INFRARED RADIOMETER APPARATUS FOR DETECTING CLEAR-AIR TURBULENCE FROM AN AIRCRAFT

摘要

A radiometer apparatus suitable for use on a supersonic aircraft for clear-air turbulence detection includes means for operating at four selected wavelengths within an atmospheric absorption band, for example the 15 mu band of carbon dioxide. At any particular height of the aircraft each of a set of filters used to select the four selected wavelengths has a weighting function which depends on the effective absorption coefficient of the atmosphere at that wavelength and each indicates which part of the atmosphere ahead provides a significant contribution to the radiation measured by the apparatus. At longer wavelengths the atmosphere is opaque and the radiometer apparatus receives radiation from immediately in front of the aircraft. By generating suitable functions from the outputs of radiation passed by two or more of the filters it is possible to detect turbulence of the type looked for.