In order to achieve highprecision tracking of highspeed glide vehicle, a tracking algorithm for hypersonic jump-gliding maneuvering targets in the near space is proposed. Its core is based on the SW (Sine Wave) model, which combines the digraph switching principle with the interactive multi-model algorithm to achieve the adaptation of the model set. In order to cover the change of the periodic maneuvering angular velocity, the cubature Kalman filtering method is used to design the filter. The simulation experiment is compared with SW single model and SW interactive multi-model to verify the superiority of the proposed algorithm when tracking the hypersonic jump-gliding maneuvering target in near space and the effectiveness of model set switching.

In order to improve the target destruction by the missile and achieve successful interception of the target in a bounded finite time, a terminal angle constraint sliding mode guidance law based on fixed-time convergence is proposed. Firstly, a plane guidance system model of missile intercepting target is established, and the target maneuver is regarded as unknown bounded disturbance. Secondly, a fixed time disturbance observer is used to observe the disturbance of the guidance system. Thirdly, the terminal angle constraint guidance law is designed based on fixedtime convergence sliding mode control and fixed-time disturbance observers. The fixed-time stability of the guidance system is proved, and the convergence domains of guidance system states are given. Finally, it is verified that the designed guidance law can achieve intercepting the target at a specified angle while ensuring accurate interception via numerical simulations.

Multi-agent-based cooperative guidance usually uses particle acceleration as a control input. This model is not compatible with tactical missiles that usually perform unpowered flight in the terminal guidance phase. In this paper, under the leaderfollower missile formation structure, firstly, a distributed nonlinear cooperative guidance law design model for the second-order line-of-sight angle of the target-missile with rudder deflection angle as input is established; secondly, based on sliding mode control and disturbance observer, a finite-time guidance law of the leader missile with line-of-sight angle constraint for the precise strike of the moving target is designed. Thirdly, a distributed discontinuous cooperative guidance law is proposed for the follower missiles, and the adaptive law of its parameters is given. The system stability is proved by Lyapunov theory. Mathematical simulation results show that the method designed in this paper can achieve the consistency of the follower-target LOS angle and the leader-target LOS angle, and finally achieve a precise and coordinated attack on the moving target.

Combined with the development of deep learning, using deep convolution network model, this paper integrates feature extraction and target recognition into one model, so that the system can automatically extract target features and give category decisions. Denoising is usually needed for images with low signal-to-noise ratio, but the denoising ability is not proportional to the accuracy of detection and recognition. The denoising method adopted in this paper not only improves the image quality, but also effectively improves the recognition accuracy. It avoids the reduction of accuracy caused by the loss of details. At the same time, in order to further improve the recognition effect of low SNR images, a super-resolution network based on Convolutional Neural Networks (CNN) is used to provide conditions for obtaining more feature information. In addition, in order to solve the problem of incomplete data sets, some research on the sparse azimuth of MSTAR data sets is made, which can maintain a high recognition rate under the condition of fewer training samples.

Precision guidance weapons play an important role in modern war. In this paper, basic concepts and roles of precision guidance weapons, precision guidance systems and precision guidance technologies are introduced briefly. The developing requirements for future precision homing terminal guidance system and technology are reviewed. Furthermore, possible approaches to meet the requirements of future precision homing terminal guidance system are introduced. And the challenges for the realization of future precision homing terminal guidance system are analyzed. 

When using relevant parameters for polarimetric synthetic aperture radar (SAR) targets detection, it is difficult to remove the strong reflectors such as ground clutter and buildings. To solve this problem, Span is introduced to describe the backscatter power of the target. First, extract the polarization feature parameters, then use the correlation coefficient classifier to generate potential targets, and finally use Span for distance discrimination. The experiment results show that this method can effectively eliminate the above mentioned interference and achieve the vehicle targets detection task in complex ground environment. In addition, by comprehensively comparing the application of correlation coefficients in the SAR targets detection, it is found that the similarity parameter is more effective than other polarimetric SAR feature parameters.

