Wire-Based Passive Dipole Harmonic Tags for Harmonic Doppler Radar Applications

Abstract

The design, operation along with verifying measurement for a wire-based harmonic tags for use in harmonic Doppler radar applications are presented. The tags are based on the concept of a wire dipole antenna and diode, along with additional wire-based passive components to improve the impedance matching. The tags are designed to receive an incident 2.5 GHz signal that is passed through a non-linear element generating harmonics. The second harmonic is retransmitted through by a section of the antenna tuned to 5 GHz, and captured by a harmonic radar. Wire-based reactive components are designed and implemented to improve the impedance matching. Three different designs are presented, with measured received signals and calculated efficiencies. The tags present a low-cost method of implementing harmonic Doppler detection of moving tagged objects.