Two PIN Loaded Inverted L Slot Embedded Polarization Reconfigurable Antenna for WLAN Applications

A simple and compact polarization reconfigurable patch antenna design is proposed to operate in WLAN band at
a resonant frequency of 2.4 GHz. This antenna consists of a rectangular patch placed on an FR4 substrate. A
rectangular slot is cut in the rectangular patch. Two L shaped microstrip strips are placed inside the slot and joined
together at the centre of the rectangular patch by inverting the L shaped microstrip. There are three different methods of achieving the reconfigurability namely electrical, mechanical and optical. This proposed structure uses
electrical reconfiguration technique. This proposed antenna structure uses PIN diodes for achieving the polarization
reconfigurability because of its ease in biasing. Two PIN diodes both being placed on the inverted L shaped structure
in order to achieve the polarization modes and these PIN diodes are used to connect this microstrip with the
rectangular patch. By switching these two PIN diodes for various biasing conditions, four different polarization modes namely two linear polarization (LP) modes, one Left Hand Circular polarization (LHCP) and one Right Hand Circular polarization (RHCP) mode is achieved. The antenna produces simulated gain of around 1.5416 dB for LP1 mode at
2.41 GHz, 1.7175 dB for LP2 mode at 2.45 GHz, 1.6062 dB for RHCP mode and 1.5922 dB for LHCP mode both at 2.4 GHz. The antenna structure is simulated using Ansys HFSS.