Research On Target Measurement System Based On Shock Wave

The shock wave-based target measurement system is a technology that uses an acoustic localization algorithm and a hardware processing system to collect and process acoustic signals to determine the target position of a sound source.Whether in the military field or in the civilian field has a wide range of application prospects.In the military field,such as artillery reconnaissance and target measurement,this technology has the advantages of passive acoustic positioning and good concealment^[15].Civil use has also been widely used,such as mobile phone and robot tracking system.This thesis mainly studies and analyzes the layout of sensors,and designs the hardware architecture and unit circuits of the system.The shock wave-based sound source localization technology can calculate the time difference between the arrival of the shock signal to each sensor and design the algorithm to solve the target position.This thesis introduces the principles of basic cross-correlation method and generalized cross-correlation method,analyzes the advantages and limitations of the basic cross-correlation method,and the advantages and applicability of the generalized cross-correlation method.The experimental analysis of the error of the estimated time delay between the basic cross-correlation method and the generalized cross-correlation method is given.Several commonly used generalized cross-correlation method weighting functions are listed.By comparing with the basic cross-correlation method,several weighting functions are analyzed.Strengths,weaknesses and limitations.This thesis researches and analyzes the influence of sensor array on the measurement accuracy.On the array,the single-plane array model is a six-element planar array and the double-plane array model is a four-element square array.The principle and the formula derivation of these two types of array formations were performed respectively,and some parameters affecting the measurement accuracy were analyzed experimentally.The effect of the change of the target distance and the distance between the sensors on the measurement accuracy was experimentally analyzed for the six-element plane array.The effects of various parameters on the measurement accuracy of the biplane quadruple square array were experimentally analyzed,including the distance between the sensor elements,the distance between the sensor arrays,and the lateral and longitudinal distance changes between the sensor array and the target surface.Impact on measurement accuracy.In the formation design,other related arrays have also been designed,and the simulation results are listed for comparative analysis.In this thesis,the hardware architecture and unit circuit of the aircraft gun target measurement system are designed.The overall design of the mainstream“FPGA+DSP+ARM”data transfer bus converter is given.The circuit design of each unit of the hardware architecture is specifically introduced,such as the power supply.The unit circuit design of module,clock circuit module and reset circuit,and also detailed the interface circuit design of ARM and DSP and FPGA.The design of the first to achieve the front end of the signal acquisition,select the AD9226 chip to achieve analog-digital conversion,select the EP4CE30F23C8 type FPGA to achieve clock management,data cache,data storage and transmission functions,due to the advantages of DSP computing power,select the TMS320C6657 signal algorithm Processing function,select STM32F767IGT6 type ARM chip for control,select CC1000 chip for data wireless transceiver function.