Full-duplex communications with the use of parasitic array radiators

Full duplex (FD) communications have been brought into the center of the research activity as an effective way to increase spectral efficiency. This study introduces a novel antenna cancellation technique with the use of a parasitic antenna array at the FD transceiver. Elaborate Multiple-Input-Multiple-Output (MIMO) techniques that use parasitic arrays, such as Beamspace MIMO, have been recently proposed. These techniques use the variable reactances of the loads of the parasitic elements to increase channel capacity with the use of compact antennas and limited number of Radio Frequency (RF) chains. This study proposes a technique that can achieve high isolation of the transmitting and receiving elements of the FD transceiver and simultaneously beamform in order to improve signal reception with dynamic adaptation of the parasitic element load values. The performance of the technique was evaluated with simulation. Results show that the use of parasitic arrays in FD transceivers can drastically reduce the self-inflicted interference, improve overall reception and provide radio channels with FD operation support.