A wideband dual polarized in-band full duplex antenna with higher order modes suppression

Abstract This paper presents a wideband dual-polarized in-band full duplex antenna which can also suppress the higher order modes. A dual differential capacitive feeding scheme is proposed to increase the isolation between the co-located transmitter and receiver ports. The proposed design uses λ /4 resonators in close vicinity of the radiating patch to provide spurious-free characteristics. Further, a parasitic patch placed above the radiating patch at height “ h ” is used to enhance the input matching, impedance bandwidth, and gain of the proposed design. The key features of the proposed structure are its wide impedance bandwidth (∼20%), high inter-port isolation (>58 dB) throughout the entire operating frequency range (2.26–2.76 GHz), and simultaneous suppression of higher order modes which makes it a suitable candidate for modern wireless application. Finally, a prototype is fabricated and measurement results are in good agreement with simulation results.