The Design Of Target Detection System At Close Range

By sensor detection technology,a short-range target rapid detection and identification system is designed in this paper.In order to realize the fast and accurate identification of different targets,the characteristics of different types of targets are systematically analyzed.A variety of sensors are used in the design to specifically identify targets.For sensor applications,the main work of this paper is as follows:Magnetic detection module: used for detecting and recognizing ferromagnetic targets,selected HMC1001 single-axis magnetic sensor,designed a signal amplification circuit,second-order RC filter circuit and secondary signal amplification circuit,in which the primary signal amplification circuit uses AD623 instrument Amplifier,101 times the amplification,secondary signal amplifier circuit using OPA228 differential amplifier to eliminate the magnetic field interference.Infrared detection module: for sensing and recognizing human infrared signal,using RE203 B dual-element infrared sensor,designing the infrared signal conditioning circuit using the IC chip SP012,converting the infrared analog signal to digital through the SP012 built-in operational amplifier circuit and voltage comparison circuit signal.Radar Ranging Module: It is used to implement the early warning and distance measurement functions of moving targets.The CFK024 radar custom module is selected to control the AD9833 to generate triangular wave modulated signals through a single chip microcomputer.A second order Butterworth bandpass filter based on the LM324 is designed and implemented.Distance ranging function for close targets.Acoustic signal module: used to realize the sound warning function,select the omnidirectional electret acoustic sensor,use the audio power amplifier LM386 to set up a signal amplifier circuit,this circuit can amplify the audio signal 200 times,through the adjustment of the 5 pin The resistance of the resistor allows the signal strength to be adjusted.The thesis introduces the working principle of the rapid recognition of the selected detection technology,and designs the system hardware circuit and related signal processing software algorithms.In the test section,functional tests are performed on each detection module of the system and the effective distance of each detection module is determined.The test results show that the effective detection distance of the magnetic detection module is 2 meters,the effective detection distance of the infrared detection module is 3.5 meters,the effective warning distance of the acoustic signal detection module can reach 10 meters,and the radar module can measure distance within 5-15 meters.The error is minimal.Finally,in the overall system performance test,each detection module can work normally and the work performance meets the design requirements.