Sensitivity to Oil by Active Microwave Sensors

Abstract

Active microwave sensors are radars that operate in the microwave region (1 to 30 gigahertz in frequency, 1 to 30 centimeters in wavelength). Unlike passive microwave sensors, they provide their own illumination and do not depend upon ambient radiation. Microwaves propagate through clouds and rain with limited attenuation. Thus, active microwave sensors operate day or night, in all kinds of weather. Early radar systems involved a fixed radar source that scanned a field of view to track military targets, such as ships or airplanes. Current and proposed systems take many more forms and can operate as cameras, generating high-quality images from moving platforms. Research at Aerospace has been helping to advance the capabilities of microwave imaging and target-detection systems and expand their practical use. Reducing the risk of oil spill disasters is essential for protecting the environment and reducing economic losses. Oil spill surveillance constitutes an important component of oil spill disaster management. Advances in remote sensing technologies can help to identify parties potentially responsible for pollution and to identify minor spills before they cause widespread damage. Due to the large number of sensors currently available for oil spill surveillance, there is a need for a comprehensive overview and comparison of existing sensors. Specifically, this paper examines the characteristics and applications of different sensors. It also indicates on how the active microwave response can be used to detect oil. A better understanding of the strengths and weaknesses of oil spill surveillance sensors will improve the operational use of these sensors for oil spill response and contingency planning.