利用TDC-GP21的高精度激光脉冲飞行时间测量技术

High-precision measurement technology of laser pulse flight time based on TDC-GP21

采用微小时间间距测量芯片TDC-GP21设计实现了高精度激光脉冲测距系统。详细论述了TDC-GP21的工作流程与外围电路,研究了光信号接收与放大电路,并对跨阻放大器理论进行了详细的理论论述与分析。同时,讨论了三角波定比延时脉冲时刻鉴别法,降低了系统对激光器回波信号幅度变化的要求。经实验测试获得了厘米量级的激光脉冲测距系统。系统结构简单,可实现程度高,精度高,功耗低,体积小,可以满足高精度距离测量需求。

With advanced minute time interval measurement chip TDC-GP21 which is an applicationspecific integrated circuit （ASIC）, a high precision pulse laser ranging finder system was designed andachieved in this paper. Meanwhile, the workflow chart and external circuits were discussed. Opticalsignal receiving and amplifying circuit were also studied the basic theory of transimpendance amplifierwas also discussed and analyzed in detail. Further more, the method of triangle wave fixed propagationdelay was put forward for time distinction which could greatly reduce the requirements of echo signalamplitude. That was pretty important to laser ranger finder. The results of the experiment prove that acentimeter accuracy system can be achieved with the above technology. At last, the pulse laser rangingsystem with small size which is easy to acquire has really simple structure and can achieve high degreeaccuracy which meets high precision laser distance measurement requirement with low powerconsumption and cost.