How the Saint Santin incoherent scatter system paved the way for a French involvement in EISCAT
- 1Bureau des longitudes, 23 Quai de Conti, 75006 Paris, France
- 2Ecrivain scientifique, 5 rue de la clef, 75005 Paris, France
- 3Institut de Planétologie et d'Astrophysique de Grenoble CNRS/UJF, 38000 Grenoble, France
- 4Acdémie des sciences de Paris, 23 Quai de Conti, 75006 Paris, France
- 5Institut Pierre-Simon Laplace, Université de Versailles Saint-Quentin-en-Yvelines, 78520 Guyancourt, France
Abstract. This paper relates the development of a French incoherent scatter system which started its operations in 1965. This development took place several years after the initial implementation of such systems in the United States, in Peru and in the United Kingdom. The French system, owing to its bistatic configuration and the use of continuous waves, differed from the previous ones. These characteristics yielded signals of excellent spectral quality, unravelling the possibility of inferring physical parameters (Doppler shift, average ion mass) out of reach, at that time, of other systems. The possibility of making ion drift vector measurements led to extend the system into a quadristatic configuration. The multiple capabilities offered by the incoherent scatter technique, notably as concerns the thermodynamical properties of the ionosphere and of the thermosphere, led further the French community to a project of embarking an incoherent scatter radar on board a ship. Taking account of a project of a Scandinavian auroral zone radar and of the considerable interest of the study of auroral zone electrodynamics, the French community abandoned the idea of the ship and expressed an interest in joining the Scandinavian project in conjunction with Germany and the United Kingdom.