. ST-1 features an extensive antenna array that comprises 1.2 m Gregorian C-band receive, 1.7 m Gregorian Ku-band transceiver, 2 m dual-grid-shaped C-band transmit and 2.5 m Gregorian Ku-band transceiver reflectors.
Designed to have an operational lifetime of 13 years, the $240 M ST-1 programme includes the satellite, its delivery into orbit, the establishment of associated ground stations in Singapore and Taiwan, and a comprehensive training and support package. Matra Marconi Space reports that ST-1 has completed in-orbit tests of its bus and embarked on in-orbit payload trials prior to service entry.
SLIMDIS Program Proves Display System Feasibility
The UK's Slim Display (SLIMDIS) technology demonstration programme recently proved the feasibility of miniature silicon backplane colour liquid crystal displays for use in applications such as head- or helmet-mounted display systems. During the demonstration, an active matrix pixel array and drive circuitry were fabricated on a 16.3 ¥ 16.3 mm silicon substrate using a 0.7 mm CMOS process from a commercial foundry. In such an application, an alignment layer of obliquely evaporated SiO2 or buffed nylon is deposited onto the silicon backplane and a front glass substrate. The glass substrate is coated with indium tin oxide to form a transparent electrode. The backplate and front substrate are bonded together using ultra-violet cured epoxy, and 2.4 mm quartz spacer rods are used to define cell thickness. Each cell is capillary filled with CS1031 liquid crystal, sealed and package mounted. The device has a 1024 ¥ 768 pixel display array on a 12 mm pitch, producing a 12.3 ¥ 9.2 mm active area. Data are transferred onto the display via a 64-bit bus at a clock rate of 62.5 MHz and pixels are addressed using a conventional matrix address scheme. Data are clocked into 16-bit shift registers positioned to the north and south of the array.
A digital 1 that scrolls down the east and west shift registers facilitates row enabling. Array update time is approximately 197 ms and the display can be driven in either an interlaced or noninterlaced mode. Each pixel contains a single transistor, metal row and column bus lines as well as a mirror that also functions as an electrode.
Philips Keeps Faith with UK Semiconductor Manufacture
Despite recent plant closures within the UK's semiconductor manufacturing industry, Netherlands contractor Philips Semiconductors is going ahead with plans to open its new PowerFab 2 fabrication facility in Hazel Grove, UK. Representing a $106 M investment, PowerFab 2 forms the latest element in the company's Hazel Grove power semiconductor competence centre and utilises submicron (0.8 mm) process techniques under class 10 clean room conditions.
Philips reports that the fab produced its first wafers within 67 days and has already achieved a 97 percent yield value. At full volume, the plant is expected to have a daily throughput of approximately 1700 150 mm wafers with an emphasis on the contractor's TrenchMOS technology. In the future, Philips' TOPFET2 process for the production of protected power devices for automotive applications is expected to be manufactured at the facility.
ASTOR Contractors Reveal Radar Sensor Details
The three contractor teams bidding for the UK's Airborne Stand-off Radar (ASTOR) contract have revealed additional information on the radar sensors they are proposing. UK contractor Racal Radar Defence Systems (RRDS) is developing an active, electronically scanned synthetic aperture radar/moving target indicator (SAR/MTI) sensor for use in the ASTOR solution being proposed by the Lockheed Martin UK Government Systems Ltd. consortium. The design utilises antenna-mounted transceiver modules developed by Raytheon Systems and employs an RF system based on the company's Searchwater 2000 series maritime surveillance radar. Digital signal generation and pulse compression are utilised and the radar's receiver/exciter is mounted onto the antenna array to optimise channel matching. The equipment's open-architecture signal processing chain utilises commercial off-the-shelf technology to reduce cost and risk. The necessary control and routing software is developed by RRDS, which is also responsible for the system's MTI algorithms. The radar's SAR algorithms are adapted from code developed by Lockheed Martin for a range of SAR sensors, including the Advanced SAR - 1 system used in the US Air Force's (USAF) SR-71A strategic reconnaissance aircraft. Motion compensation techniques used are based on those developed for use in the UK's ASTOR Technology Demonstration Programme.
The RRDS ASTOR radar is designed specifically to fulfill the UK's ASTOR requirement using low risk technology. However, the company is emphasising that its proposal also specifically addresses maintenance issues. In terms of a development cycle, RRDS reportedly is positioned to build production examples of its ASTOR radar immediately, has completed much of the necessary software validation and has test flown elements of the system.
The ASTOR consortium led by Raytheon Systems Ltd. (RSL) is offering an SAR/MTI radar sensor that is based on the company's ASARS-2 radar (operational aboard USAF U-2R and S high altitude reconnaissance aircraft) and incorporates technologies from the Hughes Integrated Surveillance and Reconnaissance and Global Hawk unmanned aerial vehicle radar programmes. The sensor's antenna and supporting electronic subsystems and software are being designed by GEC-Marconi Avionics Ltd. in a project that may amount to as much as 33 percent of workshare on the radar. Alongside GEC-Marconi, the UK's Defence Evaluation and Research Agency may be contributing its expertise in processing algorithms. Like RRDS, RSL maintains that its ASTOR proposal is fully compliant with the UK requirement and is stressing that, if it wins the competition, any follow-on ASTOR systems for export will be manufactured in the UK.
The remaining ASTOR solution is being offered by a consortium led by US contractor Northrop Grumman, which is proposing a radar sensor that utilises an electronically scanned antenna array and features a concurrent spot SAR and MTI operating mode. The sensor also incorporates an inverse SAR capability to facilitate high resolution imaging of moving ground targets. The radar incorporates the Advanced Radar Airborne Signal Processor (ARASP), which utilises commercial off-the-shelf circuit boards arranged in a massive parallel processor configuration to provide real-time processing of the sensor's output. The ARASP architecture contains more than 600 100 MHz processors and provides a peak throughput of more than 400 Gflop.
Northrop Grumman further claims that its proposed ASTOR radar incorporates a totally new-generation MTI classification mode. The radar sensor is a variant of the technology being offered to the USAF as a replacement for the current AN/APY-3 radar fitted to the service's E-8 Joint Surveillance Target Attack Radar System aircraft.