Abstract

In satellite communications systems utilizing automatic power control and/or polarization compensation networks, a knowledge of instantaneous area rainfall information is essential. This knowledge cannot be supplied by a conventional tipping bucket rain gauge, which has a slow response and a low saturation level. The paper examines laser sensing techniques for the development of a high precision/fast resolution rain gauge using an HeNe laser. Optical configurations, detection schemes and data acquisition and processing algorithms are presented. Preliminary field trial results in determining instantaneous rain rates and raindrop size distributions are summarized. It is established that such an optical system can sample precipitation accurately, not only in the far field region, but also in the near field. Applications in modern satellite communications systems are outlined.