Based on our perception of the features of patrol searchthe viewpoint is proposed that when the antisubmarine patrol aircraft uses sonobuoys for searching submarinesthe deploying of linear arraythe monitoring of linear array and their relationship should be taken into integrated consideration.The definitions of single array and complex array are givenand the analytical models of the search situation of the single/complex linear array and the optimal configuration of the complex linear array are established.The essence of the patrol search methods of anti-submarine patrol aircrafts and the basic problems to be solved are analyzed.Two typestotally six kinds of aircraft patrol methods using sonobuoys for submarine search are proposed. Based on the analysis of the search situation and the search methodstwelve comprehensive conclusions are drawnwhich provides a theoretical and technical basis for anti-submarine patrol aircrafts in the patrol search using sonobuoys.

The characteristics of the ocean background and the ship target in high-resolution SAR images were analyzed. A two-stage fast detection algorithm for ship target detection in high-resolution SAR images was proposed. At the first stage, an improved spectral residual visual salience calculation model was used to quickly obtain the visual region of interest. At the second stage of the detection, we designed a local maximum posteriori probability classifier for pixel classification based on Bayesian theory in binary hypothesis testing. After the parameter estimation, the criterion was completed and the pixels in the significant region were divided into two categories to achieve the target detection. Experiments were carried out using Terra-SAR-X and a large amount of military satellite data. The results showed that the proposed algorithm has good detection performance and is more in line with the application requirements of the actual high-resolution image ship target detection. By comparison with the conventional detection algorithm, it showed that: the algorithm proposed in this paper can not only reduce the false alarm caused by speckle noise, but also improve the detection speed by 25 percent to even 50 percent.

To deal with the model uncertainties and unknown external disturbances in the process of attitude control of quad-rotor aircraftsa novel Non-singular Fast Terminal Sliding Mode Control (NFTSMC) method based on Finite-Time Disturbance Observer (FTDO) is proposed.FirstlyFTDO is designed to observe the model uncertainties and unknown external disturbances in real timeand a novel NFTSMC controller is designed based on observed values.The proposed control law can not only depress the model uncertainties and unknown external disturbancesbut also improve the tracking speed and control accuracy of the system.The stability of the control system is proved through Lyapunov theory.Finallythe simulation results demonstrate the effectiveness of the proposed control method.

Aiming at the shortcoming of the singular optimization objective in the general research of the Wireless Sensor Network (WSN) multi-target cooperative tracking, a new multi-target coupling cooperative task allocation method based on Q learning is proposed. A cluster merging method is used to solve the competition conflict problem in task allocation in the case of multi-target coupling. Firstly, Q learning method is used to select the optimal time for merging clusters at the stage of multi-target encountering. At the same time, the suitable Q learning function and return function are found out, and the most suitable switching scheme of the cluster head for the stage of target parallel moving is obtained. Then, under the premise of ensuring sufficient remaining energy, the schemes to select the optimal cluster heads and cluster members of different stages are given by using the information utility function and the number of the smallest cluster members. Finally, the target information is separated according to the target tag. The simulation results show that the algorithm can optimize the multi-target coupling, which can satisfy the demand for tracking precision, and has the advantage of reducing the system energy consumption and prolonging the life cycle of the network.

As a main countermeasure mode for the UAV remote control link, the full time, broadband, suppressive electromagnetic jamming may waste jamming energy and have impact on the environment. Follower jamming and the turn-on strategy generated based on its jamming range can solve the problem effectively. In this paper, the follower jamming hyperbolic and the limited power jamming range inequation are conducted based on the time domain and power conditions of the follower jamming to the UAV remote control link. Accordingly, the effective jamming ranges under different parameters are confirmed and a reasonable jamming turn-on strategy is put forward. The simulation results show that the strategy can meet the changes of the parameters well, which is of great significance for improving the effectiveness of electromagnetic jamming.

The goodness-of-fit test is often used to select the clutter distribution model, but it cannot solve the problems of overfitting and the multi-model optimization. In this paper, a new method based on Bayesian Information Criterion (BIC) is proposed for clutter model selection, and the Reverberation Chamber (RC) is taken as the simulator of the radar clutter environment. The electromagnetic environment with a time domain fluctuation of the electric field the same as the clutter distribution is synthesized in the cavity by changing the settings of RC. The measured data is analyzed by using KS test and BIC. The results show the BIC method makes up for the deficiency of goodness-of-fit tests, and can be used to select the optimal distribution from several candidate distributions. In under-moded (low frequency) conditions of the RC, a clutter with Weibull distribution is synthesized in the RC;in over-moded (high frequency) conditions of the RC, a clutter with Rayleigh distribution will be synthesized.

