Investigation of dipole antenna based sensor for passive wireless structural health monitoring

摘要

In this paper, feasibility of a wireless mechanical strain sensor based on dipole antenna is investigated. The geometry, deformation and load impedance of feeding lines for dipole antenna can change the electromagnetic resonance frequency, magnitude of resonance and phase angle of antenna. Planar dipole antenna is designed for X band and made on a flexible polymer substrate is fabricated using a conventional photolithography process. Fabricated dipole antenna is attached to a plastic cantilever beam. The return loss of the dipole antenna sensor is characterized using a network analyzer. The strain sensitivity of the sensor is tested by correlating the return loss variation with the bending strain of the cantilever beam.