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Xiao G.,Shanghai JiaoTong University | Yun X.,Shanghai JiaoTong University | Wu J.,Science and Technology on Avionics Integration Laboratory
Science China Information Sciences | Year: 2012

Traditional target tracking algorithms based on single sensor images are unstable and have low accuracy. Based on regional target detection and fuzzy region rules, a fuzzy region-based multi-sensor image fusion approach is proposed in this paper. The similarity measure weight is adapted to this dynamic image fusion algorithm, while the tracking method uses the proposed multi-cue mean-shift tracking algorithm. Three experimental results using real world image sequences are evaluated using the steady state square root mean error. The fusion and tracking experiments indicate that the proposed approach is effective and efficient when aiming at a target moving from one area to a different area, which meets the robustness and real-time requirements. © 2012 Science China Press and Springer-Verlag Berlin Heidelberg.

Huang D.,Science and Technology on Avionics Integration Laboratory | Wang D.,Shanghai JiaoTong University | Wu S.,Shanghai JiaoTong University | Cai Y.,Shanghai JiaoTong University
Chinese Control Conference, CCC | Year: 2016

This paper firstly proposed a universal track initiation method with adaptive threshold. Using this method, performance under heavy clutter tracking environment is improved. Besides, joint probabilistic data association filter is the common data association method, which only deal with the fixed-numbered multi-target tracking problem. Introducing the data pre-association process, an improved JPDAF algorithm is proposed to accomplish variable-numbered multi-target tracking, which is validated by simulation results. © 2016 TCCT.

Wu J.,Science and Technology on Avionics Integration Laboratory | Mou Z.,Science and Technology on Avionics Integration Laboratory | Zhu Q.,Shanghai JiaoTong University | Li J.,Shanghai JiaoTong University | Zhou Y.,Xiangtan University
Optical Engineering | Year: 2012

Bearings-only tracking has been the focus of distinct research interest in the last few decades. To attack target maneuvering and measuring nonlinearity, most of the existing methods adopt an interactive multiple model (IMM) with a bank of nonlinear filtering recursions, such as an extended Kalman filter, an unscented Kalman filter (UKF), or a particle filter. However, these nine-state coupled-tracking methods usually suffer from low tracking accuracy due to inseparable model probability and high computational burden because of the calculating inverse of 9 × 9 matrices. This present work focuses on target tracking by two platforms's bearingsonly measurements in an axial decoupled way. First, the passive ranging formula is derived with the conversion error proven to be Gaussian noises. Then to reduce the computational burden and maintain high tracking accuracy, the diagonal least upper bound for the covariance matrix of conversion error is given. This makes the decoupled tracking algorithm applicable. To attack the target maneuvering, the present decoupled IMM that uses a bank of passive-ranging-based Kalman filters is adopted along each axis separately. Finally, the decoupled tracking algorithm is compared with conventional coupled IMM in Cartesian coordinates by criterions such as tracking accuracy, model probability, and computational burden. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE).

Luo D.,Science and Technology on Avionics Integration Laboratory | Luo D.,Xiamen University | Xu W.,Xiamen University | Wu S.,Xiamen University
Control and Intelligent Systems | Year: 2014

During formation flight for a group of unmanned aerial vehicles (UAVs), the UAV formation sometimes needs to be adjusted or transformed from one to another in cases of environmental change, task alternation as well as the drop of some UAVs in the group. For the adjustment and transformation of flight formation shape,collision between UAVs should be avoided and the formation switch process should be completed with in a given time. In this paper, proportional-integral- derivative (PID) control approach is used to design the controller for UAV formation holding first, then three formation transformation strategies are designed and a control method is adopted to ensure the transformation process can be accomplished within limited time. Simulation results demonstrate the effectiveness of the presented approach for UAV formation control and transformation.

Jiang X.,Harbin Institute of Technology | Jiang X.,Science and Technology on Avionics Integration Laboratory | Yao H.,Harbin Institute of Technology | Zhang S.,Harbin Institute of Technology | And 2 more authors.
2013 IEEE International Conference on Image Processing, ICIP 2013 - Proceedings | Year: 2013

Videos taken under low lighting condition usually have serious loss of visibility and contrast and are inconvenient for observation and analysis. To solve this problem, this paper presents a real-time night video enhancement approach. As observed that a pixel-wise inversion of a night video has quite similar appearance with the video acquired at foggy days, we use the similar idea of haze removal method to enhance the perceptual quality of the night videos. We present an improved dark channel prior model and integrate it with local smoothing and image Gaussian Pyramid operators. The experimental results demonstrate that the proposed approach can improve the perceptual quality of night videos in real-time in terms of not only enhancing details, but also effectively avoiding excessive enhancement phenomenon. © 2013 IEEE.

