Active Imaging at DARPA

by J. C. Ricklin & P. G. Tomlinson

Proceedings of SPIE 5895, 2005

Active systems, because they provide their own illumination, are capable of operating 24 hours a day and are not dependent upon the angle of the sun. Unlike passive systems, they can provide three-dimensional imaging. DARPA is currently developing systems, technologies, and signal processing to pioneer new or improve existing capabilities that employ active imaging capabilities. These involve both radar and ladar, ranging from a few MHz for foliage penetration to near-visible IR to achieve ultra-high resolution at long range. These capabilities would improve Battlefield Awareness and provide persistent Intelligence, Surveillance, and Reconnaissance to perform target detection, recognition, and identification. This paper discusses two different approaches to active optical imaging. One is a coherent approach that uses synthetic aperture techniques with infrared laser radar, and another approach uses only the intensity of the speckle pattern in the aperture plane. Both are capable of producing ultra-high resolution at long range. Read more