• 한국군사과학기술학회지
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• 제23권3호
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• pp.204-212
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• 2020

For general target tracking works by receiving a set of measurements from sensor. However, if the SNR(Signal to Noise Ratio) is low due to small RCS(Radar Cross Section), caused by remote small targets, the target's information can be lost during signal processing. TBD(Track Before Detect) is an algorithm that performs target tracking without threshold for detection. That is, all sensor data is sent to the tracking system, which prevents the loss of the target's information by thresholding the signal intensity. On the other hand, using all sensor data inevitably leads to computational problems that can severely limit the application. In this paper, we propose an iterative Joint Integrated Probabilistic Data Association as a practical target tracking technique suitable for a low SNR multi-target environment with real time operation capability, and verify its performance through simulation studies.

• Journal of Advanced Marine Engineering and Technology
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• 제38권10호
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• pp.1303-1309
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• 2014

In this paper, we present an iterative learning control (ILC) framework for tracking problems with predefined data points that are desired points at certain time instants. To design ILC systems for such problems, a new ILC scheme is proposed to produce output curves that pass close to the desired points. Unlike traditional ILC approaches, an algorithm will be developed in which the control signals are generated by solving an optimal ILC problem with respect to the desired sampling points. In another word, it is a direct approach for the multiple points tracking ILC control problem where we do not need to divide the tracking problem into two steps separately as trajectory planning and ILC controller.The strength of the proposed formulation is the methodology to obtain a control signal through learning law only considering the given data points and dynamic system, instead of following the direction of tracking a prior identified trajectory. The key advantage of the proposed approach is to significantly reduce the computational cost. Finally, simulation results will be introduced to confirm the effectiveness of proposed scheme.

• 항공우주기술
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• 제9권1호
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• pp.151-157
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• 2010

나로우주센터에서 운용하는 추적레이더는 위성발사체 (KSLV-1)의 비행궤도를 추적하여 위성발사체의 위치정보를 발사통제센터로 전송하는 추적시스템이다. 추적레이더가 획득한 위성발사체의 실시간 위치정보는 발사임무의 정상적인 수행 및 비행안전통제를 위해 중요한 자료이므로 위치정보의 정확도가 절실히 요구된다. 본 논문에서는 추적레이더가 획득한 측정값의 정확성을 판단하는 하나의 기준이 되는 잡음에 의한 오차 규격을 이론적으로 분석하고, 실제 획득한 측정값들이 이론적인 잡음에 의한 오차 규격을 만족하는 지 검증하였다. 이 분석에서 사용된 측정값들은 나로우주센터에서 수차례 수행하였던 모의비행시험에서 얻은 결과물을 이용하여 검증하였다.

• ETRI Journal
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• 제30권6호
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• pp.774-782
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• 2008

An operational orbit determination (OD) and prediction system for the geostationary Communication, Ocean, and Meteorological Satellite (COMS) mission requires accurate satellite positioning knowledge to accomplish image navigation registration on the ground. Ranging and tracking data from a single ground station is used for COMS OD in normal operation. However, the orbital longitude of the COMS is so close to that of satellite tracking sites that geometric singularity affects observability. A method to solve the azimuth bias of a single station in singularity is to periodically apply an estimated azimuth bias using the ranging and tracking data of two stations. Velocity increments of a wheel off-loading maneuver which is performed twice a day are fixed by planned values without considering maneuver efficiency during OD. Using only single-station data with the correction of the azimuth bias, OD can achieve three-sigma position accuracy on the order of 1.5 km root-sum-square.

• 로봇학회논문지
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• 제7권2호
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• pp.113-119
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• 2012

In this paper we propose the method that detects moving objects in autonomous navigation vehicle using LRF sensor data. Object detection and tracking methods are widely used in research area like safe-driving, safe-navigation of the autonomous vehicle. The proposed method consists of three steps: data segmentation, mobility classification and object tracking. In order to make the raw LRF sensor data to be useful, Occupancy grid is generated and the raw data is segmented according to its appearance. For classifying whether the object is moving or static, trajectory patterns are analysed. As the last step, Markov chain Monte Carlo (MCMC) method is used for tracking the object. Experimental results indicate that the proposed method can accurately detect moving objects.

