• Title/Summary/Keyword: 표적 이동

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Classification of Doppler Audio Signals for Moving Target Using Hidden Markov Model in Pulse Doppler Radar (펄스 도플러 레이더에서 HMM을 이용한 이동표적의 도플러 오디오 신호 식별)

  • Sim, Jae-Hun;Lee, Jung-Ho;Bae, Keun-Sung
    • Journal of IKEEE
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    • v.22 no.3
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    • pp.624-629
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    • 2018
  • Classification of moving targets in Pulse Doppler Radar(PDR) for surveillance and reconnaissance purposes is generally carried out based on listening and training experience of Doppler audio signals by radar operator. In this paper, we proposed the automatic classification method to identify the class of moving target with Doppler audio signals using the Mel Frequency Cepstral Coefficients(MFCC) and the Hidden Markov Model(HMM) algorithm which are widely used in speech recognition and the classification performance was analyzed and verified by simulations.

Depth estimation of an underwater target using DIFAR sonobuoy (다이파 소노부이를 활용한 수중표적 심도 추정)

  • Lee, Young gu
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.3
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    • pp.302-307
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    • 2019
  • In modern Anti-Submarine Warfare, there are various ways to locate a submarine in a two-dimensional space. For more effective tracking and attack against a submarine the depth of the target is a critical factor. However, it has been difficult to find out the depth of a submarine until now. In this paper a possible solution to the depth estimation of submarines is proposed utilizing DIFAR (Directional Frequency Analysis and Recording) sonobuoy information such as contact bearings at or prior to CPA (Closest Point of Approach) and the target's Doppler signals. The relative depth of the target is determined by applying the Pythagorean theorem to the slant range and horizontal range between the target and the hydrophone of a DIFAR sonobuoy. The slant range is calculated using the Doppler shift and the target's velocity. the horizontal range can be obtained by applying a simple trigonometric function for two consecutive contact bearings and the travel distance of the target. The simulation results show that the algorithm is subject to an elevation angle, which is determined by the relative depth and horizontal distance between the sonobuoy and target, and that a precise measurement of the Doppler shift is crucial.

Tracking Algorithm Based on Moving Slide Window for Manuevering Target (이동표적을 위한 이동 창 함수 기반 추적 알고리즘)

  • Bae, Jinho;Lee, Chong Hyun;Jeon, Hyoung-Goo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.4
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    • pp.129-135
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    • 2016
  • In this paper, we propose a novel tracking algorithm called slide window tracker (SWT) suitable for maneuvering target. To efficiently estimate trajectory of moving target, we adopt a sliding piecewise linear window which includes past trace information. By adjusting the window parameters, the proposed algorithm is to reduce measurement noise and to track fast maneuvering target with little computational increment as compared to ${\alpha}-{\beta}$ tracker. Throughout the computer simulations, we verify outstanding tracking performance of the SWT algorithm in noisy linear and nonlinear trajectories. Also, we show that the SWT algorithm is not sensitive to initial model parameter selection, which gives large degree of freedom in applying the SWT algorithm to unknown time-varying measurement environments.

Underwater Target Localization Using the Interference Pattern of Broadband Spectrogram Estimated by Three Sensors (3개 센서의 광대역 신호 스펙트로그램에 나타나는 간섭패턴을 이용한 수중 표적의 위치 추정)

  • Kim, Se-Young;Chun, Seung-Yong;Kim, Ki-Man
    • The Journal of the Acoustical Society of Korea
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    • v.26 no.4
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    • pp.173-181
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    • 2007
  • In this paper, we propose a moving target localization algorithm using acoustic spectrograms. A time-versus-frequency spectrogram provide a information of trajectory of the moving target in underwater. For a source at sufficiently long range from a receiver, broadband striation patterns seen in spectrogram represents the mutual interference between modes which reflected by surface and bottom. The slope of the maximum intensity striation is influenced by waveguide invariant parameter ${\beta}$ and distance between target and sensor. When more than two sensors are applied to measure the moving ship-radited noise, the slope and frequency of the maximum intensity striation are depend on distance between target and receiver. We assumed two sensors to fixed point then form a circle of apollonios which set of all points whose distances from two fixed points are in a constant ratio. In case of three sensors are applied, two circle form an intersection point so coordinates of this point can be estimated as a position of target. To evaluates a performance of the proposed localization algorithm, simulation is performed using acoustic propagation program.

A Virtual Array Design of 77 GHz Vehicle Radar for Detecting Moving Targets (이동표적 탐지를 위한 77 GHz 차량레이더용 가상배열 설계)

  • Kim, Doo-Soo;Hong, Dong-Hee;Joo, Jeong-Myeong;Yang, Jin-Mo;Lee, Sang-In
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.5
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    • pp.435-444
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    • 2015
  • This paper specifies on a virtual array design of a 77 GHz vehicle radar for detecting a moving target at a time division transmit and a near range. The virtual array designed reduces a hardware complexity, weight and price. However, a synthesized beam of the virtual array has a high side lobe by a phase distortion of receive signals when the moving target is detected at the time division transmit. For this, a subarray receive signal with a same phase is used and the side lobe of the synthesized beam is suppressed above at least 10 dB. Also the virtual array has a beam distortion by a spherical wave when the vehicle radar operates at near range. So a boresight receive signal of each target range is compensated at each receive signal. Therefore the synthesized beam with compensation recovers a normal main lobe and improves the side lobe about 10~15 dB.

