• 한국산학기술학회논문지
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• 제15권5호
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• pp.3114-3120
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• 2014

산업현장에서 사용되는 무선 비상호출 스위치의 성공적인 운영을 위해서는 지속적인 전원의 공급이 이루어져야 한다. 본 논문은 배터리가 필요 없는 무선 스위치에 적용할 수 있는 전자기 유도방식의 초소형 에너지 하베스팅 메커니즘 개발 및 구현된 메커니즘의 성능 실험 결과를 보여주고 있다. 연구결과로 단 방향 누름 동작과 2mm 이동거리의 제한조건 내에서, 유도기전력을 생성하는 새로운 메커니즘이 제시됐다. 또한, 구현된 메커니즘의 전자기 유도 발전 출력 성능 실험결과로 VDC $4.5V{\pm}25%$(도달시간 1.2msec), 2.5V 이상 전압의 발전시간이 65ms가 됨을 보여주고 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.3256-3258
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• 1999

Recently contactless ID system has emerged as new ID industry. It's called RF-ID. RF-ID is divided into active RF-ID and passive RF-ID. The passive RF-ID operates without battery and so has no limitation in its operating range and life time. But it needs the RF-OC conversion circuit. It also can be applied to batteryless sensor for many application. This paper presents the study of the RF-OC conversion circuit for batteryless system in high frequency and confirms it by simulation and experiment.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.318-321
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• 2003

In case, sensor system performs where it is difficult to access physically and it is in the poor environment, it is limited to communicate by using wire and installing power module in sensor system. In this paper, it suggests how information is obtained from telemetry sensor by means of inductive coupling without battery. Comparing with the telemetry sensor system of inductive coupling by the power supply, this system estimates the capacitance of sensor with high precision in using RLSE, not the process of modulation and demodulation. In order to activate this system, inductive model is used and in case of time variant parameter, telemetry sensor system which has got high rate in accuracy is implemented by using the forgetting factor.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.1001-1004
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• 2000

RFID system is applied to identify, locate and track people, cars, animals. In RFID system, the passive transponder without battery has some benefits than active transponder, such as no restriction in battery exchange and in battery’s life. But it needs auxiliary RF-DC conversion circuit. RF-DC conversion circuit originated from Wireless Power Transmission (WPT). In this paper, RF-DC conversion circuit consists of a microstrip patch antenna and impedance matching circuit, Cock-croft Walton circuit. And RF-DC conversion circuits have two kinds of T-type and Cross-type impedance matching circuits.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.66-67
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• 2017

본 논문은 Solar Cell을 응용하여 통신기능과 함께 전원공급이 가능한 배터리 없는 가시광 통신용 수신기를 제안한다. 기존 포토다이오드(PD : Photo Diode)를 적용한 가시광 통신용 수신기는 수신신호 처리를 위한 PD 드라이버와 신호 처리부를 동작시키기 위하여 별도의 전원 회로와 배터리가 필요하다. 따라서, 체적 및 비용의 증가가 불가피하여 가시광 통신의 큰 문제점으로 대두되고 있다. 하지만 제안회로는 PD를 Solar Cell로 대체하여 기존의 신호를 수신함과 동시에 Solar Cell의 광전효과를 통해 생성된 전력을 사용하여 별도의 부가회로 없이 전원 공급이 가능하며 무선통신 기술의 새로운 패러다임을 제시한다. 제안된 회로의 타당성 검증을 위해 Solar Cell을 응용한 시작품을 제작하여 실험 결과를 제시한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2017-2019
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• 2003

열악한 환경에서 동작해야 하거나 물리적 접근이 어려운 곳에 장착되는 센서 시스템의 경우, 유선에 의한 정보전달이 어려울 뿐만 아니라 센서 내 전원설비가 제한적인 수도 있다. 따라서 본 논문에서는 이러한 문제점에 대한 해결책으로서 밧데리없이 유도결합에 의하여 원격 센서로부터 정보 취득이 가능한 한 방법을 제안하였다. 이 방법은 전원공급에 의한 유도 결합식의 원격 센서 시스템과는 달리, 원격 센서의 정전용량을 변 복조 과정 없이 재귀적 최소 자승 추정법에 의해 센서의 정전용량을 고정도로 추정하는 것이다. 이를 위하여 시 스템의 유도결합 모델을 사용하였으며, 모델 파라미터가 시간에 따라 변화하는 경우에는 망각률을 사용하여 정확도가 높은 원격 센서 시스템을 구현할 수 있었다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 공동학술대회
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• pp.496-497
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• 2009