• 한국콘텐츠학회논문지
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• 제7권8호
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• pp.94-101
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• 2007

본 논문에서는 휴대폰을 위한 무선 인터넷 플랫폼의 표준인 WIPI를 이용한 모바일 시스템과 사람추적 시스템을 결합한 모바일 플랫폼 기반의 사람추적 감시시스템을 제안한다. 제안된 시스템은 크게 사람추적 시스템과 모바일 정보교환 시스템으로 구분된다. 사람추적 시스템에서는 감시지역에 침입한 사람들을 추적하고, 모바일 정보교환 시스템은 사람추적 시스템에서 추적된 결과를 사용자의 모바일 폰으로 전송한다. 본 논문에서 사용하는 사람추적 시스템은 넓은 시야 확보를 위해 카메라의 시야를 겹치지 않게 배치한 상태에서 사람들을 추적한다. 모바일 정보교환 시스템은 추적된 결과를 서버에 자동적으로 저장하여 사용자의 WIPI 모바일 폰으로 저장된 정보를 전달하게 된다. 따라서 추후에 사용자가 감시상황을 재확인하고자 했을 시, 카메라 별 또는 시간 별로 선택하여 영상을 재확인 할 수 있다. 제안된 시스템은 추적 영역과 감시 영역의 공간적 제약과 감시 시간의 시간적 제약을 해결하기 위해 카메라들과 모바일 폰 사이의 추적결과를 교환할 수 있는 새로운 형태의 감시시스템이다.

• 대한임베디드공학회논문지
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• 제6권1호
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• pp.16-24
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• 2011

Automotive Radar Systems are currently under development for various applications to increase accuracy and reliability. The target tracking is most important in single or multiple target environments for accuracy. The tracking algorithm provides smoothed and predicted data for target position and velocity(Doppler). To this end, the fixed gain filter(${\alpha}{\beta}$ filter, ${\alpha}{\beta}{\gamma}$ filter) and dynamic filter(Kalman filter, Singer-Kalman filter, etc) are commonly used. Gating is used to decide whether an observation is assigned to an existing track or new track. Gating algorithms are normally based on computing a statistical error distance between an observation and prediction. The data association takes the observation-to-track pairings that satisfied gating and determines which observation-to-track assignment will actually be made. For data association, NNPDA(Nearest Neighbor Probabilistic Data Association) algorithm is proposed. In this paper, we designed a target tracking system developed for an Automotive Radar System. We show the experimental results of the 77GHz FMCW radar sensor on the roads. Four tracking algorithms(${\alpha}{\beta}$ filter, ${\alpha}{\beta}{\gamma}$ filter, 2nd order Kalman filter, Singer-Kalman filter) have been compared and analyzed to evaluate the performance in test scenario.

• 한국수산과학회지
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• 제54권5호
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• pp.787-797
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• 2021

Yellowtail Seriola quinqueradiata tagged with a Pop-up Satellite Archival Tag (PSAT) was released off the coast of near the Moseulpo, Jeju Island and the ecological data during about 40 days was obtained. However, it is difficult to determine the spatial location of underwater ecological data. To improve the accuracy of estimating the Yellowtail migration route using temperature, suitable background field of the oceanic environment data was evaluated and used for input data. After developing of the tracking algorithm for migration route estimation, three experiment cases were estimated with ecological data among the surface layer, the mixed layer, and the whole water column. All tracking experiments move from western to eastern Jeju Island. Additionally, tracking experiment using 3D ocean numerical model reveal that it is possible to estimate the migration route using the fish ecological data of the entire water column. Therefore, using a large number of ecological data and a high-accuracy ocean numerical model to estimate the migration route seems to be a way to increase the accuracy of the tracking experiment. Moreover, the tracking algorithm of this study can be applied to small pelagic fishery using small archival electronic tags to track the migration route.

• 전기학회논문지
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• 제61권5호
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• pp.726-734
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• 2012

In this paper, a practical warhead tracking filter is proposed for developing a FMCW (Frequency Modulation Continuous Wave) seeker with anti-ballistic missile capability. For reliable warhead tracking, the measurement originated from the warhead section of a ballistic target should be separated from other measurements. Futhermore, since the FMCW seeker is based on triangular frequency modulation, the multiple measurements obtained in different chirp periods should be properly associated. As a systematic way to solve the problem, the measurement pairing problem under cluttered environment is reformulated as a data association filtering problem and the PDA (Probabilistic Data Association) scheme is applied. The proposed warhead tracking filter provides better warhead tracking performance compared to the conventional range tracking algorithm and nearest neighbor warhead tracking filter. The effectiveness and reliability of the proposed method are verified using the FMCW seeker simulator.

• 항공우주기술
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• 제10권2호
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• pp.170-176
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• 2011

본 논문에서는 지상국에서 추적한 저궤도 위성의 방위각 및 고도각을 관측자료로 이용하여 궤도결정을 수행한 결과를 분석하였다. 지상국 추적 데이터는 발사 후 초기 궤도결정을 위한 관측자료로 유용하게 사용된다. 이를 위해 지상국 추적데이터에 대한 표준 인터페이스 포맷을 정리하였고, 특정 지상국에 대한 추적 데이터의 통계적인 특성을 살펴보았다. 최소자승법을 이용한 궤도결정을 위해 연속되는 교신패스를 통해 얻은 아리랑 2호의 방위 각/고도각을 축적하여 관측자료로 이용함으로써 다양한 조합에 따른 궤도결정 결과를 분석하였고, 궤도결정 성능 검증을 위해 GPS 항행해를 이용한 궤도결정 값과 비교하였다.