Millimeter wave imaging sensors, sources and systems

摘要

A millimeter wave imaging system is disclosed which has wide applicability throughout transportation and related industries. For example, the system may be used to provide an aircraft pilot with an image of a landing field which is essentially unaffected by fog, rain, snow, blowing sand, etc. The system comprises an array of imaging elements as its fundamental component. Each of the imaging elements of the basic array comprises an antenna consisting of a pair of conductive elements and a non-linear circuit element connected thereacross. A image can then be formed responsive to millimeter-wave radiation without complex processing steps or any form of mechanical or electronic scanning. To increase the sensitivity of the imaging array system, a local oscillator signal may be mixed with the energy received from the field of view in each of the imaging elements by the non-linear circuit element. The oscillator used to provide the local oscillator signal can also be used to illuminate the field of view. Coded beacons emitting encoded millimeter wave energy for detection by the imaging array may also be employed.