Frequency use and needs of spaceborne active sensors

Spaceborne active sensors have been used for several years to study the Earth's surface and atmosphere. The intent of this paper is to present the unique types of sensors and their characteristics that determine their individual frequency needs; to present performance and interference criteria necessary for compatibility studies with other services in the frequency bands of interest; and to present a status of current frequency spectrum use and needs and compatibility studies of spaceborne active sensors and other services, along with any issues or concerns.