Stereo Object Tracking System using Multiview Image Reconstruction Scheme (다시점 영상복원 기법을 이용한 스테레오 물체추적 시스템)

  • Ko, Jung-Hwan;Ohm, Woo-Young
    • 전자공학회논문지 IE
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    • v.43 no.2
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    • pp.54-62
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    • 2006
  • In this paper, a new stereo object tracking system using the disparity motion vector is proposed. In the proposed method, the time-sequential disparity motion vector can be estimated from the disparity vectors which are extracted from the sequence of the stereo input image pair and then using these disparity motion vectors, the area where the target object is located and its location coordinate are detected from the input stereo image. Basing on this location data of the target object, the pan/tilt embedded in the stereo camera system can be controlled and as a result, stereo tracking of the target object can be possible. From some experiments with the 2 frames of the stereo image pairs having $256\times256$ pixels, it is shown that the proposed stereo tracking system can adaptively track the target object with a low error ratio of about 3.05 % on average between the detected and actual location coordinates of the target object.

Stereo Object Tracking and Multiview image Reconstruction System Using Disparity Motion Vector (시차 움직임 벡터에 기반한 스데레오 물체추적 및 다시점 영상복원 시스템)

  • Ko Jung-Hwan;Kim Eun-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.2C
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    • pp.166-174
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    • 2006
  • In this paper, a new stereo object tracking system using the disparity motion vector is proposed. In the proposed method, the time-sequential disparity motion vector can be estimated from the disparity vectors which are extracted from the sequence of the stereo input image pair and then using these disparity motion vectors, the area where the target object is located and its location coordinate are detected from the input stereo image. Being based on this location data of the target object, the pan/tilt embedded in the stereo camera system can be controlled and as a result, stereo tracking of the target object can be possible. From some experiments with the 2 frames of the stereo image pairs having 256$\times$256 pixels, it is shown that the proposed stereo tracking system can adaptively track the target object with a low error ratio of about 3.05$\%$ on average between the detected and actual location coordinates of the target object.

Wide-band Matched Field Processing Against Source Motion : STMV (표적의 이동에 의한 영향을 극복하기 위한 광대역 정합장처리)

  • Park J.S.;Kim J.S.;Kim S.I.;Kim Y.G.
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.389-392
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    • 2004
  • 정합장처리를 이용한 표적의 탐지는 다양한 종류의 간섭표적들이 존재하는 환경에서 수행될 가능성이 크며, 따라서 분해능이 높은 적응 정합장처리를 사용이 요구된다. 반면 빠르게 움직이는 고소음의 간섭표적이 존재 할 경우에는 적응정합장처리를 수행하기위한 신호단편 (snapshot) 수를 충분하게 사용할 수 없는 상황에 직면하게 된다. 제한된 신호단편을 이용하여 적응정합장처리의 CSDM (cross-spectral density matrix)을 안정적으로 추정하기 위한 목적으로 선형빔형성에서 제안되었던 광대역 STMV (steered minimum varianve) 기법을 도입하였다. MAPLE03 실험환경을 이용하여 STMV의 적응정합장처리 수치실험을 수행하고 특성을 분석하였다.

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Coherent Multiple Target Angle-Tracking Algorithm (코히어런트 다중 표적 방위 추적 알고리즘)

  • Kim Jin-Seok;Kim Hyun-Sik;Park Myung-Ho;Nam Ki-Gon;Hwang Soo-Bok
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.4
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    • pp.230-237
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    • 2005
  • The angle-tracking of maneuvering targets is required to the state estimation and classification of targets in underwater acoustic systems. The Problem of angle-tracking multiple closed and crossing targets has been studied by various authors. Sword et al. Proposed a multiple target an91e-tracking algorithm using angular innovations of the targets during a sampling Period are estimated in the least square sense using the most recent estimate of the sensor output covariance matrix. This algorithm has attractive features of simple structure and avoidance of data association problem. Ryu et al. recently Proposed an effective multiple target angle-tracking algorithm which can obtain the angular innovations of the targets from a signal subspace instead of the sensor output covariance matrix. Hwang et al. improved the computational performance of a multiple target angle-tracking algorithm based on the fact that the steering vector and the noise subspace are orthogonal. These algorithms. however. are ineffective when a subset of the incident sources are coherent. In this Paper, we proposed a new multiple target angle-tracking algorithm for coherent and incoherent sources. The proposed algorithm uses the relationship between source steering vectors and the signal eigenvectors which are multiplied noise covariance matrix. The computer simulation results demonstrate the improved Performance of the Proposed algorithm.

Real-time Small Target Detection using Local Contrast Difference Measure at Predictive Candidate Region (예측 후보 영역에서의 지역적 대비 차 계산 방법을 활용한 실시간 소형 표적 검출)

  • Ban, Jong-Hee;Wang, Ji-Hyeun;Lee, Donghwa;Yoo, Joon-Hyuk;Yoo, Seong-eun
    • Journal of Korea Society of Industrial Information Systems
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    • v.22 no.2
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    • pp.1-13
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    • 2017
  • In This Paper, we find the Target Candidate Region and the Location of the Candidate Region by Performing the Morphological Difference Calculation and Pixel Labeling for Robust Small Target Detection in Infrared Image with low SNR. Conventional Target Detection Methods based on Morphology Algorithms are low in Detection Accuracy due to their Vulnerability to Clutter in Infrared Images. To Address the Problem, Target Signal Enhancement and Background Clutter Suppression are Achieved Simultaneously by Combining Moravec Algorithm and LCM (Local Contrast Measure) Algorithm to Classify the Target and Noise in the Candidate Region. In Addition, the Proposed Algorithm can Efficiently Detect Multiple Targets by Solving the Problem of Limited Detection of a Single Target in the Target Detection method using the Morphology Operation and the Gaussian Distance Function Which were Developed for Real time Target Detection.