In this paper, a broadband reader antenna is designed and manufactured for wearable ankle strap applications. The frequency range covered for S11 < -10 dB is from 850 MHz to 1650 MHz with dipole like radiation pattern in free space. The proposed broadband antenna is manufactured with a semi-flex (Taconic RF-35) and flexible (Kapton) substrates. A good agreement between simulations and measurements has been achieved. Prototypes performances have been tested by measuring the reading distance. The maximum reading distance obtained is about 1.46 m at 865 MHz with an output power of the transmitter (PTX) of 25 dBm. Results of functional RFID test show that the proposed antenna can be used as an RFID reader antenna when it is placed on the ankle of the human body.
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