• 한국전자파학회논문지
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• 제14권9호
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• pp.979-984
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• 2003

인체에 사용되는 삽입형 안테나가 새롭게 제안되었다. 이 안테나의 동작 주파수는 2.45 GHz이며, coaxial cable과 리엑턴스 성분으로 구성되어 있다. 이 리엑턴스 성분은 안테나 끝에 존재하며 거의 완전한 정합과 가열되는 영역을 넓히는데 기여한다. 완전한 안테나 정합을 위하여 전송선로 이론에 기초한 정합방법을 제시하였고 그 정합 방법을 이용하여 이 안테나가 근육에 삽입되었을 때 완전한 정합이 이루어지도록 안테나를 제작, 실험하였다. 측정된 반사계수는 -28.377 dB로써, 지금까지 문헌에 보고된 가장 좋은 결과이다. 그렇기 때문에, 하나의 안테나로도 간, 뇌, 심장과 같이 인체 깊숙이 존재하는 종양이나, 암 세포를 제거하는데 사용될 수 있음을 보여주고 있다.

• Journal of electromagnetic engineering and science
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• 제18권2호
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• pp.117-128
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• 2018

In this paper, compact linear dual polarized series-fed $1{\times}2$ linear and $2{\times}2$ planar arrays antennas for airborne SAR applications are proposed. The proposed antenna design consists of a square radiating patch that is placed on top of the substrate, a quarter wave transformer and $50-{\Omega}$ matched transformer. Matching between a radiating patch and the $50-{\Omega}$ microstrip line is accomplished through a direct coupled-feed technique with the help of an impedance inverter (${\lambda}/4$ impedance transformer) placed at both horizontal and vertical planes, in the case of the $2{\times}2$ planar array. The overall size for the prototype-1 and prototype-2 fabricated antennas are $1.9305{\times}0.9652{\times}0.05106{{\lambda}_0}^3$ and $1.9305{\times}1.9305{\times}0.05106{{\lambda}_0}^3$, respectively. The fabricated structure has been tested, and the experimental results are similar to the simulated ones. The CST MWS simulated and vector network analyzer measured reflection coefficient ($S_{11}$) results were compared, and they indicate that the proposed antenna prototype-1 yields the impedance bandwidth >140 MHz (9.56-9.72 GHz) defined by $S_{11}$<-10 dB with 1.43%, and $S_{21}$<-25 dB in the case of prototype-2 (9.58-9.74 GHz, $S_{11}$< -10 dB) >140 MHz for all the individual ports. The surface currents and the E- and H-field distributions were studied for a better understanding of the polarization mechanism. The measured results of the proposed dual polarized antenna were in accordance with the simulated analysis and showed good performance of the S-parameters and radiation patterns (co-pol and cross-pol), gain, efficiency, front-to-back ratio, half-power beam width) at the resonant frequency. With these features and its compact size, the proposed antenna will be suitable for X-band airborne synthetic aperture radar applications.