Abstract:In order to quantitatively analyze and evaluate the longdistance guidance effectiveness of the Early Warning Aircraft steering the fighter, the longdistance guidance successful probability is taken as an index for describing the guidance effectiveness, and a mathematic model is built up based on analyzing the course of the Early Warning Aircraft steering the fighter. And the course of longdistance guidance is divided into level guidance and vertical guidance, error analysis models of the level guidance and the vertical guidance are built up according to the parallel approach guidance rule, and the algorithms for longdistance guidance effectiveness are put forward by using probability analysis method, through the algorithm the relations are acquired between the longdistance guidance effectiveness and some factors such as guidance error, the fighter radar capability and target characteristic. Under the scene of the fighter lower speed than the target, an example of a fighter intercepting a target by the Early Warning Aircraft's longdistance guidance is given to analyze effect rules of primary parameters on longdistance guidance probability, including target enter angle, intercept distances, antenna scan area and target parameters precision. Through simulation the results efficiency approaches are presented for increasing the longdistance guidance effectiveness based on this scene

Abstract:Aimed at that longitudinal hypersonic vehicle model has some features such as high nonlinearity, multivariable coupling and parameter uncertainty, etc., a new dynamic surface sliding mode control scheme for hypersonic aircraft based on nonlinear disturbance observer is proposed. In the scheme nonlinear disturbance observer is used for observing the unknown nonlinear disturbance and the observer is in exponential convergence by selecting the design parameters, then the dynamic surface sliding mode control is designed, and the proposed control scheme can be adopted to guarantee the semiconsistent and stable global system. Simulation results demonstrate that the use of the proposed control scheme can effectively overcome the nonlinear disturbance and enhance the robust performance of the system

Abstract:Aimed at the problem that the tradition effectiveness evaluation method is not suit to the modern Beyond Visual Range (BVR) air combat and combined with the characteristic of command and guide in BVR air combat, a new effectiveness evaluation model of command and guide in BVR air combat is proposed. The model is used to proceed from the analysis of the destination situation of command and guide, and select the three factors angle，distance and energy as the evaluation indexes of the command and guide situation. And then by comprehensively taking the influence of radar detection distance and the airtoair missile shoot distance on command and guide into consideration, the corresponding superiority exponentials are separately established and the weight of each index is confirmed through analytical hierarchy process. Finally an effectiveness function of command and guide in BVR air combat is obtained by use of the weighted synthetic assessment method. The effectiveness of the model is verified by situation results

Abstract:The aviation process of multiplane combat with data link system is studied in this paper. Based on the logarithmic method, a calculation method of air combat effectiveness assessment supported by data link is given and is converted to the average battle effectiveness level which is verified to be equivalent to and consistent with the air combat effectiveness assessment by mathematic theory. Based upon the improved Lanchester equation air combat model which reflects the data link function, a Lanchester air combat model under multiplaneconflict condition is set up. Based upon the four preset air combat processes and two multiplanecombat scenarios and with the examples of doubleplane confrontation, the air combat process under four different circumstances are simulated and analyzed. Further analysis is made on the influence data link on multiplane air combat, which provides the simulation data and the exhaustion chart. The result shows that under the data link can improve combat effectiveness and reverse the combat result. Moreover, the doubleplaneaircombat effectiveness is raised by about thirtyfive percent.

Abstract:A modified Weibull distribution model is proposed for aviation equipment generally obeyed Ushape curve, which is more standard than exponential distribution and Weibull distribution. The Maximums Likelihood Estimation (MLE) for point estimation and confidence interval estimation method are deducted under progressively typeII censored data. Furthermore, according to the algorithm of the percentile bootstrap method an example based on matching a set of failure data is given to obtain the results of point estimation and confidence interval estimation under modified Weibull distribution. And through the comparison between bootstrap method and Bayes method, the results show that the bootstrap method is more accurate and can be simpler under the same confidence level, which provides an available theoretical analysis method for the problem of reliability estimation under progressively typeII censored plan

Abstract:With the widely application of the Multi-platform and Multi-sensor in the Air Combat Rivalry Evaluation, the accomplishment of the better data Pre-processing of Multi-platform Air Combat Rivalry Evaluation will play a vital role in route selection、 track fusion、 evaluation and prediction of real -time and afterwards air combat training. Through building multi-platform air combat training evaluation system, the measuring data from varied platforms is analyzed. The Least Square method and coordinate transformation are adopted to realize the time and space registration between varied platforms, the process accumulated error is analyzed and disposed based on the Gaussian Sum Estimate Kalman Filter algorithm. Simulation analysis is done, the result shows that the matched curve between measurement track and real track is good in fitting result after filter processing, and the purpose of perfecting the Pre-processing of multi-platform air combat rivalry evaluation is achieved.

