A Novel Antenna Design of Compact HF and UHF Passive RFID Tags with Interconnected Structure for Energy Harvesting and Tracking Systems

Figure 2

Simulation results of the rectangular spiral coil tag antenna for HF RFID applications.

(a) Rectangular spiral coil

(b) Input resistance and reactance versus frequency

(c) Magnitude of reflection coefficient versus frequency

(d) Magnetic field intensity at 13.56 MHz