It is difficult for radar to implement ballistic missile identification successfully,and it needs to integrate the capabilities of intelligence,self-adaption and cooperation for the identification system.On the basis of traditional identification methods,a multi-feature fusion identification framework based on multi-agent modeling is presented.The reference rule base and internal state base of the agents are established.The process procedure and interactive relationship of agents are given.The simulation based on Swarm platform shows that the multi-feature fusion identification framework can implement fusion identification effectively with correct recognition result.

Considering that the detection probability of false target is high under range-velocity deception jamming,which is similar to angle-measurements to the target,we proposed a low observable target tracking method based on radar network.At first,the angle-measurement set of each radar is partitioned according to the angle information,and the measurements within the same partition are fused.Then the hypothesis testing for the same source measurements of each partition is realized and the missed target measurements are compensated.Simulation results verify the feasibility and validity of the proposed algorithm.

Grey situation commonly exists in target assignment of ship-based UAV formation in coordinated air-to-sea attacking due to limit of early-warning and detection level,incomplete information,and favor and bounded rationality of decision-makers.Aiming at the problem,the target assignment strategy set and payoff matrix of UAV formation and surface ship formation were established.Then,a model of target assignment of ship-based UAV formation for coordinated air-to-sea attacking was constructed based on grey bi-matrix game theory.An improved PSO algorithm was designed to solve the problem with reformed particle location updating formula.Simulations were carried out by using GA,traditional PSO and the improved PSO algorithm respectively.The results indicate that:1) The improved PSO algorithm can avoid local optimum solution and converge to the globally optimum solution;and 2) The grey bi-matrix game theory based target assignment model can well solve the grey problem in target assignment.The results prove the practicability of the model and the effectiveness of the algorithm.

In order to satisfy the demands of stabilized control for airborne platform mounted on multi-rotor Unmanned Aerial Vehicle (UAV),a fuzzy adaptive PID hybrid control strategy with a fuzzy switching condition is put forward,and the control structure has dual rate-speed loops.Analysis is made to the anti-disturbance ability of control structure,and self-adjusting factor and self-learning control rules are introduced to improve the rapid response capability of the system.The variable integral PID control is used to ensure high and stable precision of the system.The fuzzy switching condition guarantees the switching of hybrid control smoothly.Results of dynamic response and steady-state precision experiments show that the adjust time of system is about 20 ms,and the stable accuracy is 0.13 mrad.The proposed method realizes the stable control of airborne platform effectively,and can meet the application requirements of multi-rotor UAV.

The cooperative search with double-plane IRST system is an important passive detection method.Analysis is made to the key problems in double-plane IRST system cooperative search,and the mathematic model for autonomous guiding search is established.Through the target angle information detected by IRST system of the lead aircraft,the angle range of target in the wing aircrafts body axis system is obtained by using detection distance coverage limits of the IRST system.Then,the IRST system of the wing aircraft is guided to search the target area according to the angle range.Two search methods,sequential searching and central searching,are put forward for IRST system of the wing aircraft.The simulation result shows that the autonomous guiding search is effective,and the central searching is more efficient and takes less time.The successful guiding probability is verified by the simulation results of two schemes according to the central searching strategy.The conclusions are helpful for designing double-plane IRST guiding systems.

In the complicated search environment,multi-UAV cooperative search mission may confront with diverse types of targets.Considering the motion features of different types of target,we used a search map method related to probability density function of the targets,and established a reward function appropriate to the coordinated task in order to improve the efficiency of cooperative search.The control architecture combining centralized with distributed control was used,and multi-UAV cooperative search decision making was implemented through predictive control and improved Hungarian algorithm.The decision-making method could improve the search efficiency while avoiding the possible collision of the UAVs.Finally,contradistinctive simulation results demonstrate the validity of the proposed cooperative search strategy.

Aiming at the problem that the noise statistical properties of the visual head positioning system have not been fully mastered,a new method of head attitude tracking based on adaptive filtering is designed,which combines the vision measurement algorithm with adaptive filtering algorithm.On the basis of the n pairs in 2D/3D(image point / space point)matching,the head attitude is calculated out at first by using the Orthogonal Iteration(OI)algorithm,and the head attitude with higher accuracy is then obtained by using adaptive filter.Finally,to the measurement values with time varying noise and the statistics characteristic of the noise is unknown,we made some simulation tests with the head attitude tracking method.The results show that the measurement accuracy of the method is greatly improved,and it is demonstrated that the head attitude tracking method is reasonable and effective.