This paper describes about the realization of a remote RF sensor system and its applications. RF Sensor System was designed and realized on DSP over the range of high frequency such as about 200[KHz]. It should be "wireless", "implantable" and "batteryless". Futhermore, the system should be consist of passive components such as R, Land C. The measurement was given using the inductive coupling principle between primary source part and secondary sensor part. This newly developed parameter estimation system can be easily applied to the Ambient Intelligent System including the ubiquitous computing and the sensitive environmental changes.

• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.416-421
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• 2011

Nowadays, the increasing demands upon mobile devices such as wireless sensor networks and the recent advent of low power electrical devices such as MEMS make such renewable power sources attractive. A vibration-driven MEMS lead zirconate titanate $Pb(Zr,Ti)O_3$ (PZT) cantilever device is developed for energy harvesting application. This paper presents a piezoelectric based energy harvester which is suitable for power generating from conventional vibration and has in providing energy for low power electron ic devices. The PZT cantilever is used d33 mode to get the electrical power. The PZT cantilever based energy harvester with the dimension of 7 mm${\times}$3 mm${\times}$0.03 mm is fabricated using micromachining technologies. This PZT cantilever has the mechanical resonance frequency with a 900 Hz. With these conditions, we get experimentally the 37 uW output power from this device with the application of 1g acceleration using the 900 Hz vibration. From this study, we show the feasibility of one of energy harvesting candidates using PZT based structure. This PZT energy harvester could be used for various applications such a batteryless micro sensors and micro power generators.

• 전기학회논문지
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• 제56권8호
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• pp.1430-1435
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• 2007

We developed a 440MHz surface acoustic wave (SAW) microsensor integrated with pressure-temperature sensors and ID tag. Two piezoelectric substrates were bonded, in which ${\sim}150\;{\mu}m$ cavity was structured. Four sides were completely sealed by JSR photoresist (PR). Pressure sensor was placed on the top substrate, whereas ill tag and temperature sensor were placed on the bottom substrate. Using network analyzer, the developed microsensor was wirelessly tested. Sharp reflection peaks with high S/N ratio, small signal attenuation, and small spurious peaks were observed. All the reflection peaks were well matched with the coupling of mode (COM) simulation results. With a 10mW RF power from the network analyzer, a ${\sim}1$ meter readout distance was observed. Eight sharp ON reflection peaks were observed for ID tag. Temperature sensor was characterized from $20^{\circ}C$ to $200^{\circ}C$. A large phase shift per unit temperature change was observed. The evaluated sensitivity was ${\sim}10^{\circ}/^{\circ}C$.

• 마이크로전자및패키징학회지
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• 제12권3호
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• pp.267-274
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• 2005

This paper presents the fabrication of surface acoustic wave (SAW)-based pressure sensor for long-term stable mechanical compression force measurement. SAW pressure sensor has many attractive features for practical pressure measurement: no battery requirement, wireless pressure detection especially at hazardous environments, and easy other functionality integrations such as temperature, humidity, and RFID. A $41^{\circ}$ YX $LiNbO_3$ piezoelectric substrate was used because of its high SAW propagation velocity and large values of electromechanical coupling factors $K^2$. A silicon substrate with $\~200{\mu}m$ deep cavity was bonded to the diaphragm with epoxy, in which gold was covered all over the inner cavity in order to confine electromagnetic energy inside the sensor, and provide good isolation of the device from its environment. The reflection coefficient $S_{11}$ was measured using network analyzer. High S/N ratio, sharp reflected peaks, and clear separation between the peaks were observed. As a mechanical compression force was applied to the diaphragm from top with extremely sharp object, the diaphragm was bended, resulting in the phase shifts of the reflected peaks. The phase shifts were modulated depending on the amount of applied mechanical compression force. The measured $S_{11}$ results showed a good agreement with simulated results obtained from equivalent admittance circuit modeling.