A dual-port reader antenna based on magnetic coupling in near-field (NF) and linear polarization in far-field (FF) is proposed for UHF RFID multiservice applications. The prototype consists of four straight dipoles fed by double-side parallel stripline structure with two feed ports. The proposed antenna can operate at different modes by feeding each corresponding port. In NF mode, a strong and uniform magnetic field can be generated over the interrogation zone. In FF mode, a linearly polarized performance can be obtained. The antenna prototype is printed onto a piece of FR4 substrate with an overall size of 180 × 180 × 1.6 mm3. The measured tests on reading range are carried out, and the results exhibit 100% reading rate for near-field tags within 100 mm and reading distance of far-field tags is 120 cm. Both simulated and measured results show good capability for near- and far-field applications.
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