The Design And Application Of Laser Velocimeter System

Laser velocimeter system has been a hot discussed issue in traffic management.As cars has been more and more popular; we need a more efficient method to control or to manage the traffic situation. It takes the advantage of lasert's characteristics of monochromaticity and concentrating of energy, by measuring the frequency to directly measure the speed of the object. Compared with tranditional radar velocimeter, the latest laser velocimeter has great improvement in performance. Moreover, laser velocimeter not only has the advantage of larger effective working area, but also has the capability to use the technology of pointing emission to keep tracking of a certain object in corwded heavy traffic with higher precision.Thus, the main goal of laser velocimeter is to enforce the scrutiny of overspeed vehicle.Especially to reinforce the scrutiny of speeding vehicle on freeway, and to correct and deal with overspeed driving in time, so as to prevent and reduce the incidence of taffic accident.This paper introduces mainly the circuit design of the Laser velocimeter system; include emission module, pulse drive circuit, receiver module, computer interface and controlling software. It is detailedly introduced the function, the operational principle as well as the performance parameters of each portion of the circuit. CPLD technology is employed to integrate digital circuit in CPLD chip, which is of great usage to the miniaturization, stability, noise immunity and on-line modification and upgrade of the system. Followed by filterring the waves and counting in the CPLD module, the signal is transmitted by Serial port to computer for the display and processing.The Laser velocimeter system is designed, debugged and employed to the traffic controlling. And the designed circuit satisfies all parameters of the Laser velocimeter system.