Characteristics Analysis Of Signal-Induced Noise Of Photomultiplier

As an emerging active modern optical remote sensing device,Lidar has the advantages of high detection sensitivity,high time,spatial resolution,large detection range,all-weather time and the ability to detect the height range that other detection equipment cannot observe,and become a powerful means of detecting the middle and upper atmosphere.Under the new technical conditions,in order to obtain higher-resolution,high spatial resolution mid-to-high-level atmospheric profiles and their refined structures,we use more powerful lasers and larger optical telescopes for atmospheric detection.At the same time,in order to receive the weak echo signals of the middle and upper atmosphere,especially the metal layer and ensure high signal-to-noise ratio,the photomultiplier tube with high quantum efficiency and high sensitivity photon counting mode is usually used in the laser radar system,and the result is the acquisition.The nonlinear distortion caused by the signal induced noise caused by the near-field strong echo signal in the echo signal is more obvious.In order to obtain accurate and reliable atmospheric parameter data,it is necessary to solve the problem of nonlinear distortion of the signal caused by the photomultiplier signal induced noise.At present,the signal processing methods for signal induced noise and nonlinear distortion caused by it mainly include mechanical chopping,electronically gated PMT,SIN model and external electric field,all of which have their inadequacies.Especially for the analysis of the characteristics of SIN,the selection of the light source greatly interferes with the accuracy of the experimental results.For this reason,this paper proposes a method of fast chopping and designs the generating device.On this basis,it is proposed twice.Method and device for chopping;A new detection system for signal-induced noise of photomultiplier tube was designed with these two devices.The characteristic of signal induced noise with respect to incident pulse width and light intensity was analyzed.A fine model of signal induced noise was established.In this paper,it is proposed that pulsed light with a large pulse width can beregarded as a new view that two small pulse widths are continuously emitted,and a new signal composed of two pulse widths is compared with a large pulse width signal.The correlation coefficient of induced noise is as high as 0.98.A new idea is provided for deducting signal induced noise from radar data.