Symphonie

The Symphonie satellites were the first communications satellites built by France and Germany (and the first to use three-axis stabilization in geostationary orbit with a bipropellant propulsion system) to provide geostationary orbit injection and station-keeping during their operational lifetime. After the launch of the second flight model, they comprised the first complete telecommunications satellite system (including an on-orbit spare and a dedicated ground control segment). They were the result of a program of formal cooperation between France and Germany.

Within the bilateral (CNES – GfW) French-German contract, and under industrial prime contractorship of the CIFAS consortium (which was a European economic interest grouping under French law) composed of six companies (three French and three German), their responsibilities were as follows:

Symphonie-A was successfully launched from the Kennedy Space Center on December 19, 1974, at 2:39 a.m. UT.

Symphonie was the forerunner for numerous telecommunications services. Its prohibition on commercial use may have paradoxically induced a larger program for experimentation of space telecommunications than ever before – both in the number of participating countries and diversity of field applications. As an example of the extent of its use, 40 countries participated in links via Symphonie A and B (east-west and north-south) – from Quebec to Argentina, from Finland to Reunion Island and from China to Indonesia. The Symphonie A and B experiments may be divided into two types:

To these types operational experiments may be added, notably for links between metropolitan France and its overseas departments for telephony and television via satellite. From this viewpoint Symphonie was a forerunner of the French national programs Telecom-1 & 2 and TDF 1 & 2, and the German programs TV-SAT and DFS Kopernikus. The wideband transponders, with their operational flexibility, made it possible to test all-access techniques (single or multiple) and modulation: FDMA (frequency sharing), TDMA (time sharing) and SSMA (spread spectrum). Symphonie terrestrial stations with antennas of various diameters from 16 to 2.2 meters (fixed, portable and mobile) contributed to the renown of the programme around the world. Several demonstrations were:

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