高光谱碘分子和双边缘多普勒测风激光雷达技术比较

Comparison Between High Spectral Iodine Filter andDouble-Edge Doppler Wind Lidar Techniques

对采用原子滤波器的激光雷达技术和双边缘技术的灵敏度和误差进行了详细的讨论。对于纯 Rayleigh散射 ,双边缘系统的灵敏度高于基于碘分子的激光雷达系统 ,而对于 Rayeigh- Mie混合信号 ,双边缘系统通过采用特殊工作点的办法 ,有效解决 2种信号响应不同的问题 ;但同时该工作点的选取使得系统灵敏度降低 ,误差增加。对于后向散射比不是很大 (<10 )的情况下 ,误差可以控制在1m/s以内 ,完全可以满足测量要求 ,因此对于对流层顶部和平流层测风很适合。基于碘分子的激光雷达系统利用碘分子的高吸收性对 Rayleigh- Mie信号有效的进行分离 ,并且灵敏度随着后向散射比的增加而增加 ,从而对底层大气的探测特别有利。

This paper discusses parameters of double edge systems especially double edge systems working at a special point and lidar based on I 2 filter. For Rayleigh signals, double edge systems have a higher sensitivity. For Rayleigh-Mie mixture signals, a double edge system removes the effect of Mie signals by selecting a special working point and at this point Rayleigh and Mie signals have the same responsibility. However, the selection of this working point decreases the sensitivity and increases the measurement error. When the backscattering ratio is less than 10, the measurement error is smaller than 1m/s. Hence, it is fit for top troposphere and stratosphere wind measurements. Lidar based on iodine filter can separate Rayleigh and Mie signals by using the high absorption character of iodine, and its sensitivity increases with increasing backscattering ratio. It is powerful in low atmosphere wind measurements.