2,425 research outputs found
Resource allocation in OFDMA networks with half-duplex and imperfect full-duplex users
Recent studies indicate the feasibility of in-band fullduplex (FD) wireless
communications, where a wireless radio transmits and receives simultaneously in
the same band. Due to its potential to increase the capacity, analyzing the
performance of a cellular network that contains full-duplex devices is crucial.
In this paper, we consider maximizing the weighted sum-rate of downlink and
uplink of a single cell OFDMA network which consists of an imperfect FD
base-station (BS) and a mixture of half-duplex and imperfect full-duplex mobile
users. To this end, the joint problem of sub-channel assignment and power
allocation is investigated and a two-step solution is proposed. A heuristic
algorithm to allocate each sub-channel to a pair of downlink and uplink users
with polynomial complexity is presented. The power allocation problem is
convexified based on the difference of two concave functions approach, for
which an iterative solution is obtained. Simulation results demonstrate that
when all the users and the BS are perfect FD nodes the network throughput could
be doubled, Otherwise, the performance improvement is limited by the inter-node
interference and the self-interference. We also investigate the effect of the
self-interference cancellation capability and the percentage of FD users on the
network performance in both indoor and outdoor scenarios.Comment: 6 pages, 8 figures, Accepted in IEEE International Conference on
Communication (ICC), Malaysia, 201
In-Band Full-Duplex Communications for Cellular Networks with Partial Uplink/Downlink Overlap
In-band full-duplex (FD) communications have been optimistically promoted to
improve the spectrum utilization in cellular networks. However, the explicit
impact of spatial interference, imposed by FD communications, on uplink and
downlink transmissions has been overlooked in the literature. This paper
presents an extensive study of the explicit effect of FD communications on the
uplink and downlink performances. For the sake of rigorous analysis, we develop
a tractable framework based on stochastic geometry toolset. The developed model
accounts for uplink truncated channel inversion power control in FD cellular
networks. The study shows that FD communications improve the downlink
throughput at the expense of significant degradation in the uplink throughput.
Therefore, we propose a novel fine-grained duplexing scheme, denoted as
-duplex scheme, which allows a partial overlap between uplink and
downlink frequency bands. To this end, we show that the amount of the overlap
can be optimized via adjusting to achieve a certain design objective.Comment: To be presented in IEEE Globecom 201
Passive Loop Interference Suppression in Large-Scale Full-Duplex Cellular Networks
Loop interference (LI) in wireless communications, is a notion resulting from
the full-duplex (FD) operation. In a large-scale network, FD also increases the
multiuser interference due to the large number of active wireless links that
exist. Hence, in order to realize the FD potentials, this interference needs to
be restricted. This paper presents a stochastic geometry model of FD cellular
networks where the users and base stations employ directional antennas. Based
on previous experimental results, we model the passive suppression of the LI at
each FD terminal as a function of the angle between the two antennas and show
the significant gains that can be achieved by this method. Together with the
reduction of multiuser interference resulting from antenna directionality, our
model demonstrates that FD can potentially be implemented in large-scale
directional networks.Comment: to appear in Proc. IEEE SPAWC 201
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