Fence loaded antenna coupler for high-band UWB with steep cutoff characteristics

Abstract

This paper presents a fence-type virtual short stub loaded UWB antenna coupler which has broadband and steep cutoff characteristics at both the lower and upper cutoff frequency. The fence-type short stub consists of a top and bottom metal layers of FR4 substrate and Through Holes (THs) connecting layers. Thanks to this geometry, resonance and anti-resonance occur at various frequencies in several signal paths. The size of the antenna is 1cm × 1cm. The simulation result of coupling coefficient parameter (S21) is higher than -20dB from 6.2GHz to 10.4GHz (4.2GHz bandwidth) when the distance between two couplers is 1cm.