摘要
利用Nd：YAG 激光器产生10 Hz 的1064、532 和355 nm 激光束作为光源，研制了用于对流层大气气溶胶探测的全天时多波长激光雷达，实现了溶胶Mie散射信号在紫外、可见和红外三个波段的精细分离和提取。通过小孔光阑和窄带干涉滤光片对背景光的强烈抑制，实现了全天时探测。通过对三波长Mie 散射信号日间和夜间探测信噪比数值仿真和实际探测信噪比分析，得出日间探测时532 nm 的信噪比最低，夜间探测时355 nm 的信噪比最低，这与数值仿真结果一致。通过分析实际探测信噪比为1时的数据，得到该系统日间探测高度可达8~10 km，夜间探测高度可达10~12 km。对西安地区晴天、多云天和雾霾天的初步探测结果表明，该多波长激光雷达的性能完全能够满足对流层内气溶胶粒子的全天时和不同天气情况下的探测要求。
An all time multi-wavelength lidar system used for the detection of troposphere atmospheric aerosols is developed. It utilizes the beams of 1064, 532 and 355 nm emitted by a Nd：YAG laser at the frequency of 10 Hz. This multi-wavelength lidar realizes the precise separation and extraction of Mie scattering signal at ultraviolet, visible and infrared wavelengths. The sky background noise is strongly restrained by using aperture and interference filters, and the all time detection is achieved. The signal to noise ratios （SNR） of actual detection results are compared with simulation results at three wavelengths. It is found that the SNR at 532 nm is the lowest in the daytime detection; however, the SNR at 355 nm is the lowest in the nighttime detection. This result is consistent with the theoretical calculation. The detection height can reach 8~10 km in the daytime and 10~12 km in the nighttime, providing the actual detection SNR is 1. The results of actual detection in Xi′an in fine, cloudy and haze days show that the multiwavelength lidar can fully satisfy the need for detection of troposphere atmospheric aerosol particles at all time and under various weather conditions.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2015年第1期276-283,共8页
Chinese Journal of Lasers
基金
国家自然科学基金(61168004)
宁夏回族自治区自然科学基金(NZ14099)
关键词
大气光学
多波长激光雷达
信噪比
气溶胶
MIE散射
atmospheric optics
multi-wavelength lidar
signal to noise ratio
aerosol
Mie scattering
