Target Detection Technology Of Navigation Radar

Marine navigation radar can provide the information of azimuth and range dimension of target intuitively,and it is convenient for ships to avoid obstacles.It plays an important role in the marine electronic system.Because the physical size of the ship is larger than the radar resolution unit,the point target detection and tracking method is no longer applicable;the navigation radar working environment is complex,and the sea clutter using the traditional detection and tracking system will cause a large number of false alarms and missed detection in the detection process.In this paper,the extended target detection technology is studied on the background of navigation radar system.An extended target detection method based on tracking feedback is proposed.The method couples the detection and tracking process,feeds back the predicted target position and the innovation autocorrelation matrix obtained by Kalman filter to the Bayesian detector,obtains the prior probability expression of the Bayesian detector,and realizes the adaptive adjustment of the threshold in the detection plane.The specific research contents of this paper are as follows:1.The simulation technology of sea clutter echo for X-band navigation radar is studied,and the echo image of navigation radar is simulated to provide a platform for the follow-up simulation.The influence of platform motion on echo is also analyzed.The statistical model of sea clutter amplitude characteristics is built by using the measured data,and the distribution characteristics of sea clutter in each region are quantitatively tested by KS test method,which paves the way for the design of subsequent detectors and the simulation of detection performance.2.The optimal CFAR detector detection threshold calculation method and the classical CFAR detector architecture under different clutter distributions are studied.The performance of CFAR detectors of mean class,ranking class and intelligent index class in uniform region,clutter edge region and multi-target scenario is compared with simulation and measured data.Complete single frame target CFAR detection.3.Aiming at the low accuracy of CFAR detection for single target in low SNR,an extended target detection method based on tracking feedback is proposed.The target is modeled as an elliptic model,coupled with Bayesian detector and Kalman tracker,and the performance of target detection and tracking is optimized jointly.By using the simulation data,the method is compared with the classical detection and tracking method,and the results prove the superiority of the proposed method.The validity of the proposed method is proved by the measured data.