자기 에너지를 이용한 지중 SAW 온도센서 구동 및 무선 측정 시스템 개발

다국어 초록 (Multilingual Abstract)

A wireless underground sensor system was developed based on magnetic antennas and surface acoustic wave (SAW) resonator to monitor temperature variations around buried utilities. A~250 ㎒ magnetic antenna generates a SAW along the piezoelectric substrate, and the returned SAW energy owing to the reflection bars on the sensor is reconverted to magnetic flux by the sensor’s interdigital transducer (IDT) and subsequently transmitted to a reader via magnetic antenna. By observing changes in the center frequency of the SAW sensor with temperature, we were able to monitor the underground temperature variations in real time. Temperature sensor was fabricated on a 128o YX LiNbO₃. In soil testing, a long readout distance was observed. The temperature sensors provided stable performance in terms of underground temperature changes, soil type, and soil compactness. The sensitivity and linearity for the sensor was 0.3 ㎒/℃ and 0.96, respectively.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. COMSOL 시뮬레이션 및 Coupling of Mode(COM) 모델링을 통한 시스템 최적화
• 3. NiFe 자기코어 공정 최적화
• 4. 제작
• 5. 결과
• 6. 결론
• References

참고문헌 (Reference)

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