30 research outputs found
On the Spectral Efficiency and Fairness in Full-Duplex Cellular Networks
To increase the spectral efficiency of wireless networks without requiring
full-duplex capability of user devices, a potential solution is the recently
proposed three-node full-duplex mode. To realize this potential, networks
employing three-node full-duplex transmissions must deal with self-interference
and user-to-user interference, which can be managed by frequency channel and
power allocation techniques. Whereas previous works investigated either
spectral efficient or fair mechanisms, a scheme that balances these two metrics
among users is investigated in this paper. This balancing scheme is based on a
new solution method of the multi-objective optimization problem to maximize the
weighted sum of the per-user spectral efficiency and the minimum spectral
efficiency among users. The mixed integer non-linear nature of this problem is
dealt by Lagrangian duality. Based on the proposed solution approach, a
low-complexity centralized algorithm is developed, which relies on large scale
fading measurements that can be advantageously implemented at the base station.
Numerical results indicate that the proposed algorithm increases the spectral
efficiency and fairness among users without the need of weighting the spectral
efficiency. An important conclusion is that managing user-to-user interference
by resource assignment and power control is crucial for ensuring spectral
efficient and fair operation of full-duplex networks.Comment: 6 pages, 4 figures, accepted in IEEE ICC 2017. arXiv admin note: text
overlap with arXiv:1603.0067
Design and Analysis of Full-Duplex Massive MIMO Cellular Networks
This paper provides a theoretical framework for the study of full-duplex (FD) massive multiple-input multiple-output (MIMO) cellular networks over Rician self-interference (SI) and Rayleigh intended and other-interference fading channels. To facilitate bi-directional wireless functionality, we incorporate (i) a downlink (DL) linear zero-forcing with self-interference-nulling (ZF-SIN) precoding scheme at the FD base stations (BSs), and (ii) an uplink (UL) self-interference-aware (SIA) fractional power control mechanism at the FD user equipments (UEs). Linear ZF receivers are further utilized for signal detection in the UL. The results indicate that the UL rate bottleneck in the baseline FD single-antenna system can be elevated by several hundred times via exploiting massive MIMO. On the other hand, the findings may be viewed as a reality-check as the largest spectral efficiency gain from the FD massive MIMO cellular network over its half-duplex (HD) counterpart under state-of-the-art system parameters is shown to be in the region of ~40%