Dual-Dipole UHF RFID Tag Antenna with Quasi-Isotropic Patterns Based on Four-Axis Reflection Symmetry

<table>Structure of the linear dual-dipole tag antenna. The substrate of the antenna is made of PTFE, with an area of <svg height="12.4375" id="M42" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 26.799999 12.4375" width="26.799999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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International Journal of Antennas and Propagation

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Figure 3

Figure 3: Dual-Dipole UHF RFID Tag Antenna with Quasi-Isotropic Patterns Based on Four-Axis Reflection Symmetry 