As an aircraft with special configuration, the tilt tri-rotor UAV combines the advantages of helicopters and fixed-wing aircrafts and has the operating modes of the two at the same time. Whereas, the engine nacelle should be controlled in the transitional mode, which brings the problem of manipulation redundancy, and neither manipulation approach is fit for use alone. In order to solve the problem of aircraft manipulating redundancy of the tilt tri-rotor UAV in the process of nacelle tilting in the transitional mode, an appropriate dynamic model of the tilt tri-rotor in the transitional mode is built, and a new tilting control method based on fuzzy control is proposed. Through the experimental analysis and the comparison with the traditional manipulation strategy of the tilt rotor aircraft in the transitional mode, it is found that this method can solve the problem of longitudinal height control of the tilt tri-rotor UAV in the transitional mode, so that the tilt tri-rotor UAV can implement a smooth and efficient flight in the transitional mode.

Feature extraction and feature matching are two key steps in SAR target recognition. A method for SAR target recognition based on the matching of target regions is proposed. First, the binary target region of SAR image is extracted, which is then compared with the corresponding target region in the template base to produce the residual image. Euclidean distance transform is used to process the residual image, and the processed image is used for constructing a similarity criterion. The matching rate of the image to be identified with each type of target is then calculated out, and the type of target is judged according to the principle of the maximum matching rate. The target region residual can reflect the physical difference of the target to be identified with the other types of targets, and thus we can calculate the matching rate by use of the area and shape distribution of the residual. The change of Euclidean distance can reflect the shape distribution of the target region residual, and the residual based on the Euclidean distance transform can better reflect the matching rate of the target region. Target recognition test was carried out by using MSTAR dataset, and the result verifies the effectiveness of the method.

The typical combat modes of two-fighter cooperation for Air-to-Air Missile (AAM) guidance in target attacking are summarized, and the key realization process of two of the most important cooperative modes is discussed. A contrastive analysis is made to the target indication models of the cooperative launching/guidance and the single-fighter launching/guidance. It is shown that the target indication error in the situation of cooperative guidance is increased. The realization of cooperative guidance is at the expense of some guidance precision, but it can greatly improve the operational efficiency of the fighter planes at the same time.

To carry out automatic path decision-making for the penetration of Unmanned Aerial Vehicles (UAVs) in threat-networked environment, a model for path decision-making is proposed based on Structure-Varied Discrete Dynamic Bayesian Network (SVDDBN). The decision-making model is established according to the mode of UAV passing through the threat area and its response to firepower threat. Then the results of path decision-making are obtained by using the SVDDBN algorithm based on adaptive parameter. The results of simulation show that the model meets the need of path decision-making for UAVs in threat-networked environment and provides a new pattern of thinking for the penetration of UAVs.

In order to identify the number of rotor blades and rotation period parameters of low-altitude multi-rotor UAVsa method of parameter estimation for multi-rotor UAVs based on ISAR sequences was proposed.Euler rotation matrix was used to build a motion model for multi-rotor UAVsand the ISAR imaging mechanism of multi-rotor UAVs was analyzed.Then the ISAR sequence of multi-rotor UAVs was obtained by using the range-instantaneous Doppler algorithm.Through the imaging simulationit was discovered that strong scattering would appear on the imaging surface when the rotor is perpendicular to the radars visual direction.The ISAR data was pre-processedand the distribution matrix of strong scattering in the time-range domain was obtained.Then the number of rotor blades was estimated by using the ant colony algorithmand the rotation period was estimated by autocorrelation.The simulation results show that the proposed method has a good anti-noise performance.The number of rotor blades and the rotation period could be estimated when the SNR was greater than -10 dBand the estimation error of the rotation period was less than 8%.

A new concept of airborne fire control system with distributed collaborative architecture is introduced. This new architecture can realize the following integrated commanding modes easily in theory: accurate target pinpointing, external detection, guidance handover, remote launching of missiles, and attack priority decision-making. Some key technologies for realizing the fire control system are analyzed, including the design of distributed system architecture, distributed information processing, distributed collaborative decision-making, and collaborative attack and guidance. The study can be taken as a reference for future development of the airborne fire control system.

Aiming at the problems in particle filter that the importance density function is difficult to select and the system state covariance matrix may appear negative definiteness, this paper puts forward a new kind of Singular Value Decomposition Unscented Particle Filter(SVDUPF)algorithm. The algorithm adopts adaptive factor to regulate the dynamic model error, uses the singular value decomposition to restrain the negative definiteness of the matrix, and uses the improved UKF algorithm to generate the importance density function, which can make up for the defects of the particle filter. The proposed algorithm is used in the single-variable, non-static state growth model for simulations. The results show that the proposed algorithm has a filtering precision obviously better than that of EKF and UPF algorithm, which can improve the calculating precision of the model.

