European Communications Satellite Research Articles

Research on Spacecraft Integrated Electronic System Architecture Based on Information Fusion

This paper has designed the integrated electronic system and protocol architecture based on the standard of Consultative Committee for Space Data Systems (CCSDS) and European Communication Satellite System (ECSS). The application layer, application support layer, transport layer and sub network layer in the architecture can be described in detail, and the functions can be realized through the combination of various business and protocols. The architecture can provide technical support for the intellectualization and networking of spacecraft, standardize the spacecraft interface and protocol, it can promote the generalization of spacecraft equipment and software, and provide more flexible and powerful functions for the spacecraft.

A two-way time transfer experiment via ECS-1 using the MITREX modem

In the summer of 1986, a two-way time transfer experiment using pseudonoise coded signals was carried out between the Technical University of Graz, Austria, and the Fernmelde-technisches Zentralamt in Darmstadt, West Germany, via the European Communication Satellite ECS-1 operating in the 11-/14-GHz bands. Uncertainties on the order of 1 ns were obtained with Earth stations' EIRPs (effective isotropic radiated power) of 52 dBw, a G/T (gain-to-noise-temperature) of 22 dB/K, and sharing the satellite transponder with a television signal. The peak-to-peak fluctuations of the round-trip delays of the Earth stations turned out to be below 1 ns. >

Satellites for communications and broadcasting: The evolving european market

AbstractThe paper traces the development of the market for communications and direct broadcasting satellites in Europe, since the original specification of the European Communications Satellite (ECS) in 1977. It reviews the experiments undertaken on the Orbital Test Satellite (OTS) and the way in which demonstrations with this satellite have influenced the way in which ECS is being developed.It continues by considering the impact of television on the market, first cable television and its distribution requirements, then direct broadcasting by satellite, where the introduction of homes into the customer configuration will bring with it programme content as a salient feature in market development.Finally it speculates on the possibilities for the future, both in terms of the effect of new and higher frequencies on satellite communications systems, and the possible effects that interaction from small earth‐stations could have on satellite design.

A second-generation scpc system for business satellite communications

The European Telecommunications Administrations are planning to offer Business Satellite Services from the beginning of 1985. Designed under the auspices of EUTELSAT, the Satellite Multiservice System (SMS) operates in the 14/12.5 GHz bands and will use two satellites: the European Communications Satellite (ECS), and capacity leased on the French domestic satellite, Telecom 1. This paper describes the ECS SMS and in particular the Single Channel Per Carrier (SCPC) access system. This system operates over a range of data rates from 64 kbit/s to 2 Mbit/s and incorporates a number of novel features including satellite-link encryption, the use of soft-decision error correction, and full support of terrestrial interface standards.

14/11 GHz, 120 Mbit/s regenerative satellite transponder

This paper describes the design, implementation and performance of an experimental 14/11 GHz, 120 Mbit/s regenerative satellite transponder for possible use in the European communications satellite (ECS) system. Quarternary DPSK and CPSK are applied on the uplink and downlink, respectively. Demodulation and modulation are performed directly at RF. Specific components of the regenerative transponder, which are the pulse shaping filter, the differential demodulator, the baseband regenerator, the modulator and the output filter, were developed. Using the developed components, a laboratory model of the transponder was completed and evaluated. Bit-error-rate measurements were carried out with a test equipment simulating the earth terminals.

High-efficiency satellite antenna

A double cylindrical reflector satellite antenna of moderate directivity, and yielding an elliptical beamshape, developed for the European Communications Satellite System (ECS), is described, emphasising its high overall efficiency and applicability to other tasks which can exploit its inherent wide bandwidth.

Data transmission via European communications satellite

The European nuclear research centres of Cern, Desy, INFN/CNUCE, the Rutherford Laboratory and CEN Saclay are collaborating in an experimental computer network linked by OTS satellites. The paper describes the scope of the Stella experiment.

