Research On Laser Detection And Positioning Technology Based On Four Quadrants

With the rapid development and application of laser threat technology such as laser weapons,the research of laser warning system also needs to be more in-depth.In order to achieve better alarm protection,the field of view of the alarm system is particularly important,but the alarm in large field of view often needs to face two problems: the detection of saturation amplitude voltage signal and the nonlinearity of edge angle measurement.These two problems are also the key to restrict the detection field of view and measurement accuracy of the four quadrant system.In this paper,a set of four quadrant laser detection and positioning system was built based on the application background of large field of view satellite laser warning,and the principle scheme of large field of view laser warning was studied and the model algorithm was improved.Firstly,the paper described the research background of the subject,made a comparative selection of detection methods and detection devices,and based on the index requirements of the laser warning system,the functional principle and technical points of each component of the laser detection and positioning system were introduced in detail from the aspects of hardware and module composition.Secondly,aiming at the problem of how to improve the dynamic range of the system,a control scheme combining light intensity adjustment and gain control was proposed to improve the dynamic range,and an improved motor control scheme adapting to any incident polarization direction was developed,finally the specific design of the module and the hardware implementation of FPGA were described.Then,aiming at the problem of how to realize the signal detection in large field of view,this paper innovatively proposed an energy inversion model based on waveform integration method to detect the saturation amplitude voltage signal.By calculating the waveform integral value in the nonlinear region,an energy inversion model based on the waveform integral method was established,which solved the problem that the traditional peak extraction method couldn't detect the saturation amplitude voltage signal.The simulation and experimental results showed that the model could expand the detection range of the system energy to 10.25 times of the peak extraction method,and could be used to detect the saturation amplitude in large field of view to broaden the detection field of view.Finally,aiming at the problem of how to improve the angle measurement accuracy of the system in large field of view,an improved positioning algorithm and error correction model were proposed to improve the positioning accuracy and reduce the measurement error.Through analyzing the key links that affect the measurement accuracy in the process of positioning and measuring angle,the paper made the selection of spot model,the improvement based on the algorithm of addition and subtraction,and the establishment and modification of error model,the improved algorithm reduced the nonlinear effect of edge angle measurement in large field of view,the experiment showed that the wave integral method and the improved algorithm could broaden the field of view of 4-qd system to ± 40 ° and had an angle measurement accuracy of 1 °.