Airport, The Reflective Properties Of The Launch Site Clouds Laser

The meteorological observation of airport and launching site is the important prerequisite of blastoff of spacecraft and aircraft. Meteorology observation, especially cloud observation is comparative direct, efficient, and accurate with lidar. Analysis of laser scattering character of cloud layer is the theoretical basis of meteorology observation with lidar.The purpose, significance and studies by other scholars in the similar field are briefly introduced in the introduction. After that, theories of cloud measure with lidar are discussed, including atmospheric physical theory, principles of light scattering, and groundwork of lidar. In Chapter Three, we quantitatively analyze wavelength of laser that detect cloud layer, and have found optimum laser wavelength value according to Mie scattering theory in atmospheric optics. We get rules of the attenuation of fog, cloud, haze and atmosphere as the height changes, and give the calculation formula of the laser scattering character of cloud layer. In Chapter Four, laser scattering character of cloud layer is simulated with computer under different meteorological conditions. Through simulation we have got four conclusions, which are presented in details in Chapter Five, (l) We can distinguish the accurate and visual height of normal cloud and thin cloud layer because the backscatter signal of cloud is much stronger than the backscatter signal of normal atmosphere. If laser can pass through multi-layer cloud, we can also judge the number of layers and the thickness of cloud directly. (2) Backscattering signal features of different clouds can be completely identical, so we can judge the height of cloud base and thickness of cloud from only one analysis of scattering signal. However, we cannot judge the kind of cloud layer accurately at one time. (3) We need to scan the cloud to a crumb along different angles, get the three-dimensional block figure, and compare figure with the features of different kinds of cloud to get the category of cloud. (4) We can also distinguish fog and the solid barrier which is in the direction of laser spread route.The theoretical research in this thesis will be the theoretical foundation and technical request for the design and manufacture of lidar ceilometer...