Low-profile shared Shinkansen antenna for overhead line voltage detection and wireless communication

Abstract

This study significantly reduces the height of a shared antenna for overhead line voltage detection and wireless VHF band communication installed on the roof of the Shinkansen vehicle. We propose an antenna configuration employing an inverted-F antenna utilizing a wide-shaped branching element with a notched tip that can maintain antenna performance, even if the height of the antenna is significantly lower. It was proven that the notch at the tip improves average gain in the horizontal plane by 2.3dB and 3.9dB at two operating frequencies, respectively. In addition, the deterioration of the overhead line voltage detection sensitivity was only 30% even though the antenna height was lowered by approximately 72%. To put this antenna to practical use, it is necessary to verify the usage environment and vehicle mounting conditions.