A CPW-Fed Square-Ring Slot Antenna With Reconfigurable Polarization

A polarization reconfigurable square ring-slot antenna design is proposed. Besides possessing the advantages such as ease in manufacturing and small-size (50 mm
$\times50$
mm
$\times0.8$
mm), due to having a simple biasing circuit, the proposed ring-slot antenna is able to control the PIN diodes with ease, allowing it to switch between linear polarization and left-/right-hand circular polarizations (CP). From the measurement results, the left- and right-hand CP bandwidths (approximately 8.77%, 2290–2520 MHz) of this proposed ring-slot antenna can satisfy the TD-LTE2300 and WLAN2.4GHz operating bands.