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Atmospheric laser probe pulse laser emission into the atmosphere, through the analysis of the echo signal, the detection of atmospheric composition, aerosol distribution, clouds, temperature, humidity, pressure and wind and other atmospheric characteristics. Lidar by the laser emitting portion, the atmospheric echo signal receiving portion and a data processing part. This paper introduces the atmospheric laser detection electronic simulator which can be used lidar hardware and software debugging. Before the simulator is developed, we in debugging the device of the laser radar system of the photomultiplier tube amplifier, the signal transmission line, a data acquisition card, and a data processing software of the time, First To debug good laser emission light path and receiving light road, using the actual laser received atmospheric echo signals to debug the equipment and software, in the rain, snow and weather conditions, can not get laser atmospheric echo signal, commissioning progress will be affected, and frequently switched lasers will affect the life of the laser. After the the atmospheric laser probe electronic simulator is developed, we use an electronic simulator to generate a laser atmospheric echo signal, so that the debugging of the several devices can be carried out under conditions not dependent on the laser emitting and receiving; but protected from the weather conditions. We can also use the electronic simulator to simulate some difficult to encounter in day-to-day detection kinds of extreme weather conditions, to detect the performance of the system software and hardware. Use the simulator to generate the atmospheric echo signal the aerosol thickness and height, the distance of the detection distance, the intensity of the echo signal can be adjusted. The second part of the paper describes a pulsed laser frequency-locked pulsed laser adjustable peak hold, peak hold solve the locking of the narrow pulse laser. Pulsed laser emission frequency can be adjusted from 10 to 10000Hz, the pulse width of a single pulse frequency of tens of MHz data acquisition card is difficult to adopt such a short pulse peak in about 20 nanoseconds, and the peak of the market to keep the rise time is much larger than the rise time of the laser pulse. Laser pulse repetition frequency in the order of K, using a photodiode (Photodiode), the response time is long, after photoelectric conversion, the voltage amplitude of the slow decline characteristics, can detect the peak value of the pulse laser, but the accuracy is lower, when the pulse the repetition rate of the laser below the K middleweight, and even tens of Hz, must be used to adjust the pulse laser Peak Holding, to extend the pulse width of 20 nanoseconds to milliseconds, accurate data acquisition card taken to The variation of the peak intensity of the laser pulse, thereby locking the lasing frequency. Compared with the peak hold, adjustable pulsed laser peak hold the most important feature is the fast response, the fastest rise time of 4 ns, and adjustable laser repetition frequency between 10-10000Hz The pulse are applicable.
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