Xu Z.,Science and Technology on Avionics Integration Laboratory | Xu Z.,Yantai Naval Aeronautical and Astronautical University | Qu C.,Yantai Naval Aeronautical and Astronautical University | Wang C.,Yantai Naval Aeronautical and Astronautical University
Chinese Journal of Aeronautics | Year: 2013

In order to solve the bearings-only passive localization problem in the presence of erroneous observer position, a novel algorithm based on double side matrix-restricted total least squares (DSMRTLS) is proposed. First, the aforementioned passive localization problem is transferred to the DSMRTLS problem by deriving a multiplicative structure for both the observation matrix and the observation vector. Second, the corresponding optimization problem of the DSMRTLS problem without constraint is derived, which can be approximated as the generalized Rayleigh quotient minimization problem. Then, the localization solution which is globally optimal and asymptotically unbiased can be got by generalized eigenvalue decomposition. Simulation results verify the rationality of the approximation and the good performance of the proposed algorithm compared with several typical algorithms. © 2013 Production and hosting by Elsevier Ltd. on behalf of CSAA & BUAA.

Xu Z.,Science and Technology on Avionics Integration Laboratory | Xu Z.,Yantai Naval Aeronautical and Astronautical University | Qu C.,Yantai Naval Aeronautical and Astronautical University | Wang C.,Yantai Naval Aeronautical and Astronautical University
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2013

The presence of systematic errors may have great effect on the performance of passive localization of multiple observers. In this paper the Cramer-Rao lower bound (CRLB) is derived with respect to the measurements corrupted by systematic errors which are obtained by multiple moving observers. First, the statistical information of the measurement error is derived according to the specific systematic error model. Because of the dependence of measurements between different time instants caused by the systematic error, the error covariance matrix is non-diagonal. The recursive calculation form is then derived by rewriting the non-diagonal error covariance matrix into the form of block matrixes. Finally, simulation is performed with respect to multiple moving observers bearings-only passive localization and related localization performance analysis is made. Simulation results indicate that systematic errors can have great effect on the CRLB of location error and more attention should be paid to it.

Wang Q.,Science and Technology on Avionics Integration Laboratory | Ai J.-L.,Fudan University
Xitong Fangzhen Xuebao / Journal of System Simulation | Year: 2012

For the feature that a hypersonic vehicle has a large span of flight height and flight Mach number, and complicated flight environment, the model of which is highly nonlinear, unstable, multivariable coupled and includes uncertain aerodynamic parameters, dynamic surface control method is proposed to design its flight control system. The virtual signal and final control signal are designed by constructing dynamic surface variables and reachable conditions. The method does not involve differentials of some nonlinear signals by adding first order dynamic filters, and the calculation of control law is decreased greatly. The simulation on a generic hypersonic vehicle demonstrates that the proposed method can track the flight commands well. © Copyright.

Zheng F.,Science and Technology on Avionics Integration Laboratory | Qian Y.,Beijing University of Technology | Li H.,Beijing University of Technology
2015 IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC 2015 | Year: 2015

In this paper, the performance of interference sensing of full duplex cognitive anti-jamming (FCAJ) receiver impaired by phase noise in local oscillators is investigated under fading channel. Firstly, energy detection based the interference signal to noise ratio (INR) of FCAJ receiver with phase noise under different channels is analyzed. Then, the detection and false alarm probabilities in closed-form for FCAJ receiver are derived. Simulation results show that the degradation of the INR due to phase noise is more severe than that due to the channel. And the anti-jamming capability of wideband FCAJ receiver with phase noise outperforms the narrowband receiver at the same operation frequency bands. © 2015 IEEE.

Shi G.,Northwestern Polytechnical University | Zhang G.,Science and Technology on Avionics Integration Laboratory
ECTI-CON 2015 - 2015 12th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology | Year: 2015

In order to enhance the avionics' ground maintenance capabilities, a kind of signal acquisition and excitation system is designed. This paper describes the system overall design, hardware, software configuration and work flow, establishes the system hardware and software architecture, and designs the system's typical circuit, communication protocols, interrupt programs and USB drivers in detail. By using the USB bus as the computer communication bus, the Plug-and-Play (PNP) and Hot-plug problems are solved. Using computer control technology meets the demand on aviation system discrete signals control and detection. The cascade topology structure based on RS-485 bus is employed to solve the problems that the measured signal numbers are uncertainty. © 2015 IEEE.

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