介绍了光强闪烁激光雷达回波信号中背景噪声的分类,通过某次实验中实验条件的变化, 获得了采集卡本底噪声、 放大器本底噪声、PMT本底噪声、自然背景光噪声和散粒噪声等不同背景噪声叠加在一起的大小和方差信息, 以及不同噪声各自本身的方差信息。通过不同噪声之间的比较,发现在未接收激光大气散射回波信号时, 放大器本底噪声占主导,自然背景光噪声相对于其他噪声是小量;在接收散射回波信号时,近距离 内(低层通道2 km, 高层通道4 km)散粒噪声占主导,远距离上处于弱势。实验结果确定了不同噪声对总 背景噪声的贡献程度,为光强闪烁激光雷达从散射回波信号中提取大气湍流信息提供了依据,也为消除 噪声对有效信号的影响提供了指导。

The classification of noise in the returned signal of residual turbulent scintillation(RTS) lidar was introduced. Based on changing condition of experimental status, the amplitude and variance of different sum of the baseline of A/D card, amplifier, PMT, background noise and shot noise were acquired. By comparison of different noise, it is found that the baseline of amplifier is primary and background noise is small when telescope doesn’t receive atmospheric scattering signal. When telescope receives scattering signal, the shot noise is primary in near range (2 km for near channel and 4 km for far channel), and is small in far range. The experiment results show different impact of different noise on total noise, and so are instructive on acquiring atmospheric turbulence form returned signal of RTS lidar, as well as reducing influence of noise on effective signal.