Since Out-of-Sequence Measurement(OOSM) problem may occur in target tracking system, a filtering algorithm using covariance intersection was proposed to solve the problem on the basis of forward prediction.Based on forward prediction, a reconstructed track containing delay measurement information was established.Then the covariance intersection method was applied to fuse the reconstructed track with the existing track to achieve the update again.Through adopting information filter and covariance intersection method, the complex operations, such as calculating the inverse of state transition matrix and track correlation, were not needed again.The new algorithm can deal with both the one-step-lag and multi-step-lag OOSM situations.Theoretical analysis and simulation results show that the new algorithm achieves better real-time performance with less storage and computation cost while keeping the filtering precision.

The real-time performance of a scheduling method should also be regarded as one of the main goals in avionics data bus test equipment in which the real-time property of messages is highly demanded.A dynamic multi-objective particle swarm optimization algorithm is proposed, in which elitism archived strategy is used, to optimize the message queue in the objectives of maximizing the available scheduling time and balancing the bus load.The Pareto front and a non-dominated solution set are obtained.The validity and rapidity of the method are verified through simulation and a message queue is generated, which satisfies the demand of high real-time property and the balance of bus load.

A novel method for time synchronization of bistatic radar system is put forward based on two-way time transfer via troposphere scattering (TWT3S).In order to get accurate time difference of the radar stations, the troposphere scattering communication equipments are employed to contrast bilateral time signals.Firstly, the calculation model of TWT3S is deduced in detail.Then the time interval measurement error, the launching and receiving device delay error, the tropospheric delay error and the geometrical distance error are studied.Finally, theoretical precision of TWT3S is presented.The computational results demonstrate that tropospheric delay error is the main error, which accounts for more than 90% of all errors.Further more, theoretical precision of TWT3S system is 15~21 ns, and obviously it has a better performance compared with the direct synchronization method via microwave or optical fiber channel.The work provides a new way for time synchronization of bistatic radar system.

Conventional Voronoi diagram can only be used in route planning with the same threats, which is limited in application for actual battlefield environment.We proposed an improved Voronoi diagram based on Delaunay triangulation, and applied it to route planning with different threats.The construction of the improved Voronoi, the obtaining of starting path and ending path were mainly discussed in the paper.Finally the route planning based on the improved Voronoi was completed on the platform of VC++6.0.The result shows that the planned route can effectively avoid the threats as radars, which proves the feasibility of the improved Voronoi in route planning with different threats.

To study the integrated management of jamming resources in time-sharing and multi-target interference systems onboard advanced fighters, the target threat evaluation model was built up by the multi-attribute decision-making method.Compromise sorting method was used to process partial order of target threat and reintegrate interference task request queue.The limitations of interference resource were analyzed comprehensively from the four aspects as space, frequency, energy and time, and quantitative descriptions were given on the effect of interference.An algorithm for jamming resource management in time-sharing and multi-target interference systems was proposed in the end.After processing partial order, the efficiency of interference systems and the degree of intelligence in interference systems are improved by the reintegrated interference task request queue and the control of interfere time and parameters.

A rugged LCD has to pass the high-temperature environmental test to make sure that the LCD can still work even when the ambient temperature is high.A finite element analysis model of a rugged LCD was established in the paper.A rugged LCD was tested to get the temperature distribution.Based on the comparison of simulation results and practical results, the model was optimized and the precision of the simulation results were guaranteed.The temperatures of LCD and LED backlight board at different ambient temperatures and with different drive currents were simulated.The results show that when the ambient temperature reaches 65 ℃, the drive current should be lowered to 150 mA to make sure that the temperature of the LCD is below the LC clear point and the joint temperature of LED is not higher than the maximum limited value.

The sliding mode control with unidirectional auxiliary surfaces (UAS-SMC) based on the power reaching law was used for a class of nonlinear continuous systems.According to the nonlinear continuous system, a UAS-SMC was designed.On which basis, the power reaching law was introduced, and a UAS-SMC based on power reaching law was developed.Then, theoretical analysis proved that the system states will converge on the switching surfaces in a finite time and it is stable.The simulation results show that the chattering can be effectively reduced, and the method ensures the reaching speed near the switching surfaces.The reaching law is zero if and only if the system states are zero.