The damage assessment of aircraft carrier under the attacking of shrapnel is studied. Firstly, according to an analysis of the structure of shipboard aircraft support system and the vulnerability of the main facilities, a model of damage assessment is given by using Fuzzy Analytic Hierarchy Process (FAHP). Then, triangular fuzzy number complementary judgment matrix and reciprocal judgment matrix are used to determine the weights of the main facilities, sub-facilities and the comprehensive damage value, based on which the damage degree of the system is evaluated. Finally, according to the attack effect of a certain type of shrapnel, a damage assessment example is calculated out. The result shows the validity of the algorithm, which reflects that the carrier damage assessment is dependent on the changes of the system's operational effectiveness.

In complex network attacks,the lack of a reliable evidence for decision-makers in attack planning makes it difficult to achieve mission objectives in action.A scientific method for evaluating the complex network node attacking effect is presented.By analyzing the income,loss,and risks of the attacker,we established the corresponding index systems.TOPSIS method was used for making comprehensive assessment and sorting to the attacking effect of the nodes in the network.It can overcome the one-sidedness shortcoming of the traditional node selection method,i.e.,relying on a single indicator of network topology.The study supplies a scientific basis for scheme making in network attacking.

Mixed pixel in hyperspectral image is actually nonlinear mixing of endmembers,which is caused by multiple reflectances and scattering.The traditional endmember extraction algorithms based on linear spectral mixture model perform poorly in finding the correct endmembers.Considering the physical characters of hyperspectral imagery,a new method is proposed to introduce image Euclidean distance into Laplacian Eigenmaps for nonlinear dimension reduction.The proposed method can discard efficiently the redundant information from both the spectral and spatial dimensions．Endmembers are extracted by looking for the largest simplex volume from low-dimensional space.Experimental results demonstrate that the proposed method outperforms the PCA and Laplacian Eigenmaps algorithm.

There are two commonly used methods for dividing the fighter generations,four-generation-fighter method and new five-generation-fighter method.We studied the relationship of a fighter with its onboard fire control system by using four-generation-fighter method and new five-generation-fighter method,and proposed some positivistic ideas of relation between fighter generations and airborne fire control systems.

When the space-based platform shoots the star-image pictures,the background and the camera have relative motion simultaneously.Thus the small moving targets can not be detected through the simple frame difference.Based on analysis to star image model,an image registration method is proposed by extracting feature points to match the same triangle.In the method,optimum threshold is selected for single frame image segmentation and background noise removal.Then,the bright stars are divided by the area,and the feature triangles are made up by the stars that meet the conditions.The motion parameters can thus be obtained in adjacent frames by matching the feature triangle.For reducing the complexity,the star centroid coordinate matrix is processed instead of the whole star image to image registration.Finally,the target track is obtained through a multi-frame track association.Simulation and tests demonstrate that the method can achieve high detection rates and low false alarm rate in the sequence frames.

Evolvable Hardware (EHW) technology has self-organizing,self-adaptive,and self-repairing performance in circuit evolution,and has very important engineering application value.The core of carrying out EHW is Evolutionary Algorithm (EA).When the evolved target circuit is medium-sized circuit or large-scale circuit,the evolution is time-consuming.To solve the problem,a novel accelerated circuit evolution strategy was proposed,which was based on truth table separate technique.Different from the normal algorithm improvement,the new strategy made improvements to the circuit evolutionay algorithm from several aspects.Simulation analysis of typical circuit proved the effectiveness of the proposed strategy.

The methods for testing the precision of Beidou dynamic-dynamic positioning are studied,including baseline length constraint test method,dynamic-instantaneous precision test method,GrafNav software comparison method,real-time and post comparison method and etc.Analysis and verification are made to these methods by using practical data collected in experiments.The result shows that the precision test method has high reliability and effectiveness,which can meet the precision demands of dynamic-dynamic positioning.

The aerodynamic moment of airborne electro-optical pod is very important for design of pod structure.If the wind resistance moment is calculated only according to the model of electro-optical pod without considering the influence of carrier aircraft,the error will be large.Taking the influence of the carrier aircraft into consideration,a two-stage based method was proposed for calculating the aerodynamic moment of electro-optical pod.The azimuth aerodynamic moment of a police UAV in a low latitude area was computed out by using the method,and the result conformed to the physical background and practical phenomenon.Therefore,the effectiveness of the algorithm was proved,which supplies a novel idea for calculating the aerodynamic moment effectively and accurately.

