Study On Traffic Data Collection System Of Urban Road

In order to collect traffic information, this paper designed a traffic information collection system based on a single induction loop and multilane. The system can accurately collect the changes of frequency when vehicles go through the induction coils, and precisely get the traffic flow. At the meantime, this paper confirms the vehicle run spot by distinguishing frequency wave inflection point while vehicle running in loop, then calculates the vehicle average speed.First, this paper describes theory model of induction loop collection technology, then test and verify the theory's correctness and feasibility by application. It spends a transitory time for vehicles go across single induction loop, while the system should response accurately and fast.The processing unit of this collecting system was established by the use of AT91SAM7X256 microprocessor with ARM7 kernel and STM32F103CB microprocessor with ARM CORTEX M3 kernel, that have large storage space and high-powered process ability. STM32F103CB microprocessor is mainly responsible for the collection of oscillation frequency and time. AT91SAM7X256 microprocessor's main job is to deal with the original data and get the traffic information of vehicle flux and speed. Then, the design of hardware and software of this system was given.Lastly, its availability is done by practical experiment. The results prove that the system not only greatly increases the accuracy and reliability of detection, but also provides a reliable foundation for applying to next practice.