Research And Realization Of Signal Processing Algorithm For Missile-borne Monopulse Radar

As an advanced guided weapon for attacking ships at sea,anti-ship missiles have the characteristics of long range,great power,and high hit rate.They play an important role in long-range precision strikes,intelligent detection,and target tracking.When missile-borne radar detects and tracks targets on the sea surface,The existence of sea clutter severely limits the ability of radar to detect targets.In order to improve the detection and identification capabilities of anti-ship missiles in complex scenarios,the modeling and characteristic analysis of sea clutter has become the main focus of anti-ship missile research.At the same time,in the short-range phase,large targets such as ships can be regarded as extended targets.As the distance between the projectile and the target is getting closer,the angle measurement error caused by the angular flicker increases,which limits the accuracy of anti-ship guidance.Therefore,studying the problem of suppressing angle flicker and improving the accuracy of radar angle measurement is of great significance to the development of precision guidance.In summary,this article takes the detection and tracking of large-scale ship targets on the sea surface by anti-ship missiles as the application background to carry out the signal processing research of anti-ship active radar homing guidance technology.The sea clutter faced by the missile-borne radar sea surface detection was modeled and analyzed,and the angle glint suppression method faced in the short-range tracking stage was studied,and a single pulse angle measurement method based on range Doppler image was proposed.At the same time,for the problem that the angle glint is aggravated by the three-dimensional rotation of the ship target under high sea conditions,an angle measurement method based on the rearranged time-frequency image is proposed,which improves the signal-to-clutter ratio and reduces the angle measurement error.It has a significant suppression effect,and the single pulse tracking algorithm is designed and implemented based on the embedded GPU.The specific content is as follows:Firstly,the dynamic sea surface echo is modeled and analyzed.The sea spectrum model is used to generate the physical sea surface,the sea surface is divided into panels,and the backscatter coefficient of each panel is calculated based on the Kirchhoff method and the perturbation method of the two-scale model,and the sea clutter echo is generated.Through the analysis of different parameters,the amplitude distribution characteristics and power spectrum characteristics of sea clutter under different sea conditions,the correctness of the simulation data is verified by the IPIX measured data,and it is used for the next single pulse angle measurement method of the complex sea surface background.To pave the way.Secondly,the problem of angle glint in short-range sea exploration is studied,and a single pulse angle measurement method based on range Doppler image is proposed.A ship target model was established and introduced the distance Doppler principle,motion compensation method,two-level constant false alarm detection method,and angle measurement principle.Through simulation experiments,it is concluded that this method can effectively suppress the angle glint problem moving targets under steady-state sea conditions.Regarding the problem that the non-stationary state of the target in high sea conditions exacerbates the angle glint,an angle measurement method based on the rearrangement of time-frequency images is proposed,the advantages and disadvantages of different joint time-frequency methods are studied,the flow of the rearrangement method is given,and the use of this method is explained through experiments.The method performs instantaneous imaging angle measurement,which can effectively reduce the angle measurement error.Finally,the single pulse tracking algorithm is implemented based on the embedded GPU.The internal architecture of Jetson TX2 chip based on NVIDIA is introduced,the embedded programming model and linear hierarchical structure based on CUDA are briefly described,the parallel implementation method is analyzed and the performance analysis is given,which meets the accuracy and real-time performance of the algorithm implementation.