Based On The Dual-edge Technology Doppler Wind Lidar System Design

Since the lidar appeared in 60's, this technique got rapid development within 40 years, and its application field is broadly expended, involving science research, the military engineering and many parts of national economy. Especially, it show the outstanding development foreground in the atmosphere measure.Doppler lidar can acquire the atmosphere wind field of the high altitude and time resolution, it is only valid method that had be proved to accurately measure global three-degree wind field. Doppler lidar mainly includes coherent detection and direct-detection techniques. Although coherent detection Doppler lidar have high sensitivity and high measure precision. It was used only aerosol-based in the atmosphere, and its scope and the ability was limited. Direct-detection Doppler lidar technique has advantages comparing to coherent technique.This dissertation describes the background of the subject and the application's value, gives the development of Doppler lidar wind measurement, introduces the system specification and technique courses, illuminates the designing and equipment election of system and the subsystem; mainly introduces the theory and methodology of the double-edge technique based on the Fabry-Perot etalon and the algorithms of lidar data processing.During the process of dissertation, reference specification of the foreign of the same kind product was used. Combined the domestic actuality, system specification was presented. The direct-detection technique's characteristic included: simple systematic structure, low demand to laser frequency stability. It has ability to analyze the aerosol and molecular backscatter signal, actualize observation of the wind field in the global scope(big space scope). The theory and methodology of the edge technique for high-accuracy wind measurement was used direct-detection lidar with aerosol-based and molecular-based. The double-edge technique used two edges with opposite slopes symmetrically located about the laser frequency, and the laser is located at approximately the half-width of each filter. A Doppler shift would produce a positive change in signal for one edge filter, with respect to its initial position. For the other edge, the corresponding signal change was opposite in sign and approximately equal in magnitude for filters with the same properties. Thus the signal change was doubled for a given Doppler shift which yields improved accuracy 1.6 times compared with the single-edge technique .In this dissertation, author took the responsibility of reasoning the project and system designing, analyzing the system performance, structure designing. The most important was optics receiver's design and the algorithm of lidar data processing based on Fabry-Perot etalon's study.