Altimetry in the Cassini Mission

The main purpose of the Cassini Mission is the investigation of the geomorphologic structure of Titan, the most interesting moon of the Saturnian system. Titan is completely covered by a dense atmosphere that prevents optical observation. A spacecraft will be launched toward Saturn in 1997. The spacecraft will be equipped with microwave instruments. A multimode radar is one of these instruments and it may operate in altimeter mode. This paper deals with an overview of the design and performance of the altimeter and discusses some different scattering models and their application in the different operative modes of the Cassini altimeter.