Single-Layer Broadband Endfire Antenna with High-Gain and Stable Beams Based on Spoof Surface Plasmon Polaritons

Abstract

A single-layer broadband endfire antenna with high-gain and stable beams based on the spoof surface plasmon polaritons (SSPPs) is proposed in this letter. The amplitude and phase of the surface wave are controlled by asymmetric protrusions on both sides. The anti-symmetric structure is added to balance the upper and lower electric fields while adjusting the impedance matching at the same time. Eventually, endfire radiation is generated with a stable beam to the free space within 5.25-7.94 GHz to form a relative bandwidth of 40.8%. The maximum achieved gain is 11.7 dBi at 7.1 GHz. The experimental results are basically consistent with the simulations. The antenna with high-gain, broadband and a stable beam can be effectively used in wireless communication systems.