Full-Duplex Relaying: Enabling Dual Connectivity via Impairments-Aware Successive Interference Cancellation

In this paper, we address the problem of resource allocation for a full duplex (FD)-enabled relaying system, where a massive multiple-input-multiple-output (mMIMO) multi-carrier (MC) base station (BS) communicates with a single antenna node, employing orthogonal frequency division multiplexing (OFDM). In particular, we consider a scenario that simultaneously activates the relay as well as the direct channel for communicating separate data streams, by employing successive interference cancellation (SuIC) at the end-user. In addition to the superior performance under various system conditions, the proposed dual-connectivity enjoys higher robustness when one of the active paths experience an unexpected blockage. In this regard, we formulate a joint power and subcarrier allocation problem to maximize the total sum rate by considering limited hardware and channel state information (CSI) accuracy. An iterative solution is proposed for the non-convex underlying problem, following the successive inner approximation (SIA) framework, with a guaranteed convergence to a solution satisfying the Karush–Kuhn–Tucker (KKT) optimality conditions. Numerical results show performance gain of our proposed SuIC scheme in terms of sum rate compared to single-connectivity and half duplex (HD) schemes.