Weighted Sum Rate Maximization in Full-Duplex Multi-User Multi-Cell MIMO Networks

Abstract

In this paper we focus on a multiuser multi-cell scenario with full-duplex (FD) base-stations (BSs) and halfduplex (HD) downlink (DL) and uplink (UL) users, where all nodes are equipped with multiple antennas. Our goal is to design filters for weighted sum rate (WSR) maximization whilst taking into consideration the effect of transmitter and receiver distortion. Since WSR problems are non-convex we exploit the relationship between rate and mean squared error (MSE) in order to propose low complexity alternating optimization algorithms which are guaranteed to converge. While the initial design assumes perfect channel state information (CSI), we also move beyond this assumption and consider WSR problems under imperfect CSI. This is done using two types of error models; the first is a norm-bounded error model, suitable for cases where the CSI error is dominated by quantization issues, and the second is a stochastic error model, suitable for errors that occur during the channel estimation process itself. Results show that rates achieved in FD mode are higher than those achieved by the baseline HD schemes and demonstrate the robust performance of the proposed imperfect CSI designs. Additionally we also extend our original WSR problem to one which maximizes the total DL rate subject to each UL user achieving a desired target rate. This latter design can be used to overcome potential unfairness issues and ensure that all UL users are equally served in every time slot.

Joint Power Control and User Association for NOMA-Based Full-Duplex Systems

“…On the other hand, it can be seen that both ICA-CR based algorithms deviate only 1% ∼ 2% from the optimal SE, meaning that In Fig. 4(a), we plot the average SE versus the number of antennas at the BS, N ∈ [6,16]. First, for small N (i.e., N ≤ 6), ICA-CR based schemes provide the same performance (even worse) compared to the conventional ones.…”

“…On one hand, FD-based systems have been developed primarily for small-cell setups. The authors in [15] and [20] first studied the SE maximization problem for a small-cell FD system under the assumption of perfect channel state information (CSI), and the worst-case robust design for FD multi-cell system was considered in [16]. The application of FD radio to other designs is presently an emerging subject; e.g., the FD-based energy harvesting design [18], [26] and the FD-based physical layer security (PLS) design [19].…”

“…From the discussions above, the successive convex program to solve (12) at iteration κ + 1 is given as (16), (18), (19), (23), (24), (27), (31),…”

Max-Min Fairness User Scheduling and Power Allocation in Full-Duplex OFDMA Systems

“…In the FD cellular networks, multiple-antenna techniques have been applied to the FD systems to overcome the CCI [9]- [14]. Specifically, references [9]- [11] studied the beamforming designs for mitigating the SI and the CCI in the multi-user systems, in order to maximize the network sum rate, the proportional fairness rate, and the max-min fairness (MMF) rate, respectively. Besides, [12]- [14] considered designing the beamformers which satisfy the quality-of-service constraints in the multi-user system or the multiple-input multiple-output interference channel.…”

“…According to (9) to (11), when α i = 1, the binary variable x jib = 0 for all i, j ∈ M, b ∈ B, which implies that UE i must consistently be a downlink UE for all allocated RBs. Similarly, when α i = 0, UE i can never be assigned as a downlink UE.…”