A Monopole Antenna With Reconfigurable Circular Polarization and Pattern Tilting Ability in Two Switchable Wide Frequency Bands

In this letter, a simple, planar monopole antenna is proposed to achieve compound reconfigurability. Reconfigurable properties of operating frequency,polarization, and radiation pattern are achieved by the structural reconfiguration of both monopole element and ground plane with the help of only 8 p-i-n diodes. The tilting of the antenna radiation pattern can be reconfigured in between -30° and +30°. In each direction, frequency can be reconfigured in between sub-6 GHz band for future 5G application centered around 3.5 GHz and WLAN band centered around 5.5 GHz. Circularly polarized radiations having opposite polarization states are obtained from these two bands. Moreover, state of polarization is opposite in between radiation patterns having tilt angle of -30° and +30°. Proposed antenna has four reconfigurable states and it can be applicable in cognitive radio and MIMO system.