루프를 이용한 근거리 RFID 리더 안테나

다국어 초록 (Multilingual Abstract)

This paper proposes a near-field RFID reader antenna based on a loop. The proposed antenna consists of a loop loaded with inductors and resistors, a top ground plane for adjusting the far-field gain, a balun and a metal housing. The near magnetic field is generated by a loop consisting of a circular wire and two orthogonal linear wires. Four inductors are placed on the loop to reduce the loop size and four resistors are used to obtain an impedance matching and to control the near magnetic field strength. A ground plan is placed around the loop to reduce the far-field gain of the antenna. A special balun structure is employed to reduce the radiation from the feeding coaxial cable. The loop and the feeding coaxial cable are placed in a metal housing to produce the near magnetic field only in the region just above the antenna. The antenna is optimally designed using a commercial software, then fabricated and tested. The fabricated antenna has a reflection coefficient less than -10dB over 903-921MHz, a far-field gain of -14.5dB, an H-field of 0.38A/m at 40mm above the antenna surface and a tag read distance up to 630mm when a power of 25dBm is supplied to the antenna.

참고문헌 (Reference)

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