An Ultra-Wideband Circular Ring Monopole Antenna with Reconfigurable Patterns

摘要

A planar ultra-wideband circular ring monopole antenna with reconfigurable patterns is presented. The proposed antenna consists of a circular ring which is used as a driver and two parasitic elements used as either reflector or director and eight p-i-n diode switches. The proposed antenna is designed to reconfigure its radiation pattern in such a manner that it can direct its maximum gain in a particular direction and minimizing the unwanted interference from the other directions without changing the impedance bandwidth of the antenna. By using the different states of the switches the three different operating modes of the antenna can be realized one is monopole and other are two directional mode with opposite directions. Due to the property of pattern diversity, it can enhance the front end flexibility in multipath environments and can be a good candidate for cognitive radio (CR) applications.