摘要
直接探测多普勒测风激光雷达中,双边缘技术可分别测量回波信号中大气分子散射和气溶胶散射的成分,因而在保持高测速灵敏度的同时,可以减小瑞利背景噪声的影响。这决定了其在大气对流层风场观测的优势地位。直接探测双边缘技术中,使用双通道 Fabry-Perot 标准具作为鉴频器,将频率变换转换为信号强度变化。该技术的前提是出射激光频率始终处在双通道标准具透过率曲线的交点频率附近。提出的标准具腔长调制反馈电路方法有效解决了该问题。
A stabilizing circuitry is designed to modulate the cavity of the Fabry-Perot interferometer with respect to a reference frequency,while simultaneously keep the parallelism of the reflecting flats.Double-edge technique allows the Rayleigh and aerosol components of the backscattered signal to be independently determined while keeping high measuring sensitivity.These advantages make it become a popular method in wind observation in troposphere and low stratosphere.The double-edge technique uses two edges with opposite slopes symmetrically located near the laser frequency,so the Fabry-Perot etalon as a frequency discriminator transforms the Doppler frequency information into intensity changes of the signal.
出处
《红外与激光工程》
EI
CSCD
北大核心
2006年第z3期279-283,共5页
Infrared and Laser Engineering
