High-precision infrared pulse laser ranging for active vehicle anti-collision application

In this work, a high-precision infrared pulse laser ranging system based on FPGA and microcontroller Atmel16 is proposed for active vehicle anti-collision application, and the key technologies of this system including optical device, laser receiver component, and time-of-flight stretching component are studied deeply based on the principle of the pulse laser time-of-flight measurement. The light energy transmission is analyzed in detail to choose the proper transmitted and receiver laser diode. Specially, the method of the time stretching based on the charge and discharge of the high-precision capacitor using the constant current sources is adopted to realize the measurement of time-of flight. The practical running of system prototype and test results show that the precision is +0.1m, the repetition rate is 1 kHz, and the distance measurement range is up to 60 m from 1.5 m. So, this system can accurately detect the distance between the cars, and can efficiently avoid traffic accident, therefore, this system has greatly practical and economic value.