Fast Recognition Of Moving Road Targets In The Near Distance

In order to solve the shortcomings of traditional road detection equipment,such as wasted labor and large equipment volume.A moving target detection system composed of infrared,microwave and sound wave detection modules was designed.The principle and development process of the three detection methods were introduced.Hardware,software design,and system testing were performed.The main work is as follows:Microwave detection module: The microwave detection module uses a K-LC1 a radar transceiver.This is an FMCW radar and uses a triangular wave as the modulation signal.The local oscillator signal and the reflected signal are mixed.The output contains the beat signal of the detection target information.Triangle wave circuit and beat signal processing circuit are designed.Infrared detection module: Passive pyroelectric infrared sensors have a wide range of monitoring and low power consumption.Infrared circuit was designed.The infrared signal is processed by the circuit and converted into a level signal output.Then it is transmitted to the microcontroller as a warning signal.Voice detection module: The sound wave detection module uses electret microphones as sound sensors.It has high sensitivity and stability.An amplifier circuit,a filter circuit,and a voltage comparison circuit are designed.The acoustic signal is converted by the circuit and amplified.It is divided into pre-warning signal and acoustic signal transmission to MCU.Based on the STM32F103 microcontroller,a software system for detecting signals was designed.The start of the system turns on the infrared and sonic detection modules.After the MCU receives the warning signal,it runs the microwave detection module.The microwave detection module accurately detects the distance of the target.The MCU combines acoustic signal to determine the result,and the result is displayed on the LCD.Using simulation software,the frequency response of the circuit was tested.The required signal is accurately collected.Build a hardware platform.The distance test and recognition rate test were performed on the system.The detection range of the system is more than 15 m and the recognition rate is not less than 90%,which meets the design requirements.