Design of very small UWB monopole antenna with reconfigurable band-notch performance

In this paper, a compact reconfigurable ACS fed monopole antenna with size of 6.3×12 mm² that has a capability to operate in the ultrawideband (UWB) frequency band with reconfigurable one or two notched band (the rejected bands cover the frequency bands ranging from 3.5 to 4 GHz and 5.15 to 5.825 GHz) is presented. The antenna consist of a simple rectangle patch with folded shape stub and slit as band rejecting elements. The band reject reconfigurable ability is achieved via two RF p-i-n diode switches that positioned in the rejecting elements. The proposed technique offers the solution to the problem encountered in existing reconfigurable antennas which serve only one frequency band at a time. A good agreement is found between the simulated and the measured antenna radiation properties. To the authors´ knowledge, a feature of very small size of antenna with good performance is unique to this paper.