| 摘要 |
RFID reader antennas and methods for generating magnetic fields. An antenna can be made from conductors that do not contact each other, but have loop portions spatially arranged along a loop section. The loop portions have gaps between them, and thus the loop section is discontinuous. The loop section can be driven from near its ends by a UHF RFID excitation signal, which travels through the loop portions, and also through the gaps because it is AC. Thus an excitation current becomes established along the loop section, which generates a useable magnetic field. Each loop portion can be short, so that the magnetic field it contributes will not self-cancel due to the shorter wavelength of UHF RFID. The loop section can be large independently of the wavelength, so that the magnetic field is of a size large enough to be useful for ILT in RFID.
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