• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.2
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• pp.75-82
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• 2002

It is useful to detect the tracking error with an optimal view in the presence of measurement origin uncertainty. In this paper, after the investigation of the targer error dependent on the detection threshold as well as the detection and false alarm probabilities in a clutter environment, a new algorothm that optimizes the threshold of validation region for target trackinf is proposed. The performance of the algorithm is demonstrated through computer simulations.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.1
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• pp.43-56
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• 1997

다중 표적 추적(MTT:Multiple Target Tracking)은 한 개 또는 그 이상의 센서들을 사용하는 감시(sureillance) 시스템을 위해서 컴퓨터와 마찬가지로 주변상황을 해석하는데 없어서는 안되는 중 요한 요소이다. 레이다, IR(Infrared) 및 Sonar등과 같은 전형적인 센서 시스템들은 여러 가지 신호원 (sources): 문제의 표적, 레이다 지면 클러터(clutter)같은 후면잡음 또는 열잡음같은 내부 오차 요인 으로부터 측정치(measurement)를 만들어 준다. 다중표적용 추적방식의 목적은 센서가 제공하는 측 정 데이터들을 동일한 신호원으로부터 나온 여러 세트의 관측치(observations) 또는 트랙(track)으로 구분해내는 것이다. 이와 같이 일단 트랙이 구성되고 확정되면 후면잡음이나 허위표적을 제거할 수 있 도록 표적의 수를 추산하고 표적의 속도나 예상위치 및 표적의 종류와 기타특성을 계산해낼 수 있다.

• Current Industrial and Technological Trends in Aerospace
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• v.4 no.1
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• pp.83-91
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• 2006

추적레이다는 표적으로부터 반사되어 돌아오는 신호 또는 질의 신호에 대한 응답 신호를 수신하여 표적을 추적하는 장비이다. 추적레이다가 표적을 추적하는 범위는 일반적으로 좁게 한정되므로 이동하는 표적을 추적하기 위해서는 먼저 안테나 빔의 지향각과 거리를 표적에 맞추고, 표적이 획득된 후에는 안테나 빔을 연속적으로 이동하는 표적을 향해 방사하여 표적을 추적하게 된다. 일반적으로 추적레이다가 표적을 추적하는 경우에는 과정 잡음과 측정 잡음에 의해서 발생되는 부정확성과 관심없는 표적이나 클러터 등으로부터 생성된 측정 근원의 부정확성으로 인한 문제가 발생하게 된다. 이러한 표적 추적에 따른 문제를 해결하기 위해서 많은 추적 알고리듬들이 개발되어 왔다. 이 논문에서는 가장 기본적인 표준 칼만 필터와 측정 근원의 부정확성에 따른 데이터 연관 문제를 고려한 여러 추적 알고리듬에 대해서 기술하였다. 또한 한국항공우주연구원 우주센터의 우주발사체 추적용 추적레이다에 대한 간략한 설명과 우주발사체 추적에 사용되는 추적 알고리듬에 대해서 소개하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.8
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• pp.1990-1997
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• 1998

It is very essential to remove a strong ground clutter and moving clutter for an extraction of accurate information from a Doppler weather radar. Therefore, this paper proposed the use of an adaptive array antenna to overcome the shortages of a conventional weather radar. In the first, a simulation method was suggested for the generation of clutter and weather signals. Using these data, the performance of a weather radar was analyzed under various conditions. It is shown that the quality of pulse-pair estimates was greatly improved from the simulation results.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.41 no.4
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• pp.13-20
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• 2004

In this paper, we developed a method for predicting the tracking performance of the multiple hypothesis tracking (MHT) algorithm. The MHT algerithm is known to be a measurement-oriented optimal Bayesian approach and is superior to any other tracking filters because it takes into account the events that the measurements can be originated from new targets and false alarms as well as interesting targets. In the MHT algorithm, a number of candidate hypotheses are generated and evaluated later as more data are received. The probability of each candidate hypotheses is approximately evaluated by using the hybrid conditional average approach (HYCA). We performed numerical experiments to show the validity of our performance prediction.

• The Journal of the Acoustical Society of Korea
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• v.39 no.6
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• pp.549-558
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• 2020

In this paper, the method is discussed such that the robustness of automatic initiated narrowband target tracking is improved in passive sonar. In the case of automatic tracking initiation as target in passive sonar, due to a number of clutter, the clutter is initiated as target and tracked which prohibits the operation capability. The associated probability and information entropy of measurements, extracted from detection data, is calculated to keep going on automatic target initiation and tracking of true target, but reduce the automatic initiation and tracking of clutter. If the association probability and information entropy of the extracted measurements is satisfied for the predefined conditions, the procedure of automatic initiation begins. Using sea-trial data, simulations are executed and the results from the proposed method indicate that it keeps the automatic target initiation and tracking of true target and suppresses the automatic target initiation and tracking of clutters in contrary to the conventional method.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.415-426
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• 2019

In this paper, we discussed automatic target tracking algorithms for diver detection sonar that observes penetration forces of coastal military installations and major infrastructures. First of all, we analyzed sea trial data in diver detection sonar and composed automatic target tracking algorithms based on track existence probability as track quality measure in clutter environment. In particular, these are presented track management algorithms which include track initiation, confirmation, termination, merging and target tracking algorithms which include single target tracking IPDAF (Integrated Probabilistic Data Association Filter) and multitarget tracking LMIPDAF (Linear Multi-target Integrated Probabilistic Data Association Filter). And we analyzed performances of automatic target tracking algorithms using sea trial data and monte carlo simulation data.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.7
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• pp.822-830
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• 2012

Clutters are all unwanted radar returns to affect on detection of targets. Radar clutter is characterized by amplitude distributions, spectrum, etc. Clutter is modelled with considering these kinds of characteristics. In this paper, a Weibull distribution function approximated by uniform distribution function is suggested. Weibull distribution function is used to model the various clutters. This paper shows that the data generated by the approximated solution of Weibull distribution function satisfy the Weibull probability density function. This paper shows that the data generation time of approximated Weibull distribution function solution is reduced by 20 % compared with the generation time of original Weibull probability density function.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.668-670
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• 2010

It is necessary to estimate the range and Doppler shifted spectrum for the extraction of useful information from the return echoes in the frequency modulated continuous wave radar systems used for the remote sending purpose such as detection of moving targets. However, the spectrum estimation using the FFT method causes the very large sidolobes of clutter masking the essential signal information if the acquisition time of an echo signal is pretty short. Therefore, in this paper, the efficient data windowing method is investigated to suppress the strong sidelobe levels of the clutter and results are analyzed.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.5
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• pp.333-340
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• 2003

Doppler processing is the heart of pulsed Doppler radar. It gives a clutter elimination and coherent integration. With the improvement of digital signal processors (DPSs), the implementation using them is more widely used in radar systems. Generally, so as for Doppler processor to process the input data in real time, a parallel processing concept using multiple DSPs should be used. This paper implements a programmable Doppler processor, which consists of MTI filter, DFB and square-law detector, using 8 ADSP21060s. Formulating the distribution time of the input data, the transfer time of the output data and the time required to compute each algorithm, it estimates total processing time and the number of required DSP. Finally, using the TSG that provides radar control pulses and simulated target signals, performances of the implemented Doppler processor are evaluated.