그림 1. 시스템 개념도 Fig. 1. System conceptual diagram.
그림 2. 안테나 구조 Fig. 2. Antenna structure.
그림 3. 기생 패치에 의한 대역폭 변화 Fig. 3. Bandwidth variation due to parasitic patch.
그림 4. HR 변화에 따른 반사손실 특성 Fig. 4. Return loss characteristic with respect to HR variation.
그림 5. HD 변화에 따른 반사손실 특성 Fig. 5. Return loss characteristic with respect to HD variation.
그림 6. WD 변화에 따른 반사손실 특성 Fig. 6. Return loss characteristic with respect to WD variation.
그림 7. WP 변화에 따른 반사손실 특성 Fig. 7. Return loss characteristic with respect to WP variation.
그림 8. tc 변화에 따른 반사손실 특성 Fig. 8. Return loss characteristic with respect to tc variation.
그림 9. 제작된 안테나 사진 Fig. 9. Photograph of the manufactured antenna.
그림 10. 최적화된 안테나의 반사손실 Fig. 10. Return loss of the optimized antenna.
그림 11. 915 MHz 복사패턴 Fig. 11. Radiation pattern at 915 MHz.
그림 12. 최적화된 안테나의 전류밀도 Fig. 12. Current distribution of the optimized antenna.
그림 13. 근접한 콘크리트판에 따른 반사손실 특성 Fig. 13. Return loss characteristic with respect to approximate concrete slab.
그림 14. 콘크리트 두께에 따른 반사손실 특성 Fig. 14. Return loss characteristic with respect to concrete thickness.
그림 15. 제작된 콘크리트 블록 Fig. 15. Photograph of the manufactured concrete block.
그림 16. 함수율 변화에 따른 반사손실 특성 Fig. 16. Return loss characteristic with respect to moisture content.
그림 17. 함수율 변화에 따른 915 MHz 복사특성 Fig. 17. Radiation pattern at 915 MHz with respect to moisture content.
표 1. 함수율에 따른 콘크리트 유전율 변화[15] Table 1. Variation of concrete dielectric permittivity with moisture content(weather).
표 2. 최적화된 안테나 설계 변수 Table 2. The design parameter of the optimized antenna.
표 3. 측정된 안테나 이득 Table 3. Measured antenna gain.
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