According to the maneuvering of an Unmanned Aerial Vehicle (UAV) when escaping from the attack of pure proportional guidance air-to-air missile, the pursuit-evasion mathematic models of the UAV and the missile were built up in three-dimensional space.The potential fields of the UAV and missile were analyzed by using artificial potential field theory.The situation model, pointing to the fastest increasing direction of UAV combat power potential, was established.A new combined escape guidance law was formed based on anti-proportional navigation guidance and anti-tail potential field power.Simulation was made for the cases of head-on attack scenario and stern attack scenario.The results indicate that the guidance law can complete escaping task effectively.

After analyzing the invalid mapping and the poor real-time performance in batching voting of the classical Hough Transform (HT) in parameter space mapping method, an improved HT detection algorithm was proposed on the basis of converging mapping of the aerial target velocity constraint sampling and online voting.The simulation results show that the improved target track detection algorithm achieves better performance while SNR is greater than 0.8 dB, and the target acquisition time varies with different SNR.The target can be captured quickly when SNR is high, and we can use time to exchange for the probability of detection when it is low.

The UAVs have limited detection range and can carry limited consumable payloads.Therefore, when it requires different types and different quantities of payloads to completely destroy a detected target, a team of UAVs, called a formation, is needed.A multi-UAV formation for taking search and strike mission was proposed, which ensured the minimum delay of target attacking and the minimum scale of formation through two phases.Three search strategies:random search strategy, multi-lane based search strategy and grid based search strategy, were given.At last,Monte-Carlo simulation was used to implement the formation algorithm and analyze the performance of three search strategies.

When used in atmospheric probing, a K-band hyperspectral microwave radiometer can improve the accuracy of temperature and moisture profiling under high humidity condition.But the measuring time is longer and system complexity of traditional radiometer receiver is relatively larger under hyperspectral microwave condition.An ultra-wideband multichannel linear receiver was designed.By combining several advantages of traditional microwave radiometer receiver, the proposed receiver architecture has good wideband performance, high linearity, and short measuring time.At 18 to 26 GHz RF, the performance of measured receiver has a power gain of 77 to 80 dB, a noise factor of 2.1 to 3.2 dB, a linearity of 0.999 to 0.9999, and a multichannel measuring time of 5.8 ms.The measurement results show that the proposed receiver is suitable for K-band hyperspectral microwave radiometer applications.

The inertial navigation system (INS) of ships switches between two modes of undamped navigation and horizontal-damped navigation according to the state of motion, during which the system error caused by the acceleration of the ship and the overshoot error resulted from the frequent switches between two modes may degrade the dynamic performance of the INS.Considering the limitations of traditional damping method, the adaptive control method was applied to design a level damping network of platform inertial navigation.The damping network parameters were changed adaptively according to the acceleration, thus to make the system error minimum.And a method for restraining the overshoot error caused by mode switching was also proposed.Theoretical analysis and simulation result shows that the method can improve the dynamic performance of the INS effectively.

In study on the launching position for TV-command guidance missiles, we proposed an optimization method for lessening the optimizing space with multiple threats.The constraints of launching position were analyzed, and the dynamic and static threat models of the missile operational area were established.Then, the optimization guideline of launching position was put forwarded, and the optimization model was established.Numeric simulation was made based on particle swam optimization (POS).The simulation result proved the effectiveness of the model and method, which has great application value and is of important significance for the operational planning of missiles.

Since the nonlinear model of guided projectile has uncertain aerodynamic parameters, modeling errors and external input interference, a robust adaptive controller was designed for the guided projectile based on dynamic surface.The problem of “explosion of complexity” in traditional backstepping approach was solved by introducing the first-order low pass filters and obtaining the differential of the virtual control inputs.The effect of uncertain parameters of the model was cancelled out by the robust function, and the external disturbances was eliminated with the nonlinear damping items.Finally, the closed-loop system was proved by Lyapunov function to be semi-global stability.The design method is simple and the limiting conditions of uncertainty was relaxed while making effective use of the given information, and the trajectory error can be adjusted by the parameters of controller.Simulation results show the availability of this method.