Abstract:The model of micro-motion targets of Symmetrical Triangular LFMCW (STLFMCW) radar is provided. Based on the micro-motion model, the characteristics of the echoed signal are analyzed and the form of the micro-Doppler signal is obtained. The phenomenon that the micro-motion target's continuous moving during the scan period will induce the widening and deviation of micro-Doppler curves is discussed. To solve this problem, a method for removing the widening and deviation of the micro-Doppler curves is proposed. The echo phases can be compensated by using this method. Then, the parameters of micro-motion target are extracted by the extended Hough transform. The simulation experiment validates the effectiveness of the proposed method.

Abstract:Passive sensor cueing of Active Electronically Scanned Array (AESA) radar searching on specified regions is an important application form of airborne multi-sensor cooperating. In comprehensive consideration of the cueing sensor observation error and target's velocity error, a successful cueing probability density model is established. An optimized target searching strategy satisfied the requirement of timeliness, successful cueing probability and false cueing probability is presented. The searching strategy and performance index are calculated under multi-scenario by using the stepwise optimization method. The simulation result shows that in comparison with the traditional method the proposed method can meet the requirements of successful cueing probability, through increase little beam positions and simultaneously can decrease the false hand-off probability obviously.

Abstract:Against the shortcomings of hardware in data processing and of software in real-time performance, LZW algorithm is optimized and implemented in FPGA in the bulk-storage memory and lossless transmission process. Based on analyzing LZW algorithm, the calculation method is optimized in three aspects. The optimization is inspected and verified by simulation. The results show that the use of optimized LZW algorithm can deliver data compression execution speed and efficiency.

Abstract:In radar usually the side-lobe blanking system is adopted to eliminate pulse-type interference from side-lobe. But SLB system also results in detection-loss. In order to solve this problem, this paper establishes a model of SLB system, studies the cause of the detection-loss resulting from SLB system, gives the definition for the detection-loss probability and derives the equation of the detection-loss probability based on non-central chi-square distribution. The equation illustrates that the radar detection threshold, antenna gain parameters, blanking threshold, mean SNR all can influence the detection-loss probability. The theoretical analysis and simulation proves that different blanking thresholds will result in different outcomes. At last, fix on an optimum blanking threshold is fixed on to reduce the probability and eliminate interference well, and a simulation is done to verify the importance of the conclusion.

Abstract:Optimal evasion from guided missiles is crucial for the subsistence of fighters in air combat. Based on the radar seeker system characteristics of automatic angle tracking system, the tracking error production mechanism is researched, and a maneuver control objective of avoiding the missile attack is put forward. Taking the missile attacking on two-dimensional plane for example, the pursuit-evasion models of the missile and the fighter are built up. And then, the analytical form of evasive maneuver control law is derived based on nonlinear dynamic inversion. The simulation results show that the effectiveness of the above designed method is verified

Abstract:To make full use of the sparse multipath transmission characteristics of the channel when transform domain communication system is in the high-speed wireless transmission status and improve the channel estimation accuracy of TDCS, a compressed sensing sparse channel estimation method is proposed for TDCS.A pilot pattern is designed for TDCS ,the data frame by it maintains the orthogonality between TDCS signals and the main user meanwhile the measurement matrix has weak mutual coherence , then the channel impulse response is reconstructed by the method of Dantzig Selector. Simulations based on COST207 rural area channel model show that the use of new algorithm can effectively reduce the mean square error of the sparse channel estimation and get 1dB performance gain compared with the least square estimation algorithm when the bit error rate is 0.002.

