Polarization Reconfigurable Antenna Based on SIW Cavity for mmWave Applications

This paper proposed a low-profile, compact polarization reconfigurable antenna based on the SIW cavity. A PIN diode is placed in the L-shape slot to switch between linear and circular polarization when the diode is turned on and off, respectively. The simulated results confirm the success of the topology in polarization conversion. The proposed antenna has a wide bandwidth of 3.6 GHz (from 20.7 GHz to 24.3 GHz) with linear polarization and stable gain from 5.0 dBi to 5.8 dBi. The circular polarization is realized at 22 GHz with a broad bandwidth spanning from 20.3 GHz to 24.3 GHz (4 GHz) and a steady gain from 6.2 dBi to 7.3 dBi. The proposed design is promising for mm-wave and 5G applications for various wireless communications scenarios.