- Buyers Guide
Wins Europe's Largest TV Uplink Earth Station The Franco-British Matra Marconi Space consortium has been awarded a multimillion-pound contract to provide British Sky Broadcasting (BSkyB) with Europe's largest television uplink earth station. To be located at Chilworth in the UK, the new facility will provide up to 200 digitally compressed television channels and support BSkyB's 14 satellite transponders aboard the ASTRA 2A broadcast satellite, which is scheduled for deployment at 28.2° East this fall. This initial tranche of transponders will provide the company with up to 100 digitally compressed channels.
The Chilworth site comprises two 8.1 m antenna systems (with automatic tracking and de-icing capabilities) and a full suite of necessary electronic communications subsystems. The station will operate in the 11 to 12 GHz band for reception and the 17 to 18 GHz band for transmission. The antenna system used will be fed by 16 klystron power amplifiers (expandable to 24 if required) and four standby traveling-wave tube amplifier (TWTA) subsystems. Each subsystem comprises two TWTAs in a phase-combined configuration. The station's transmission subsystems will be supported by downlink monitoring and test facilities together with Matra Marconi's proprietary earth station control and monitoring tool.
Philips Relies on New Process for Wideband RF Transistor Production
Netherland's contractor Philips Semiconductors is relying on a new company-developed double-polysilicon fabrication process for the manufacture of a new generation of high gain, small-signal transistors for use in the front-end receiver sections of 3 V mobile telephones. To facilitate the process, the company has invested $15 M in dedicated equipment for its wafer fabrication at Nijmegen, the Netherlands.
In general terms, polysilicon is a layer of poly-crystalline silicon that is deposited onto semiconductor wafers by the low pressure chemical vapour deposition process. Because this approach is self-aligning and allows for precise thicknesses of silicon to be grown over underlying layers of silicon or silicon dioxide, it can be used to create vertical transistor structures with controlled geometries. The term double-polysilicon refers to Philips' use of two discrete layers of polysilicon in its new-generation RF devices where polysilicon is used for the base and emitter connections to provide base widths of 100 nm and cutoff frequencies of 25 GHz. Rapid thermal annealing of the implant dopants in the first layer of epitaxial polysilicon is used to generate the doping profiles in the base and emitter regions, which are necessary to create the narrow base bandwidths needed for the cited cutoff frequency. The process also provides the submicron emitter widths (typically 0.5 mm) needed to ensure low base resistivity for the less than 1.2 dB noise figure requirement in low noise applications.
DE to Supply RWR to the French Army's Air Corps
French defence electronics contractor Dassault Electronique (DE) has been awarded a substantial order for its EWR-99 radar-warning receiver (RWR) for use on French army aviation Puma, Cougar and Gazelle helicopters. This latest contract follows an earlier crash programme under which the equipment was installed on French helicopters being deployed to Bosnia. According to DE, the 6.4 kg EWR-99 is effective against continuous-wave, pulse and pulse-Doppler emitters operating within a wide frequency range. The device uses extensive miniaturisation and a database-oriented, programmable system that incorporates both threat-warning and countermeasures-control capabilities. Other features include built-in test, night vision goggle compatibility, interoperability with a missile-approach warner and a data-recording interface for the capture of threat information for postmission analysis. France Snubs GEC Thomson-CSF Bid
In a surprise move, UK defence electronics contractor GEC-Marconi has made an outright bid for France's Thomson-CSF, the military arm of the Thomson electronics group, which is being privatised currently by the French government. Reportedly, initial discussion between GEC and the French authorities encouraged the bid, which was rejected on grounds of national interest. A GEC-Marconi spokesman notes that while the rejection is a disappointment, the company has gone on to open negotiations with French contractors Alcatel and Lagardere in hopes of joining one of them in their respective bids for the company. The Thomson bid is only one of a number of opportunities GEC is exploring in an ongoing effort to develop its position as a world leader in defence electronics. In related news, the company is also interested in acquiring all or part of German contractor Siemens' defence interests and in opening negotiations with US giant Lockheed Martin to form some sort of trans-Atlantic industrial alliance. UK business analysts suggest that any deal with Lockheed Martin will not involve cross shareholdings or a full-blown joint venture but rather will represent a marketing agreement that will provide the two companies with enhanced access to each other's markets in specific business sectors. Such a deal may also allow GEC to pursue other alliances such as a tie-up with UK aerospace contractor British Aerospace.
Angola Implements Improved Communications Infrastructure
In the wake of its long-running civil war, Angola has initiated a communications infrastructure improvement programme using ruggedised mobile telephone exchanges and more than 500 telephone units to be supplied by UK contractor Racal Acoustics. At the heart of the new system (which will be used to replace equipment destroyed during the fighting) is the company's RA2135 automatic, tactical private automatic branch exchange system, which offers voice and data capabilities in extreme climatic conditions. Each exchange can support up to 120 subscribers and/or 12 external lines. The unit has a capacity for up to 16 plug-in modules, which can be a combination of subscriber (eight subscribers per card) and connection (four lines per card) cards. Up to 16 circuits can be produced at any time. Other system features include preprogramming of facilities for each extension, the ability to support battery and magneto telephones, call transfer and call back/no reply, call hold, call pickup, call forward and direct dial for subscribers designated as category A users. SPS to Supply
UK Military SATCOM SystemUK contractor Siemens Plessey Systems (SPS) has been awarded a £10 M contract to supply the UK Ministry of Defence with 10 satellite field terminals (STF) and support facilities to meet the UK/TSC503 system requirement for a high capacity, secure communications capability for use by the country's armed forces worldwide. SPS describes the UK/TSC503 STFs as modular in design to allow the user to deploy the equipment in a variety of mission-specific configurations. The equipment is transportable (using ruggedised transit cases) and features a 2 m antenna for rapid deployment scenarios together with a 4 m array where a high capacity link is required.
The new program involves extensive environmental testing and type qualification. The first four units are scheduled for delivery by November 1998 with the remaining four to be supplied by May 1999. SPS anticipates further orders for an additional 10 STF systems.