Ensuring the stability of Satellite Laser Ranging data is crucial to fully capitalize on ground-based SLR technology's benefits. Additionally, it enables scientists to meet the stringent millimeter-level stability prerequisites required for scientific applications and perform subsequent ranging tasks. This study delves into the factors that influence the stability of the SLR system at the Yunnan Observatories. The analysis primarily focuses on the measurement errors associated with system delay and draws on domestic and international research on laser ranging systems' data stability. For the measurement errors of system delay, the stability of the 53 cm SLR system at the Yunnan Observatories was improved. To address the issues of timing conflicts between ground target measurements and satellite ranging, as well as the ground target calibration errors caused by meteorological parameter changes over long time intervals, the lack of a real-time monitoring system for laser power, and time-walk errors due to inconsistencies in the echo rate between ground target calibration and satellite laser ranging a modified system was designed and developed to improve the system stabilities. The main work and research achievements are as follows:A comprehensive investigation was undertaken to scrutinize the factors responsible for the stability of the SLR system. Based on the findings, a thorough evaluation was conducted to assess the strength of the 53 cm SLR system at the Yunnan Observatories.Secondly, the multivariate function fitting method established a correlation of the ground target calibration data that varies with meteorological parameters. Aiming at the problem of timing conflict between ground target measurement and satellite ranging in the system delay measurement and lack of real-time in the long time interval, the real-time ground target delay data were obtained through the established change relationship. Using the sp3 precision orbit to make difference with the measured data and correction data respectively, the mean value of the difference is 2.335 cm and 2.331 cm, and the RMS value of the difference is 2.07 cm and 2.01 cm, with a difference of 0.004 cm and 0.06 cm, which shows that the correction method of this thesis is effective and can be applied in the real measurement work.Thirdly, a creative design and implementation of a real-time laser power monitoring system was achieved. This system indirectly measures the laser emission power using transmitted light without altering the original optical path, thus avoiding any impact on the optical path and energy attenuation. In the monitoring experiments, the maximum deviation between the monitored power and actual power was 3.75% of the current value, and the residual standard deviation σ was 0.0165. This system meets the stability and accuracy requirements for SLR and has the potential for extended applications, providing support for subsequent data processing, system troubleshooting, and experimentation.Lastly, a feedback control system for the echo rate was designed to respond to the time-walk error caused by the variation in laser echo energy. This system added a Glan prism to the existing ranging optical path and employed a PID control algorithm to regulate the echo rate, aiming to achieve single-photon detection. Doing so allows for more precise control over the detection process, which is crucial for maintaining the accuracy and reliability of the SLR data.
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