Integration of microfluidic channels with frequency selective surfaces for sensing and tuning

A two dimensional perturbed Frequency Selective Surface (FSS) with enhanced near-fields has been used for microwave sensing applications. The perturbation causes the scattering by the perturbed array, within a frequency range to be dominated by an odd mode which gives rise to a sharp resonance with a seven-fold near field enhancement compared to the unperturbed array. The spectral shift of the odd resonance is studied for small variations of the electric permittivity of the supporting substrates. The aperture FSS is shown theoretically to increase the sensor sensitivity. The FSS is integrated with a microfluidic channel inside a waveguide simulator to ease the fabrication process and the performance of the ensemble is investigated for different samples inside the channel.