Measured Performance of Broadband Frequency Selective Surface to Reduce Return Loss

Plastic cases of wireless systems causes return loss in millimeter-wave band. A frequency selective surface (FSS) inserted at the center of the dielectric plate controls reflection phase, thus, return loss is canceled for various dielectric thickness in broadband. FSS was designed by transfer matrix (T-matrix) analysis and return loss of the dielectric plate was reduced in broadband. The performance was evaluated by simulations and measurements.