• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.478-479
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• 2008

본 연구에서는 비접촉 방식으로 심박과 호흡을 측정하기 위해 2.4GHz 대역에서 동작하는 도플러 레이더 센서와 베이스밴드 모듈로 구성된 도플러 레이더 시스템을 설계하고 그 성능을 평가하였다. 설계된 도플러 레이더 시스템은 심폐활동에 의한 흉부 표면의 움직임에 의해 반사되는 레이더의 위상변화를 이용하여 심폐 활동을 측정한다. 도플러 레이더 센서의 출력은 베이스 밴드 모듈의 전처리 필터부, 증폭부, 오프셋 조정부를 통과하여 호흡과 심박 신호로 분리된다. 분리된 생체신호는 기존의 생체신호와 상관성을 확인하기 위해 기준신호로 호흡과 심전도를 동시에 측정하여 그 결과를 비교 및 분석하였다. 설계된 도플러 레이더 시스템에서 분리된 호흡 및 심박 신호는 측정 대상의 움직임이 없는 상태에서는 높은 검출률을 보였으며, 도플러 레이더에서 심박과 호흡 신호를 검출한 결과 거리, 호흡과 심박의 변이량, 호흡과 심박대역에 따라 검출률이 영향을 받는다는 것을 알 수 있었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.623-628
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• 2015

The paper produced an application that used Doppler radar sensor to prevent bicycle related accidents. Doppler radar sensor detects any approaching object and gives warning to the user through the danger detection algorithm of the application. The danger detection algorithm determines danger by comparing relative speed using the sensed approaching object and Doppler frequency. It also sends SMS to the preset contact to let him/her be informed of the critical situation in which the user lies when an accident happens. The experiment result showed that the algorithm judged danger by detecting the approach status and speed as well as sent out SMS to the set contact under the assumption that there was an accident.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.5
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• pp.931-936
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• 2018

We designed an x-band radar for motion detector using a frequency tunable hairpin ring resonator. The proposed doppler radar sensor can vary the oscillation frequency by applying a hairpin resonator using a varactor diode to the oscillator, and this can also reduce the size by transmitting and receiving a signal from Tx/Rx dual antenna. The fabricated doppler radar sensor was fabricated in $30{\times}24mm$, and it was confirmed that the pulse width difference occurred according to the distance from the object. The measurement results showed oscillation at 10.525GHz. We confirmed that it is enough to use as radar for motion detection from the measured results.

• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.2
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• pp.75-81
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• 2009

In this paper, Microwave doppler radar sensor operated in 10.525GHz is designed by dielectric resonant oscillator. According to doppler effects, a characteristic of Microwave sensor with FMCW was analyzed. The qualities of objects velocity and distance between object and microwave sensor by sensor output frequency difference was measured. As a result of Microwave doppler radar sensor, the prototype sensor is available for indoor burglar alarms and other application through FMCW signal.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.133-136
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• 2008

본 논문에서는 도플러 레이더 센서를 이용하여 전자식 안정기의 조광 제어 기법을 제시하였다. 현재 대형 건물, 터널 및 도로에 설치되어 있는 수많은 안정기들은 조광 제어 없이 항상 정출력을 내고 있어 상당한 에너지 낭비를 초래하고 있다. 또한 장시간 동안 정출력 점등에 의해 램프의 수명을 단축시키는 원인이 되고 있다. 이를 해결하고자 도플러 레이더 센서를 이용한 조광 제어 시스템을 구현하였으며, prototype 400W MHD 램프용 전자식 안정기에 적용한 실험을 통하여 조광 제어 기법의 유용함을 증명하였다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.1
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• pp.1-9
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• 2009

In this paper, a 2.4 GHz doppler radar system consisting of a doppler radar sensor and a baseband module were designed to detect heart beat and respiration signal without direct skin contact. The doppler radar system emits RF signal of 2.4 GHz toward human chest, and then detects phase modulation of the reflected signal so as to investigate cardiopulmonary activities. The heartbeat and respiration signals acquired from I/Q channels of the doppler radar system are applied to the pre-processing circuit, the amplification circuit, and the offset circuit of the baseband module. The designed system was tested on mouse, rabbit and mankind, which have different range of heart rates and respiration signals, to evaluate detection accuracy of the system. ECG acquisition system and respiration transducer were used to generate the reference signal. In our experiments, a performance of detection were found to be high in the case that the subject stays still. In this paper, we confirmed that non-contact heart beat and respiration detection using the doppler radar has the possibility and limitation according to distance, cardiopulmonary activities, range of heart rates and respiration.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.2
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• pp.75-82
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• 2001

In this paper, a transmitter and a receiver using a Gunn diode and SBD was designed and fabricated in X-band. This system detects Doppler shift signal reflected by moving target through the homodyne detection, which is Doppler radar sensor for the measurement of the velocity of moving target. By the experimental results, the oscillating condition of the transmitter was satisfied at about the half wavelength between the supporting post of the Gunn diode in the waveguide and the waveguide short. And using the fabricated Doppler radar sensor, the velocity measurement deviation of moving target was 1.24%.

• Electronics and Telecommunications Trends
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• v.22 no.5
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• pp.35-45
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• 2007

전방감지용 밀리미터파 레이더는 밀리미터파를 이용하여 자동차 등에 부착하여 송신파와 수신파 사이의 도플러 주파수 편이를 이용하여 선행차량 또는 전방의 장애물과의 거리와 상대속도를 판별하는 장치로서 적응형 순항제어 시스템(adaptive cruise control system) 등에 이용되는 핵심 기술이다. 적응형 순항제어 시스템이란 레이더 센서를 통하여 전방 선행 차량, 장애물의 속도 및 거리를 측정하여 차량의 충돌 경고, 주행 상황에 따른 자동적인 감속 및 가속, 정속 등 안전주행을 가능하도록 하는 기술이다. 본 기술 동향 분석보고서는 전방감지용 레이더 센서에 관한 기술 동향을 살펴보기 위하여 미국, EU, 일본, 한국의 전방감지용 레이더 센서에 관한 특허를 1991년부터 2005년까지의 특허출원을 중심으로 연도별 추이와 국가별 특허출원 동향, 출원인별 특허출원 동향 등을 분석하여 전방감지용 레이더의 세계 기술 추이에 대하여 알아보았다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.552-554
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• 2021

We propose a fall recognition system using a deep learning algorithm using motion data acquired by a Doppler radar sensor. Among the deep learning algorithms, an RNN that has an advantage in time series data is used to recognize falls. The fall data of the Doppler radar sensor has a temporal characteristic as time series data, and the structure of the RNN is sequenced because the result only determines whether a fall or not It is designed in a structure that outputs a fixed size to the input.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.5
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• pp.218-232
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• 2022

Researches are underway to use a radar sensor, a sensor used for object recognition in vehicles, for position estimation. In particular, a method of classifying dynamic and static objects using the Doppler velocity, the output from the radar sensor, and calculating ego-motion using only static objects has been researched recently. Also, for the existing dynamic object classification, several methods using RANSAC or robust filtering has been proposed. Still, a classification method with higher performance is needed due to the nature of the position estimation, in which even a single failure causes large effects. Hence, in this paper, we propose a method to improve the classification performance compared to existing methods through tracking and filtering of dynamic objects. Additionally, the method used a GMPHD filter to maximize tracking performance. In effect, the method showed higher performance in terms of classification accuracy compared to existing methods, and especially shows that the failure of the RANSAC could be prevented.