Satellite communications I: ESA at the crossroads: Projects for the 1980s at the space agency include satellite launches and a space platform

After a decade of national and transnational communications satellite programs, Europe is at the crossroads. It will move in this decade from the preoperational phase to the use of systems responding to its own needs. It is about to become competitive with the United States and Canada in this field. Five flight units of the European Communications Satellite are being built by European industry, with the first to be orbited by an Ariane launcher in October 1981. These satellites are to be used for carrying long-distance telephone traffic within Europe and for a television interchange service. In addition, ESA is committed to launching three maritime communications satellites. This decade will also see the development by European nations of a space platform that could hold a range of payloads for future communications needs.

The development of commercially available databases in Europe

The post‐war database revolution was triggered by ‘missions’ like health and nucleonics. In the last 10 years, the emphasis in databases has shifted from science and technology to business and softer disciplines, and from files of references (bibliographic files) to files of information (data banks). While Europe has outstripped the rest of the world in the number of bibliographic files, she lags behind in data banks and online availability. To get out of our information impasse we need to make intelligent use of new technologies like Viewdata and the European Communication Satellite, and find new ‘missions’.

Propagation experiments at 11/14 GHz as part of the European communications satellite program

A Comprehensive program of propagation measurements is being carried out in Europe in connection with the planning of a regional satellite communication system for operation at 11/14 GHz. Statistics of atmospheric attenuation are collected by means of static radiometers and the feasibiity of frequency reuse techniques by polarization discrimination is investigated on several point-to-point links using both linear and circular polarizations. The results obtained so far are outlined and the use that is made of them in designing satellite systems is discussed.

Attitude Stability of SYMPHONIE-Theory and Flight Results

Symphonie is the first European communications satellite. It has some peculiarities that distinguish it from other geosynchronous satellites: its apogee boost motor uses liquid propellants during the operational phase it is three-axis-stabilized. These points pose some special problems with regard to attitude stability. A number of theoretical investigations were performed to analyse these stability problems. Their results are summarized and are compared with the flight results obtained from the two flight models in orbit.

Space for the Open University

In the first- part of this paper the Open University is considered as a case study of a large-scale producer of educational materials at university level, including those for dissemination to mass audiences. The paper continues as a discussion of the place and purposes of broadcasting and alternative delivery techniques within the University’s integrated multi-media instructional system. Some of the problems of using these techniques are identified. The final section is a speculation on the possibilities of using a British or European communications satellite for mass higher education on the lines of the Open University model.

Drag coefficients for astronomical observatory satellites

The first experimental European communications satellite Symphonie is a geostationary satellite. The satellite is designed and built in a joint project by French and German aerospace firms. A description is given of the basic technical concept of the satellite. The apogee motor is discussed along with the satellite stabilization system. The stabilization system provides a three-axis positional stabilization and an orbital stabilization. Attention is given to the spin stabilization phase, the sensors employed, the approache used for orbital correction maneuvers, and the conduction of simulation tests on the ground.

Transmission of 4Ø-Phase-Shift Keyed Time-Division Multiple Access over Satellite Channels

The design of 60 Mbit/s/180 Mbit/s time-division multiple-access (TDMA) channels for the European Communication Satellite (ECS) system is analyzed and a possible configuration is suggested [1]. The effects of adjacent-channel interference, nonlinear power amplifiers both on the ground and in space, uplink and downlink noise are investigated and results are shown. Methods for carrier recovery are investigated and comparisons made. The complete channel design includes pulse-shaping filters, satellite filters, limiters before each TWT, and a filter after the earth-station TWT to limit the radiated spectrum.

Proposed European communication satellite system

The paper describes the derivation of the basic parameters of a European regional communication satellite system. The derivation involves optimisation of satellite antenna beamwidths and transponder bandwidths with respect to the expected traffic demands for the decade 1980 to 1990. Ground-station-sensitivity optimisation to achieve minimum overall system cost is described. Frequency reuse by the application of dual-polarisation transmission is briefly examined as a means of increasing system traffic capacity.