Full duplex assisted interference suppression for underlay device-to-device communications

The paper considers underlay Device-to-Device (D2D) communications in a cellular network, where a pair of D2D users communicates subject to the interference from the base station that is transmitting to a cellular user in the downlink. To mitigate the interference while not affecting the performance of the cellular user, a full duplex (FD) assisted interference suppression mechanism is introduced and optimized. The key idea is to exploit the FD capability of the D2D transmitting user to send the desired signal and forward the received interference simultaneously to the D2D receiving user. We obtain the explicit expression of the optimal transmitted signal for the D2D link, and analyze the asymptotical performance of the proposed scheme in high signal-to-noise ratio regime. Simulations validate our analytical results and demonstrate a noticeable performance gain of the proposed FD assisted scheme over the conventional half-duplex scheme.