The observability analysis method is widely used in performance evaluation of the Kalman filter. Two observability analysis methods, error covariance matrix and Attitude Dilution of Precision (ADOP), are studied in this paper, and the relationship between the them is analyzed for calculating the degree of observability. To the observability of rotating-IMU's multi-position initial alignment, the 33-state error model of the SINS was taken as its study object. Both the two methods are used for research the best rotation sequence, best stated duration and model order reduction in multi-position initial alignment. The simulation of initial alignment observability is carried out, the result of theory research and simulation show the consistency of two methods.

The true position of the shipboard aircraft should be known clearly in real time when landing.To the distance intersection positioning method of laser range finders,analysis is made to the positioning error.There are two error sources,one is the positioning error of laser range finder,and the other is from the distance intersection positioning method.The error of laser ranging is analyzed and the correcting formula is given based on the principle of laser ranging.Based on model of the distance intersection positioning method,the error sources of the method are found out and the deviation is given.Finally the prospect of positioning method is summed up combined with the error analysis.The analysis indicates that:the error is at decimeter level when the aircraft is at 1 km apart from the carrier,which can satisfy the requirement of the accuracy.

Considering the blind signal separation problem of the convolutive mixture communication signals with same carrier frequency and modulation by a single channel,a new algorithm was presented for convolutive blind signal separation.Firstly,a single channel mixing signal model of MISO was transformed into a multi-channel mixing signal model of MIMO,based on the characteristics of oversampling.Then,the influence of the time-delay differences between mixing signal components to the structure and rank of mixing matrix of MIMO was studied.Finally,mathematical derivation proved that:if the time-delay difference between mixing signal components was the integral multiples of symbol velocity,the mixing signal is not blindly separable.And simulation results showed the validation of the algorithm.

In order to study air pressure influence on imaging quality of vehicle-mounted photoelectric system,a mathematical model of air pressure leading to image blurring of photoelectric system was established based on the analysis to the influence of air pressure variation on defocusing of photoelectric system.Optical system model of a certain type of wheeled artillery sight was established,the simulation analysis of system model was carried out by setting different ambient air pressure,and simulated images of the sight under different air pressure were obtained finally.Simulated images were evaluated by using gray mean gradient,and the conclusion was summarized: the lower the air pressure,the more blurred the image,and the worse the imaging quality of the sight.The study is of great reference value to environmental adaptability design of new type vehicle-mounted photoelectric system.

In the laser scanning display technology,the displayed images based on Lissajous graphic have an irregular scan path.In order to correctly display the input common progressive raster image by Lissajous scanning,it needs image conversion.According to a certain method for calculating the pixel coordinates and pixel timing,the relationship of timing and coordinates between the current display pixel and the next pixel can be calculated out.Then,the corresponding coordinate pixel value can be extracted from the input image to complete an image of Lissajous scan display.Simulation was made to images of 880*660@25Hz by using Matlab,and the pixel coordinates and timing data of Lissajous scanning display were obtained.Statistics was made to the distribution of those data.The simulation results show that the algorithm can convert the input image to Lissajous scanning effectively.

Considering the problem that the parallax of an optical sight with small field-of-view can't be tested with traditional method using collimator tube, we established a parallax testing system by using specialized clamp, two-axis displacement platform, a photoelectric theodolite and optical platform. The photoelectric theodolite is taken as the measurement basis. The maximum parallax is tested when the theodolite is on the extreme position of exit pupil in azimuth/pitching direction. Experimental result showed that the system is stable, and the method is easy in operation and has high measurement accuracy.

Aperture coupling was simulated under electromagnetic radiation environment for a helicopter with tangential vector finite element software HFSS.In software HFSS,the size and quantity of the openings needed for external retrofit to the helicopter was simulated,and an emission source interference was used outside the aircraft.Thus it could reflect the impact of electromagnetic radiation to the airborne electronic equipment.Simulation was made to aperture coupling,and the result was compared with the DO-160F standard.The relationship of the radiation energy with frequency and phase,and the radiation energy at different locations,were also studied.Conclusion was obtained through numerical analysis and simulation results,which can be used as a theoretical basis for making openings in helicopter in retrofit.