This paper presents a new distributed clustering method for cooperative sensing to solve the problem of multi-target information processing under the condition of decentralized cooperative sensing. Firstly, it formulates a new mathematical model for consensus class center computation with locally averaged data. Secondly, it enables all the sensing equipment to compute in parallel and exchange only the information with its neighboring nodes to protect the privacy of the captured data. Finally, all the equipment obtain the consensus class center and the clustering results when the network is stable. The experiment results prove that the distributed clustering method can make full use of the store, computation, and communication ability of the equipment to complete the clustering task without exchanging massive data. 

This paper proposes an information fusion method for multi-missile multi-target cooperative detection based on radar seeker. In order to complete the multi-target collaborative detection and target association task, based on the target association JPDA algorithm and the use of interactive multimodel (IMM), a fusion model suitable for highly maneuverable target tracking is given, and a simulation system is established. For the flight schemes with different angles and distances between the missiles, the simulation analysis of the target tracking performance is carried out. The simulation results show that the collaborative detection target association information fusion method presented in this paper effectively improves the accuracy of multi-target tracking and can be used for multi-missile cooperative target detection. 

In this paper, a sliding mode guidance law is designed for intercepting high speed and large maneuvering targets. A new error variable function is designed by combining the line of sight tracking error with the performance constraint function, so as to ensure that the line of sight angle of the guidance system can converge to the desired angle; the convergence speed of the line of sight angle is not less than the preset speed; and the maximum overshoot and convergence precision can satisfy the prescribed performance. The key concept in this approach is to transform the performance constraint problem into the bounded problem of the error variable function. In addition, the adaptive guidance law is designed to ensure the stability of the guidance system in the case of known upper bound and unknown upper bound. Simulation results show that the designed guidance law has good performance.

This paper describes a kind of motion estimation algorithm for detecting low-altitude slow and small target (LSS-target) in heavy clutter environment. The algorithm combines 2-D fast Fourier transform (2-D FFT) and time-frequency analysis to analyze target's echo, and calculates the correlation coefficient of target and heavy clutter environment to detect motionless target. After aforementioned procedure, a time-velocity/range image of the target in heavy clutter environment is obtained. The results of time-frequency analysis and correlation coefficient calculation are used in range extrapolation to calculate low-acceleration target's range information. The feasibility of the algorithm put forward in this paper is verified in an experiment.

In order to give full consideration to multiple scattering of ship target and its coupling with the surface scattering, this paper uses the high frequency mixing method to study the composite scattering of the sea and the ship target by adopting the physical optics method to approximately simulate the electromagnetic scattering of sea surface, and by using the shooting and bouncing ray method to estimate the target electromagnetic scattering and its coupling with the electromagnetic scattering of sea surface. In this paper, two ship models with different structures are selected as simulation examples, and the electromagnetic scattering results of the ship models and their composite models with see surface under different radar parameters are calculated. The simulation results show that this method can estimate the coupling scattering between complex structures of targets, and the simulation results are more reliable than the simple physical optics method. And the scattering results can provide a lot of reliable training data for the future research of ship target classification and recognition based on machine learning.

The paper proposes a cooperative guidance law with constraints on guidance time and attack angle in twodimension plane, which can improve the penetration ability and combat effectiveness of multi-missile systems and  adapt to the complex and changeable future warfare. By applying the second-order sliding mode control theory and using the backstepping method to ensure the stability of the system, through setting the trajectory of the expected attack angle, the cooperative guidance law with multiple constraints is derived. The guidance law is simulated under the condition that the target is stationary or moving. The guidance law can complete the cooperative guidance task with time and angle constraints within a certain limit range of lateral acceleration.

By using the Gaussian pseudo spectral method, the optimization of the farthest lateral glide trajectory of spacebased reentry vehicles is studied, and aerodynamic modeling methods are proposed for axisymmetric aircraft dynamics models. A Gaussian pseudo spectral method is used to establish a nonlinear optimization problem, and an analytical Jacobian matrix solution method is given. Under various path constraints, the trajectory optimization simulation is performed using the lateral glide distance as the performance index. Simulation results show that this method can effectively solve the optimization of the farthest lateral glide trajectory of spacebased reentry vehicles.

