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Airborne 3-D focal imaging LiDAR can take images in a very short gating time (3~5ns), so it can shield background noise instantaneously. Since the area of laser irradiated surface is about when the detected distance is about 3km, to ensure high imaging quality the laser beam needs to be smoothed before it arrives the ground. In this paper, based on self-developed airborne 3-D focal imaging LiDAR system, a beam homogenization device by using lens array method is presented for the detection range from 1km to 3km. The experimental result indicates that the smoothing rate can reach 89%. Subsequent tests in LiDAR system show that the homogenization device is reliable and effective.

The AEDAL (Atmospheric Environment Detecting Airborne Lidar) operating at the 532nm Nd: YAG wavelength was flown aboard the China Monitoring of Sea (CMS) 3807 over Qingdao and adjacent sea area. The primary aims of this platform were to prove the capability to develop airborne lidar is available in our country, meanwhile, get the spatial and temporal variation of the atmosphere boundary layer (ABL) and aerosol distribution along flight lines. In order to investigate the effect of topography on the ABL and aerosol distribution, various terrains were included under the predetermined flight lines. The comparison of the AEDAL results on the 8 and 11 November shows that the spatial and temporal variation of the ABL and the aerosol distribution are impacted by meterorolgical factors such as temperature, humidity, pressure, wind, and even terrain feature.

A new kind of lidar signal light-splitting system is presented to sum up different rotational Raman lines and to improve the signal to noise ratio (SNR). The temperature parameters with high SNR of this new system have been obtained with a normal laser and a small telescope from several kilometers.

Anthropogenic emissions of CO2 over the past century have altered significantly the climate over the global. Using Lidar system to detect the atmospheric carbon dioxide is a novel and efficient technique. The cybernation process of Lidar system accomplish the energy monitoring, acquiring controlling, photon counter controlling and signal disposal and display controlling. In this article, the auto-control processes are described in detail. Moreover, the principle of the Lidar controlling is introduced. We use the computer to manage the energy meter, select the appropriate filters and attenuation mirrors by controlling the step motor, run the software to acquire the amplified backscatter signals. At the same time, the cybernation process analyzes the recorded signal and displays the ultimate results. In addition, the cybernation process has been applied into the Lidar system and achieved successfully the concentration profiles of the atmospheric carbon dioxide.

Lower tropospheric water vapor measurements are performed at nighttime using the mobile atmosphere monitoring lidar-2 (AML-2) which is operated by the Anhui Institute of Optics and Fine Mechanics. In this lidar system, a 354.7-nm light from a Nd:YAG laser is used as stimulating source, whose Raman shifted center wavelengths are at 386.7 and 407.5 nm for nitrogen and water vapor, respectively. We present a novel and convenient method for determining the Raman lidar calibration constant according to the scanning performance of this lidar. We are likewise able to realize the measurement of water vapor profile in the low troposphere. The error induced by the uncertainty of calibrated constants is within 7% for the Raman lidar system. Experimental results from two months of study indicate that the method of calibrating the lidar system constant is feasible, and the Raman lidar performance is stable and reliable.