Research On Complex Radar Signal Sorting Technology

At present,the electromagnetic environment is becoming more and more complex.The reconnaissance receiver receives the complex radar signals from all directions in a short time.These signals overlap each other and their modulation parameters are very complicated.To study and analyze the radiation sources in the electromagnetic environment,we need to sort out these interlaced pulses firstly.The results of signal sorting directly affect the subsequent analysis results.Therefore,radar signal sorting technology under complex electromagnetic environment is a very important subject.Nowadays,more research results have been made on the sorting technology based on traditional five parameters,among which the clustering sorting algorithm and PRI sorting algorithm are hotspots.Because of the bottleneck of traditional parameters,it is also an important research direction to use the intra-pulse characteristics for sorting.In addition,it is of great research value to process the existing algorithm to form a complete sorting model.Therefore,a comprehensive and in-depth study in the above aspects are studied.And four innovation points are proposed in this thesis.The main contents are as follows:Firstly,the characteristics of the sorting parameters are analyzed and the flow of the typical sorting system is combed.Aiming at the disadvantages of too many sorting series and not suitable for complex signal sorting in traditional processes,an improved sorting model is proposed.The main flow of the new sorting system is as follows:(a)Matching the known radar template and deducting the known radar signals.(b)Dividing the remaining unknown radar signals by using DOA parameters for reducing the density.(c)Co-clustering based on the inter pulse characteristic parameters and the intra pulse characteristics parameters,and dynamically modifying the clustering parameters according to the clustering results.(d)Sorting the signals by PRI to get the final results.Then,the pulse modulation mode of typical signal is combed,and the complexity features and resemblance coefficients are extracted.According to simulation analysis,the distinction and the stability of resemblance coefficients' Cr2 is best.Then the characteristic of traditional clustering algorithm are studied.The k-means and SVC algorithms are simulated and analyzed based on Cr2 feature.On this basis,the method of using Cr2,PW and RF for clustering sorting is put forward.The superiority of the joint clustering thought is proved by the simulation which is based on SVC clustering method.Finally,The statistical histogram method,CDIF method,SDIF method,PRI transform method,improved PRI transform method,plane transform technology and a sorting method for sliding PRI are analyzed and compared.The applicable conditions of these algorithms are analyzed.Two new algorithms are proposed for PRI sorting algorithm.(a)A PRI sorting algorithm based on dynamic two-dimensional eigenvector matching is proposed.The simulation analysis shows that the method is suitable for the complex PRI and it is less affected by the measurement error,and the sorting result is good when there are missing pulse and false pulse.(b)Based on the characteristics that the dynamic two-dimensional eigenvectors matching sorting method and improved PRI transform method is diffirent,raising strengths and avoiding weaknesses,a new comprehensive sorting method is proposed.The correct sorting ratio of the comprehensive sorting method is high.The method has a better sorting result and can be used for sorting complex signals with more modulation types.