For an agile missile that uses direct lateral force provided by engine plume, under the constraints of turning rapidity, missile speed, expected speed angle and expected attitude angle, this paper designs a turning law employing the optimal axis control principle, the fastest turning rate principle, and the conditions of missile speed limit. Simulation results show that this turning law realizes the turning speed and the turning attitude of the missile, and can guarantee the speed of the missile in flight.

Due to the characteristics of hypersonic morphing aircrafts, such as fast flight speed and wide range of flight altitude, the dynamic model parameters of hypersonic aircrafts are highly uncertain. Therefore, it is necessary to study the online identification method of unknown parameters in the dynamic model of hypersonic morphing aircrafts. In this paper, based on the analysis of the characteristics of flying hypersonic morphing vehicles, the longitudinal small disturbance linear motion equation is selected as the identification model. The recursive least square method is used to identify the parameters of the linear subsystem in the linear motion model of multiple input multiple output (MIMO) systems. The simulation results show that the recursive least square method has high efficiency, fast convergence and high identification accuracy.

A missile with a lateral direct force device based on hybrid Bang-bang control under disturbance is designed for flight attitude control under large angle of attack during agile turn of air-to-air missile. Based on hybrid Bang-bang control under large angle of attack flight condition, an ESO (extended state observer) is used to compensate the uncertainty of aerodynamics in order to improve robustness. At the same time, Runge-Kutta is used to solve the limit cycle caused by delay to improve control accuracy. The asymptotically stabilization of the control method based on ESO is proved and the condition is given. The simulation result shows that the control method can help the missile complete the agile turn under different disturbance induced by aerodynamics and lateral thrust.

This paper mainly aims at the design of an adaptive backstepping attitude control system for longrange missile with bounded external interference. Firstly, the state space model of attitude control system of missile is established. Considering the problem of attitude singularity, the model based on Euler Angle is transformed into the missile rigid body kinematic model based on quaternion, and then the attitude error dynamic equation is established. In order to improve the reliability of attitude control system, an adaptive backstepping attitude control law is designed against the external interference. The likely interference is handled through adaptive estimation and compensation for the uncertainties. The stability of the algorithm is analyzed based on Lyapunov function method. Finally, the method is verified by simulation and the results show that this control method has good robustness and control accuracy.

This paper aims at the problem of how to improve the navigation and positioning accuracy of the inertial navigation system without satellite navigation and positioning systems, and proposes a navigation error estimation technology based on distance measurement information of aircraft three-dimensional network. By using the inter-aircraft distance measurement information to correct the navigation error of the inertial navigation system, it can significantly improve the navigation and positioning accuracy of the aircraft in the three-dimensional network. First, analyze the principles of aircraft three-dimensional networking navigation, design a system technical plan, and set a navigation effect evaluation method. Second, design a three-dimensional distance measurement navigation error estimation algorithm and build a settlement model. Finally, simulation verification is performed. The simulation results show that: for a network composed of 4 aircrafts, when the distance measurement error is 20 m, after 10 minutes of network navigation flight, the inertial navigation position error can be increased by more than 2 times; when the network also includes a highprecision integrated navigation correction station, after 10 minutes of networking navigation flight, the inertial navigation position error of the aircraft can be increased by an order of magnitude, which verifies the feasibility of the technology.

The dynamic base alignment technique is often used for initial alignment when airborne tactical weapons are launched. The deflection of wing is an important factor affecting the alignment performance. In this paper, a cantilever beam vibration model of the wing is simplified as a second-order stochastic process model, and the stochastic process model is expanded to the filter state quantity for estimation. Compared with the traditional high-dimensional filter, the filter state is reasonably reduced, and the high-dimensional filter is simplified. The simulation results show that the stochastic process model can well compensate the influence of the dynamic deformation of the wing on the performance of the filter. The filter can also estimate and track the dynamic deformation angle well, and can be used to compensate the wing deflection effect; under the condition that the alignment accuracy cannot be affected, the simplified filter has less calculation and is more suitable for engineering implementation than the highdimensional filter.