In order to improve the tracking performance of airborne electro-optical tracking and pointing platform, fuzzy control was used together with PID control.The adaptability of the Fuzzy PID controller was improved by changing the fuzzy input and output variables, thus can enhance control performance of the airborne electro-optical tracking and pointing platform.Simulation results show that the method has preferable robustness, and can decrease overshoot, shorten response time and improve control accuracy.

For the purpose of detecting and locating faults in time during the running of adaptive optical wave-front processor based on Field Programmable Gate Arrays (FPGAs), a fault diagnostic system (FDS) is proposed for this wave-front processor.According to the requirements of debugging and operating, the system can provide real-time feedback of the results and states from each part of the wave-front processor to upper PC, locate faults, and analyze data error.The fault diagnostic system was tested on 137-unit adaptive optical wave-front processor platform.Experimental results indicate that the feedback data from the monitor system and the relevant information are pretty matched with the corresponding theoretical values, and FDS can also detect and locate the faults in time, during the real-time correction of the processor.The system is applied in the large foundation of high resolution imaging telescope adaptive optical system, which is able to reflect the process and relevant results of the adaptive optical wave-front processor intuitively, detect and locate the source of faults in time if faults occur, and greatly improve the testing efficiency in both hardware and software.Meanwhile, analyzing the results from each stage contributes to improve the calculation speed and precision.

A holographic waveguide display system using twice prisms for coupled input was proposed.The working principle of this system was introduced, the achromatic principle of the twice prism coupled input was designed and analyzed, and simulation analysis on the model was presented.The simulation results demonstrate that the system processes a FOV of 24°×20°, an exit pupil diameter of 40 mm, the distortion is less than 2%, and the MTF is higher than 0.7 at the spatial frequency of 30 lp/mm across the entire FOV, which satisfes the requirements of an optical imaging system.

Due to their flexibility in dynamic structural adjustment, Static Random Access Memory (SRAM) based Field Programmable Gate Arrays (FPGAs) are widely applied in industry and other fields.Aimed at the layout problem of modules on the reconfigurable functional unit, a hierarchical circuit partitioning-based timing-driven placement algorithm was proposed based on analysis to the limitation of the simulated annealing algorithm.The circuit was first divided into limited number of tiers based on principle of minimum cut, and then the layout of each tier was implemented according to top-down principle.The algorithm can also attain the minimum critical path delay.Experimental results show that:compared VPR algorithm, the proposed algorithm achieves better results in delay, wire-length and runtime.

Since the influences of ambient magnetic field and manufacturing process are not taken into consideration in an electromagnetic positioning system, the positioning precision of the system may decrease.This paper presents a method to improve the positioning precision of the electromagnetic positioning system.To overcome the shortcoming that the classical magnetic dipole model is too ideal, an error correction model was proposed.The antenna calibration theory was presented, the calibration method, correction factor, calibration process and device were given.Comparative experiments show that the precision of the improved system positioning model is 5 times of the uncorrected one.

Considering the different requirements to 3D visual software of electronic warfare, the design of an adaptive software architecture was put forward.After studying the change of domain requirements, we proposed a method for demand abstraction and analysis, and designed an adaptive software architecture of 3D visual software for electronic warfare.The requirement processing, corresponding relation of requirement with architecture, and logical architecture were described concretely.In addition, the system expanded application method was given through the structure adjustment when the demand changes, which shows that the adaptive architecture can response to the changing requirements quickly, shorten the development cycle and reduce development costs.

TACAN video signal based on Intermediate Frequency (IF) digital technique is a discrete Pulse Amplitude Modulation (PAM) signal, which contains plenty of random filling pulses with large duty ratio.Considering that the envelope extraction method through searching the pulse peaks is not effective at low SNR, a novel method of digital envelope detection was proposed.According to the definitive signal format, a matched filter was designed to determine the arrival time of pulse by detecting the maximum correlation peak.The pulse peak was estimated to get the envelop signal by fitting the whole pulse.Secondly, least square algorithm was used to estimate the bearing parameter.In order to reduce and restrain outliers, intolerable errors were eliminated on the basis of confidence through residual analysis.At last, the final result was obtained by smoothing acquired k bearing parameters.Its effectiveness was verified by the experiment results.Under the power SNR of 0 dB, the estimation error is less than 0.5°, which meets the requirement of TACAN system.