Real time passive mm-wave imaging

This paper discusses the issues that need to be addressed in the design and development of real time millimetre wave(MMW) imaging systems. The advantage offered by MMW imagers under adverse weather conditions are considered as are their thermal and spatial resolution. It is shown that it is difficult to use fully integrated focal plane arrays of receivers in large aperture high performance systems since the focal plane is so large. Instead scanned systems are considered to be preferable. Mechanical and electronic scanning techniques are described as is the use of image processing techniques which may increase the sharpness of an image by up to a factor of four. The paper introduces a new figure of merit for image quality which can be used to compare imaging systems.