The 2D-Video-Distrometer

Abstract

Detailed knowledge on tropospheric precipitation microstructure is one of the bases in various fields of sciences and applications, like terrestrial and satellite radio transmission, remote sensing of precipitation, generally tropospheric wave propagation and atmospheric sciences. In the field of telecommunications, precipitation causes several unwanted effects on Earth-satellite as well as on terrestrial links. System design has to consider that and has to take care for appropriate countermeasures. Statistical approaches allow quantitative answers on questions about precipitations impact on wave propagation. Thus probabilities are given, that e.g., rain induced attenuation or phase delay exceeds a certain threshold for a given set of parameters (location, frequency etc.). Increasingly demanding applications (higher frequencies, frequency re-use and multiple satellite links) require answers on increasingly complex questions. Remote sensing technologies aim at measuring precipitation parameters at far distances, using either spaceborne or ground-based radars and radiometers. Such observations permit better climatological characterization, on a global as well as on a regional scale. Global keyword terms like greenhouse effect, global atmospheric warming, tropical rainfall, the Earths energy and water cycle, etc. immediately indicate the urgent need for such observations. Speaking in local scale, short-term climatological considerations play a more important role. Weather fore- and nowcasting help in many various ways in everyday life. To mention only but a few examples of the numerous points of interest: flood and storm warnings, control of air and road traffic, control of hydroelectric power plants, water resources management, etc.