Evolution of Spaceborne SAR Missions in Earth Orbit

A truly operational SAR was first flown in space in 1978 on board the Seasat satellite. Since then, its utilization first expanded to Canada, Europe and Japan, and then to countries with emerging space industries later on. Many technological developments have been crucial in the evolution of SAR missions. The introduction of active phased array antennas enabled a variety of operation modes and expanded SAR data applications. Miniaturization of satellite technology allowed for a paradigm change in SAR mission development with the use of small and micro satellites in lieu of large spacecraft. The paper reviews 47 years of SAR missions in low Earth orbit and highlights evolution trends by analyzing 200 satellites.