Bandwidth Enhancement of a Printed Slot Antenna with a Diamond-Shaped Tuning Stub

Abstract—A printed slot antenna fed by a microstrip line with a diamond-shaped tuning stub for bandwidth enhancement is proposed and experimentally validated. Impedance bandwidth, radiation pattern, and gain characteristics of the proposed antenna are investigated. The simulated results show that the impedance matching of the proposed rotated slot antenna is greatly affected by the dimension of the slot and by the size and the position of the diamond-shaped tuning stub. The experimental results demonstrate that this antenna exhibits an ultra-wide impedance bandwidth, which is over 123% for |S11 | ≤ −10 dB ranging from 2.80 to 11.81GHz. Moreover, a stable and omnidirectional radiation pattern is observed within the operating bandwidth. 1