6,961 research outputs found
Rethinking the role of interference in wireless networks
This article re-examines the fundamental notion of interference in wireless networks by contrasting traditional approaches to new concepts that handle interference in a creative way. Specifically, we discuss the fundamental limits of the interference channel and present the interference alignment technique and its extension of signal alignment techniques. Contrary to this traditional view, which treats interference as a detrimental phenomenon, we introduce three concepts that handle interference as a useful resource. The first concept exploits interference at the modulation level and leads to simple multiuser downlink precoding that provides significant energy savings. The second concept uses radio frequency radiation for energy harvesting and handles interference as a source of green energy. The last concept refers to a secrecy environment and uses interference as an efficient means to jam potential eavesdroppers. These three techniques bring a new vision about interference in wireless networks and motivate a plethora of potential new applications and services
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
On the effect of blockage objects in dense MIMO SWIPT networks
Simultaneous information and power transfer (SWIPT) is characterised by the
ambiguous role of multi-user interference. In short, the beneficial effect of
multi-user interference on RF energy harvesting is obtained at the price of a
reduced link capacity, thus originating nontrivial trade-offs between the
achievable information rate and the harvestable energy. Arguably, in indoor
environments, this trade-off might be affected by the propagation loss due to
blockage objects like walls. Hence, a couple of fundamental questions arise.
How much must the network elements be densified to counteract the blockage
attenuation? Is blockage always detrimental on the achievable rate-energy
trade-off? In this paper, we analyse the performance of an indoor
multiple-input multiple-output (MIMO) SWIPT-enabled network in the attempt to
shed a light of those questions. The effects of the obstacles are examined with
the help of a stochastic approach in which energy transmitters (also referred
to as power heads) are located by using a Poisson Point Process and walls are
generated through a Manhattan Poisson Line Process. The stochastic behaviour of
the signal attenuation and the multi-user interference is studied to obtain the
Joint Complementary Cumulative Distribution Function (J-CCDF) of information
rate and harvested power. Theoretical results are validated through Monte Carlo
simulations. Eventually, the rate-energy trade-off is presented as a function
of the frequency of walls to emphasise the cross-dependences between the
deployment of the network elements and the topology of the venue
- …