Passive Broadband Harmonic Sensor-Tag using Circular Disk Dipole Antenna

The proposed passive chipless harmonic RFID tag composed of single antenna is able to produce transmissionzero depending on the built-in sensor voltage. To allow wide frequency shift, a circular-disk dipole antenna with broadband characteristics is employed. All the circuits are designed as sufficiently small to be built on its one-side element disk. For basic consideration, a variable DC-voltage source is used as an equivalent model of sensors. As described in this paper, characteristics of the antenna and circuit examined in 2.45 GHz/4.9 GHz band are presented through an electromagnetic simulation and a RF-circuit simulation with harmonic balance method, and partially measurements.