Design of a distributed aperture millimeter-wave imaging system for 'see-through' imaging in rotary craft induced degraded visual environments

摘要

The demand for all-weather, day-night imaging systems has been spurred by calls for persistent surveillance in security and defense applications, and increased safety in military aviation, such as carrier landings in fog and helicopter landings in sand and dust. To meet these demands requires systems that offer robust imaging capabilities. Whereas visible and infrared systems can provide high resolution imagery in a small-sized package, they are hindered by atmospheric obscurants, such as cloud cover, fog, smoke, rain, sand, and dust storms. Millimeter wavelengths, on the other hand, are not and passive millimeter wave imaging may be one method to reduce, or perhaps even eliminate, the impact of low visibility atmospheric conditions. In this paper we examine the scattering from rotorcraft induced dust clouds using Sandblaster dust particle density data. We examine the effect of Mie scattering as a function of particle size and operating wavelength and conclude that W-band operation yields the highest resolution imaging while still maintaining "see-through" imaging capability.