Antenna Array Excited by Spoof Planar Plasmonic Waveguide

This letter presents an efficient and simple way to excite a microstrip patch antenna array in K-band. This array is formed by a spoof planar plasmonic waveguide for excitation and several circular patches for radiation. The optimized proposed 2 x 4 patch array, operating in 18.1 similar to 19.4 GHz, features an average gain of 15.2 dBi with a maximum of 16.5 dBi at 18.2 GHz. An experiment was performed, and the measured results prove validity of the design. This method opens up a new kind of feeding method for patch antenna array, which can be broadly engineered in millimeter-waves (MMW) region even to terahertz (THz) region.