Satellite technology


Astra is the most important satellite position for German-speaking countries (19.2° East). The operator of the ASTRA satellites is SES (Societe Europeenne des Satellites), founded in 1985, Europe’s first private satellite operator in Luxembourg. Three years later, on 11.12.1988, the first ASTRA satellite, Astra 1A, was launched into orbit. The company is based in Betzdorf/Luxembourg, where the ground station is also located, from where the television signals are transmitted to the satellites. These signals are converted by the satellites, amplified and then sent back to earth. In 1996, commercial digital television via satellite was introduced and since 1998, SES has had a second orbital position at 28.2° East to provide sufficient capacity. Today, there are seven satellites at 19.2° East and three satellites at 28.2° East. In the final expansion phase, up to 8 satellites will be co-located at each position.


EUTELSAT is a transnational organisation formally established in 1977 by the European Conference of Postal and Telecommunications Administrations. The EUTELSAT organisation received its definitive status in 1985. In June 1983, the first Eutelsat I F1 satellite was launched into space. Today, the EUTELSAT Organisation operates ten satellites in addition to the best-known satellites Hotbird 1-5 and has also acquired a licence for a second orbital position.


In order to provide the maximum reception power to the customers of the satellite operating companies, only these countries are supplied with satellite programmes – as far as this is technically possible. The coverage of these areas is represented by the so-called footprints. History of satellite technology The satellite era began on 4 October 1957, when the first artificial Earth satellite, Sputnik 1, was launched into orbit. In 1983, the first television satellite went into operation over Europe. Today, about 30 satellites supply Europe with television and radio programmes. Today’s satellites weigh up to 4 tonnes. They function like a giant amplifier in the sky and have a total power consumption of up to 7000 W. In order to supply the satellites with the necessary energy during the eclipse periods (periods of darkness), the solar generators and the batteries are designed in such a way that sufficient power is available for the payload all year round. There are five manufacturers of telecommunication satellites worldwide. The construction of a satellite takes about three years. Extensive testing during the manufacturing process ensures that the satellites function perfectly in space.The lifetime of a satellite is usually limited to about 12 years. During this operating time, it is constantly monitored by the ground station and held in position via control jets. Therefore, the useful life ends when the fuel supply of the satellite runs out. With the last remaining fuel, the satellite is catapulted out of its orbit and is thus lost to the operator.

KO positioning

KO-positioning means that several satellites are parked on one position. This parking position represents a cube of 70 km edge length in which several satellites move without contact. The satellites are held in this transmitting AutoSat 2S window via the control nozzles.

Position of the satellites

The satellites are positioned on a geostationary orbit at an altitude of about 36 000 km above the equator

Transmitting power

The transmitting power is 45 W – 130 W per transponder


The satellites have up to 32 transponders. Up to 10 digital television channels can be transmitted on one transponder.

Transmission method, analogue technology

The analogue transmission method was the standard in the past. The disadvantage of this technology is that an entire transponder is needed to transmit one television programme, whereas with digital transmission up to 10 television programmes are needed. Analogue transmission of radio and television programmes was discontinued in 2012. However, this is not a problem for analogue AutoSat 2 and analogue AutoSat light systems, as they can be converted without any problems.

Transmission methods, digital technology

The latest standard in digital transmission is high-definition television, or HD for short, or DVB-S2. This standard will become increasingly important for the transmission of television, radio programmes and multimedia services. All AutoSat systems are optimally equipped for the future.

Requirements for satellite reception

To achieve perfect reception of satellite channels, four factors must be taken into account: Antenna size, unobstructed view of the satellite, suitable reception equipment and the right know-how when searching for satellites:

Antenna size

An important criterion is the antenna size, it determines the reception range whether they are in the reception area can be checked with the footprints of the individual satellites. The range is severely affected by poor LNBs or inferior mirrors.

Clear view of the satellite

The view to the satellite must be free of obstacles Trees or buildings impair or completely prevent reception. Geographical conditions can also prevent the reception of satellite signals. Especially in the far north, obstacles at considerable distances (mountains, hills) can prevent reception of satellite programmes due to the curvature of the earth.


Other prerequisites for reception are suitable reception equipment, such as a universal LNB, analogue receiver, DVB receiver (digital), DVB/CI receiver or decoder for receiving the desired TV programmes.


DVB stands for Digital Video Broadcasting (digital television). Behind it is an organisation that has set itself the task of creating standards for the transmission of digital picture content.


DVB/CI refers to the connection of free-to-air programmes and the possibility of receiving encrypted pay-TV programmes. In addition to the CI interface (common interface), a CA module (conditional access module) and a smart card are required for this.

CI interface

In order to be able to receive several different pay-TV packages, which use different encryption systems, with a single receiver, there are two different technical solutions according to the DVB standard: The Simulcrypt procedure and the Common Interface (CI) The Common Interface has become the accepted standard and is supported by almost all receiver manufacturers. The required CA module can be plugged into this standardised interface in PCMCIA type II format. This means that different pay-TV bouquets can be received with one receiver. Many TV programmes or additional offers are broadcast in encrypted form on digital TV. The use of these programmes is subject to a fee. To be able to receive these programmes, you need a corresponding decoding system. This can be done by means of a specially designed set-top box (e.g. Premiere) or by means of a CA module which is inserted into the CI slot of a set-top box. The CI is a universal interface which allows non-discriminatory access to all pay-TV programmes. The CA module (Conditional Access module) Since different encryption codes are used by the individual broadcasters, the viewer must have a separate CA module for each code type. The possibility of being able to decrypt different codes with the help of exchangeable CA modules is known as the multicrypt method. In addition to the corresponding CA module, the viewer also needs a personal authorisation card (smart card) to activate the programme. The purchase of such a smart card is subject to a fee and to certain national regulations (place of residence, citizenship).

Satellite search know-how

Besides searching and finding the satellite, the most important criterion for a well-functioning automatic satellite system is setting it to the best picture. Some satellite systems perform the satellite search and optimisation with the help of the reception field strength. However, this cannot always be used as a clear indication of the reception of satellite signals or for setting a good picture. This is not the case, however, with AutoSat systems: These carry out a verification of the satellite and optimise the best reception based on the picture content.