Abstract:To address the problem that neighbor table of greedy geographical routing protocols can not accurately list positions of nodes, which resulted from periodic beacon exchange in unmanned aerial vehicle(UAV) ad hoc network. a mobility prediction greedy perimeter stateless routing protocol (MP-GPSR) is proposed. In the proposed protocol, the next hop is chosen according to the mobility location of neighbor nodes and link expiration time during the routing discovery phase, which slows down the adverse effect caused by the high speed moving of mode. Simultaneously choosing the next hop with the position information of the 2-hop neighbors when the routing void appears can reduce the redundancy of perimeter forwarding. Simulation result shows that the proposed protocol has high packet success delivery ratio and low average end-to-end delay as well as control consumption.

Abstract:The complex operational environment makes the network topology and channel environment complex and volatile, which brings challenges to the maintenance of aeronautical network connectivity. In order to satisfy the demand for network connectivity of aeronautical network, a dynamic relaying protocol based on status information for aeronautical network is proposed, and Exata network emulator is used to analyze the performance of the proposed protocol. By comparing the throughput performance between two aeronautical platform away from each other in three kinds of the aeronautical network without relaying, with fixed relaying, and with the proposed relaying protocol, the use of the proposed protocol can achieve better performance of the network throughput, which means that the proposed protocol is good in maintaining the aeronautical network connectivity.

Abstract:Object tracking using single feature often leads to a poor robustness. In this paper, an object tracking algorithm using multi-feature fusion based on background-weighting is presented. In order to enhance the important features, the target model is background weighting while tracking to get an accurate color model of the object. Meanwhile, special histogram is used to obtain spatial layout of these colors for the target. These features are rationally fused in the framework of Particle filter. Uncertainty measurement method is then introduced into features fusion to adjust the relative contributions of different features adaptively, and the robustness of the algorithm is significantly enhanced. Experimental results indicate that the proposed algorithm is more robust and has good performance in complex scene. The use of the algorithm improves the accuracy of tracking and can track objects effectively even with similar color disturbance.

Abstract:The solution of resource allocation is a significant issue in cognitive wireless network. For minimizing total power of second users, an subcarrier allocation algorithm of multi-colony adaptive immune optimization in NC-OFDM system is proposed. The basic idea and processes of multi-colony adaptive immune algorithm are given. And suitable adaptive operators are designed to speed up the convergence rate and simultaneously avoid the remaining local optimal. The simulation results show that the use of the algorithm can advance 20 percent in the reach of convergence state and make the total power of whole system decline 10 percent, and so it is an efficient subcarrier allocation algorithm of fast convergence speed.

Abstract:In this paper, the platform resource scheduling problem has been carefully studied. Aimed at the DLS that is liable to plunge into local optima, this paper presents an approach to solving the problem based on the dynamic list scheduling (DLS) and niche genetic algorithm (NGA). Task intense is introduced to describe the dynamic loss of the platform capacity in the process of combat. By taking the finish-time of mission as an index and on the premise of guaranteeing the platform resource utilization ratio, the NGA with overall importance is adopted to get the best approach to platform resource scheduling. Finally, through a case of joint campaign, a conclusion is obtained that the use of proposed approach can make the mission finished in short time, which provides a basis for battlefield resource scheduling.

Abstract:To resolve the problems of revocation under the quantum computing, combined with Zhang's scheme, the paper constructs an attributed-based encryption which is revocable from lattice. This scheme updates the key which is associated with un-revocable attributes under the binary tree structure. By using the idea of Shamir's threshold secret sharing scheme, a threshold access policy is realized in this paper. The scheme is selectively secure where the security is reduced to the hardness of learning with error problems in the random oracle model. The analysis shows that the scheme is secure under the quantum attack and supports the flexible threshold access policy.

Abstract:In this paper, according to the characteristics of CML2 system,a kind of system configuration design method is put forward based on XSLT technology. It is mainly based on the model driven architecture design patterns, to transfer the system configuration development core to the model, get the final system configuration through the conversion between model and code generation technology, semantic constraint model using XSD .Through the XSL language to convert the target file,It is ready to use software configuration method of software component of the "plug and play"in different platform, easy to maintain and operate.