In the Satellite-Laser-Ranging(SLR) system the widely used Geiger-mode Avalanche Photon Diode(G-APD) is affected by the limit of dead time, which leads to only one single trigger chance in one detector duty cycle. Once triggered by noise first, detector can no longer response to echo photons during the same cycle. In order to solve the problem, a solution is given in the thesis by using sensor arrays, which enables separate working of each APD and improve the photon detect efficiency hence. In the thesis the Multi-pixel Photon Counter(MPPC) is used as echo photon detector, its application in the Laser-Ranging system is studied, and is verified per related experiments. The thesis focuses mainly on:（1） A temperature control system is developed for constant temperature refrigeration of the detector with accuracy of0.2℃. The system is applied into the 4*4 MPPC array. In the environment of 22.5℃ and 10℃the detector input source is red light and the counter status is monitored by oscilloscopes. The result shows that in a low-temperature situation the noise is lower than in normal-temperature cases. The max pulse amplitude is 26 mV with rising-edge of512ns in 10℃ case, and is 18 mV with rising-edge of 777 ns in case of 22.5℃.（2）4*4 MPPC array packed with temperature control system is applied as echo photon detector. Experiments targeting ground Diffuse-Reflection-SLR target and Ranging Satellite AJISAI are taken place based on the "Single Emit & Single Receive" separation Ranging System of Yunnan Observatories. In ground target experiments main wave and echo time are acquired by event timer. The RMS of ranging is 21.7 cm according to data processing, which accords with the laser pulse width and the error resulting from shape effect of diffuse reflection targets. In experiments targeting AJISAI oscilloscopes are used for sampling as a result of performance limitation of detectors and lower echo probing probability.（3） Gate control methodologies and techniques of MPPC array are studied. Gate control circuit system includes light-pulse source, gate-controllable adjustable high DC voltage source, pre-amplifiers. Data sampling and analysis are perform by the system in case of with/without gate-control unit. In case of without gate-control unit the pulse signal amplitude is 0.9 V with recovery time of 20 μs, while in gate-control mode the amplitude is 1.8 V with recovery time of round 4 μs. Theoretical and experimental basis is built for multi-channel MPPC array gate-control circuit.As conclusions the thesis demonstrates, compared to sensor unit the sensor array has certain advantage in detection, which has higher efficiency in photon detection. Lower temperature working condition effectively improves capability of detectors. Using gate-control mode can effectively lower the jamming of noise. Ground target and satellite laser ranging experiments show that the improved MPPC array have the probability to be applied in laser ranging system.
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