• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10b
• /
• pp.468-473
• /
• 1993

Augmented proportional navigation requires the information of a target acceleration, which must be estimated by a filtering logic. The process necessary accompanies a time lag, which degrades the guidance performance. A trade-off study between augmented and conventional proportional navigation is conducted with the time lag taken into consideration. The result shows that the conventional proportional navigation has better performance against a target maneuver in the missile-target coplane, while the augmented has better performance against out-of-coplane maneuver.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.7
• /
• pp.1550-1558
• /
• 1997

In this paper, we first propose a modified OS CFAR detector called the order statistics cell averaging(OSCA) CFAR detector and anlyze its performance for a Rayleigh target in homogeneous backgrounds, clutter edges, and satistics smallest of(OSSO) CFAR detectors for a Rayleigh target to nonhomogeneous environments. Computer simulation results show that the OSCA CFAR detector has superior performance to OS, OSGO, and OSSO CFAR detectors in homogeneous and multiple target environments. And the proposed detector shows its robustness for fast detection because it requires falf the processing time of the OS CFAR detector.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.426-429
• /
• 1997

This paper proposes a robust H$_{\infty}$ tracking filter to improve the unacceptable target tracking performance for systems with parameter uncertainties. Also, we use here the input estimation approach to account for the possibility of maneuver. Simulation results show that the robust H$_{\infty}$ tracking filter which is proposed here to solve the systems with all system parameter uncertainties, has a good tracking performance for a maneuvering target tracking problem.m.

• IE interfaces
• /
• v.23 no.3
• /
• pp.239-245
• /
• 2010

This paper considers a localization problem of a moving tag on RFID(Radio Frequency Identification) systems, where a positioning engine collects TDOA(Time-difference of Arrival) signal from a target tag to estimate the position of the tag. To localize the tag in the RFID system, we develop two heuristic algorithms and evaluate their performance in the estimation error and computational time by using randomly generated numerical examples. Based upon the performance evaluation, we can conclude our algorithms are valuable for localization the moving target.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10a
• /
• pp.218-223
• /
• 1993

In this paper, we modify a multiple target angle tracking algorithm presented by Sword et al.. The predicted estimates, instead of the existing estimates, of the target angles are updated by the most recent output of the sensor array to improve the tracking performance of the algorithm for crossing targets. Also, the least square solution is modified to avoid abnormally large angle innovations when the target angles are very close. The improved performance of the proposed algorithm is demonstrated by computer simulations.

• Journal of the Korea Society for Simulation
• /
• v.9 no.4
• /
• pp.77-85
• /
• 2000

The object of this paper is developing of a simulation model for performance evaluation of ai defense-gun system. We developed a three-step kill probability of areal target in case of one gun on one target considering : 1) estimating the target and warhead intercept point, 2) target vulnerability and 3) computing the kill probability. We used a Monte Carlo simulation method. This model can be used for probabilistic analysis giving results of sufficient accuracy with minimum requirement of input data. Also we developed a computer program according proposed algorithm and a set of experimental results using the proposed method are shown.

• Proceedings of the KIEE Conference
• /
• 2001.11c
• /
• pp.26-29
• /
• 2001

In a target tracking problem the radar glint noise has non-Gaussian heavy-tailed distribution and will seriously affect the target tracking performance. In most nonlinear situations an Extended Robust Kalman Filter(ERKF) can yield acceptable performance as long as the noises are white Gaussian. However, an Extended Robust $H_{\infty}$ Filter (ERHF) can yield acceptable performance when the noises are Laplacian. In this paper, we use the Interacting Multiple Model(IMM) estimator for the problem of target tracking with glint noise. In the IMM method, two filters(ERKF and ERHF) are used in parallel to estimate the state. Computer simulations of a real target tracking shows that hybrid filter used the IMM algorithm has superior performance than a single type filter.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.39 no.2
• /
• pp.192-198
• /
• 1990

The performance of the proportional navigation guidance(PNG) law for a target with constant acceleration has been extensively studied in the prior literature. In this papaer, we consider the performance of the PNG law for a randomly maneuvering target. By means of Lyapunov method, we prove that an ideal missile guided by the conventional PNG law can always intercept a randomly maneuvering target if the initial missile heading error is small and the navigation constant is chosen sufficiently large. To the authors' best knowledge, this is the first analytic result on the performance of the PNG law for a target with time-varying acceleration.

• Journal of the Semiconductor & Display Technology
• /
• v.9 no.2
• /
• pp.111-116
• /
• 2010

In a large area magnetron sputtering system, which is under the influence of high heat load from the plasma, it is necessary to use the effective water cooling in order to maintain the proper deposition performance and the economic use of target materials. A series of three-dimensional numerical simulations are carried out on the simplified model of the large area magnetron sputtering system with the cooling plate that includes the U-shaped water channel. The analysis is focused on the effects of water channel geometry, cooling water flowrate, thermal conductivity of target material, and the degree of target erosion on the cooling performance of cooling plate, which is represented by the temperature distribution of target material.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.10 no.4
• /
• pp.71-78
• /
• 2014

Method a target estimation in spatial are mobile wireless communication using network cell and GPS. It have much error that mobile wireless communication depend on cell size. GPS method can't find a target in shadow and inner area. In this paper, we estimate a target as direction of arrival method using adaptive array antenna system. Adaptive array antenna system can obtain desired signal to remove other signal This paper studied digital beamforming method in order to estimation a target. Proposed method is modified optimum weight and antenna error correction to estimation an optimal receive signal. Digital beamforming method decided a signal phase and amplitude from received signal on array antenna element. But if it is not to do error correction of received signal, system performance have decreased. Firstly, we proposed modified optimum weight in order to finding desired target. Secondly, we are error correction of antenna incident signals by optimal weight before digital beamforming method. Thirdly, throughly simulation, we showed that system performance of proposed method compare proposal method with general method. It have improved resolution of estimation target to good performance more proposed method than general method.