An Approximate Circuit Model to Analyze Microstrip Rampart Line in OSB Suppressing

An approximate circuit model to analyze microstrip rampart line in open-stopband (OSB) suppressing is presented. The proposed antenna consists of periodically orthogonally bending microstrip transmission line, and the widths of two transversal lines are adjusted to match the input impedance of the unit cell to the characteristic impedance of the transmission line. The approximate circuit model is presented to analyze the behavior of the PLWA. The prototype antenna shows a seamless frequency scanning from 3.7 to 6.8 GHz with a scanning range of 118° from the backward to forward quadrant. The simulation and measured results have demonstrated that the OSB is successfully suppressed in the improved case.