CPW‐FED rectangular microstrip ring antenna for suppression of parasitic backside radiation

A coplanar waveguide (CPW)‐fed rectangular microstrip ring antenna is proposed and developed for effective suppression of parasitic backside radiation, and is constructed on the basis of a simple slot‐to‐strip EM coupling principle. Due to the non‐radiative behavior of a CPW short‐end feeding block, this antenna allows us to realize an excellent unidirectional radiation pattern. With the use of our developed fullwave method of moments–short‐open calibration (MoM–SOC) technique, its electrical performance such as input impedance and radiation pattern are extensively investigated in theory. Obtained results demonstrate well that the front‐to‐back radiation ratio of our concern is consistently higher than 30 dB while its narrow bandwidth is incremented twice by simply widening its strip width.