Performance Analysis of Doppler Lidar

点击翻译按钮获取中文摘要

9307233 Frehlich Research is proposed to analyze the performance of Doppler lidar for real system configurations, including the effects of refrctive turbulence and detector geometry. System performane is determined by the Signal to Noise Ratio(SNR) and the heterodyne efficiency. Analytic and numerical calculations of SNR and heterodyne efficiency for real and idealized Doppler lidar systems will be performed. The statistical behavior of estimates for heterodyne effciency will be determined for single element and multi-element detectors. The use of multi-element detectors for improving system performance when refractive turbulence is important will be investigated theoretically and with numerical simulations. The simulations will also produce accurate statistical description of real Doppler lidar signal fluctuations due to the random aerosol targets and refractive turbulence. The different physical mechanisms of Doppler lidar performance will be investigated and the regimes where simple analytic results are valid will be determined. The calculations will emphasize the shorter wavelenghts of solid state lidar systems. The effects of wind variations in the sensing volume of Doppler lidar will be determined theoretically for realistic atmospheric conditions. New data analysis techniques will be applied to Doppler lidar data to verify the theoretical results and produce accurate estimates of the atomospheric decorrelation time for Doppler lidar signals. This is essential for evaluating the accuracy of Doppler Lidar velocity estimates. The performace of Doppler Lidar velocity estimation for various wavelengths and system designs will be determined using the theoretical results of the atmospheric decorrelation calculations and the experimental measurements. This research will help design the next generation of solid state Doppler lidars for remote sensing of the atmosphere. ***