Research On Detection And Recognition Of Low Altitude Small Targets

In the field of military application,enemy low-altitude small aircraft carries out ground target detection,electromagnetic signal detection,electromagnetic interference and other activities,which easily poses a threat to the ground weapon system and personnel,and becomes a new threat to the ground battlefield.In the civil field,with the improvement of the national economy and the opening of the corresponding low altitude policy,the application of low-altitude aircraft with convenient operation,full performance and functions is more and more extensive.However,due to the negative impact of the use of unmanned aerial vehicles,new requirements are put forward for the management and control of unmanned aerial vehicles.For low-altitude defense applications,this thesis reports work on detection and recognition of low altitude small targets.The main contents can be divided into four parts: the technical scheme of photoelectric imaging detection system,the detection technology of small low-altitude targets,the identification and detection technology of rotatory unmanned aerial vehicle,the cross-platform migration of target recognition algorithm based on Android platform.The main research contents are as follows:1)Target detection technology based on motion features is studied.A dynamic target detection algorithm based on the combination of three frame difference method and vibe algorithm is presented according to characteristics analysis of target motion information.Analysis of detection speed and test results shows the algorithm has a good comprehensive performance.2)Target recognition technology based on local appearance features is studied.A classifier for identifying the rotor UAV is designed with direction gradient histogram and support vector machine algorithm after the feature extraction algorithm being analyzed and the characteristics of the target(small rotor UAV)being test.The experimental results show that the recognition accuracy of the classifier is good,and it can realize the recognition and detection of the target UAV.3)A embedded technology scheme based on Android platform is studied.An Android hardware as development platform is selected.Firstly,the configuration of Android and Open Cv development environment are finished.Secondly,the application components needed in the process of Android application development are analyzed.Finally,the transplant of the third-party local algorithm library is finished,and the basic framework APP is designed based on Android application components,controls and Android NDK.The detection and recognition system is developed in the paper to realize the location extraction of low altitude dynamic small target in the field of view and the recognition anddetection of rotor UAV.At the same time,the embedded system based on Android have the advantages of redevelopment and enrichment,which has important application value in the application of vision based low altitude monitoring and management engineering.