To solve the problem that the parsing process of the traditional ADS-B message software is complex and difficult to understand, a simple and easy-to-implement analytical method is proposed. First of all, the hexadecimal message data received by the network port is converted into the corresponding 01 character string. Secondly, according to the structure of ADS-B message, the program of CPR algorithm is implemented. Finally, the ADS-B message data is sent in real time via the SBS-3 device network port, and the Qt platform is used to receive and parse the ADS-B message data. The results of actual tests and the comparison with the traditional method show that: 1) The method of the study and the designed parsing procedure can be used to parse the ADS-B message data in real time;and 2) The result is the same as that provided by the SBS-3 device. The experiment proves the effectiveness and feasibility of the proposed method.

The kind of kHz and high-energy pulse laser light source with narrow pulse width has broad prospect in the field of laser ranging. A high-energy, narrow-pulse-width and kHz Q-switching solid laser was designed based on the theory of electro-optical crystal Q-switching and narrow pulse width. A pumping configuration applicable for the high-duty-ratio and high-power LD end face was used in the experiment. The pumping light was focused on the operation material by using the prism coupling system, of which the maximum light conversion rate reached 27%. High-repetition-frequency electro-optical Q-switching effects was made by using RTP crystal and KD*P crystal respectively. With almost the same static input, KD*P crystal Q-switching obtained the dynamic energy output of 11 mJ, while the dynamic energy of RTP crystal was only 5. 64mJ. Under the conditions of optimum pumping power, the dynamic-to-static ratio of KD*P crystal was close to 80%, while the dynamic-to-static ratio of RTP crystal was close to 40%. Finally, by changing the length of the resonant cavity, the feasibility of the short cavity method to achieve the narrow-pulse-width laser output was verified. The narrow-pulse-width laser output of 5. 76ns was obtained for the physical cavity length of 60 mm.

The prediction of flight performance via the analysis of pilots, multiple physiological signals is one of the most noteworthy issues in the area of aviation safety. A flight performance prediction model using Bacterial Foraging Algorithm (BFA) to optimize Generalized Regression Neural Network (GRNN) is proposed to train the pilots, multiple physiological signals, so as to predict the flight performance in simulated flight tests. Through the comparison between the predicted results of the model and the real value of the flight performance, the validity of the proposed method is proved, which provides a new approach to the prediction of flight performance.

Aiming at head posture measurement on the moving platform, an integrated measurement method with faster measuring speed and higher accuracy is put forward. The head posture data obtained respectively by Vision Measurement (VM) and Inertial Measurement (IM) are fused by using the Kalman filter, and the data from the inertial pose measurement is revised by using the vision pose measurement. Therefore, the advantages of VM that the error is not changed with time, and of IM of fast measuring speed and large measuring scope are integrated;while the disadvantage of IM of unlimited and distributed error is restrained, and the shortcomings of VM such as limited measurement range, easily being disturbed, etc. , are overcome. Experimental analysis and simulation results have proved the validity of the method

Structural modal coupling is one of the problems which must be solved in FBW (Fly-By-Wire) control law design. Firstly, the advanced technologies of foreign civil aircrafts are analyzed. Then, the design methods of structural notch filter and structural modal suppression and the issues that should be taken into consideration in the design are researched. The feasibility of the method is verified by using an example aircraft. Finally, the principles and methods of ground tests are described briefly.

The bat algorithm is introduced to solve the NP problem in multi-sensor multi-target allocation. By applying the method of K-means for initializing the algorithm, adopting the adaptive step length for updating the speed, searching in the opposite direction and dissociating, the basic bat algorithm is improved. A simulation is made and the result shows that: 1) Compared with the basic bat algorithm, the improved bat algorithm has faster calculation speed and better optimizing capability; and 2) Compared with the particle swarm algorithm, the artificial bee colony algorithm, and the wolf algorithm, the improved bat algorithm is the most adaptive to the problem of multi-sensor multi-target allocation, and can obtain the best solution.

Considering that the Store Management System (SMS) is becoming more and more complicated, we used the method of Model-Based Systems Engineering (MBSE) in the development of SMS for the first time. With the Harmony method, and by use of such tools as DOORS and Rhapsody, we made requirement analysis, system function analysis, architecture analysis and design of a system, obtained a series of use case models and interfaces, and implemented the validation of requirements and analysis of the system. Compared with the traditional design method taking documents as the center, the MBSE based method verifies and traces the requirements more adequately, and is able to avoid iterative designs caused by departure from the requirements, and thus the development efficiency can be improved.

The problem of multi-target tracking by double-satellite cooperative detecting is studied. Firstly, the observability is analyzed according to the detecting geometry of two satellites. And the state equations and measurement equations of powered phase are established according to the turning model based on gravity. Secondly, to solve the problem of flight path tracking abnormity in the situation of multi-target tracking, an SME filter algorithm based on binary polynomial, called BPGM-SME, is put forward. In order to improve the accuracy and convergence rate of single-target tracking, an improved UKF algorithm based on iteration is given. Finally, the simulation indicates that: 1) The BPGM-SME algorithm has fine tracking performance for multi-target tracking;and 2) In single-target tracking, the improved UKF has better convergence effect and tracking accuracy than that of the original UKF.