Study of Earth Observation by Frequency Scanning. Volume 1. Executive Summary

摘要

Microwave remote sensing from space necessitates instruments to operate under severe constraints. One method of reducing the demands of power and mechanical complexity is to improve the antenna directivity and steer the beam electrically. Frequency scanning provides a simple and elegant means of using frequency to control the antenna beam direction. It enables the beam to be steered rapidly in space without moving large mechanical masses and more efficiently utilises the available r.f. power directing it more precisely to the region of interest. In comparison with active inertiales scanning techniques, frequency scanning is simple and reliable and hence particularly attractive for spaceborne sensors. This study is aimed at exploring the potential of frequency scanning as a technique for reducing the demand of microwave remote sensing instruments on the resources of the spacecraft. The applications for investigation are Scatterometry and imaging Radiometry.