696 research outputs found
Competitive Assessments for HAP Delivery of Mobile Services in Emerging Countries
In recent years, network deployment based on High Altitude Platforms (HAPs)
has gained momentum through several initiatives where air vehicles and
telecommunications payloads have been adapted and refined, resulting in more
efficient and less expensive platforms. In this paper, we study HAP as an
alternative or complementary fast-evolving technology to provide mobile
services in rural areas of emerging countries, where business models need to be
carefully tailored to the reality of their related markets. In these large
areas with low user density, mobile services uptake is likely to be slowed by a
service profitability which is in turn limited by a relatively low average
revenue per user. Through three architectures enabling different business roles
and using different terrestrial, HAP and satellite backhaul solutions, we
devise how to use in an efficient and profitable fashion these multi-purpose
aerial platforms, in complement to existing access and backhauling satellite or
terrestrial technologies
Rate Optimal design of a Wireless Backhaul Network using TV White Space
The penetration of wireless broadband services in remote areas has primarily
been limited due to the lack of economic incentives that service providers
encounter in sparsely populated areas. Besides, wireless backhaul links like
satellite and microwave are either expensive or require strict line of sight
communication making them unattractive. TV white space channels with their
desirable radio propagation characteristics can provide an excellent
alternative for engineering backhaul networks in areas that lack abundant
infrastructure. Specifically, TV white space channels can provide "free
wireless backhaul pipes" to transport aggregated traffic from broadband sources
to fiber access points. In this paper, we investigate the feasibility of
multi-hop wireless backhaul in the available white space channels by using
noncontiguous Orthogonal Frequency Division Multiple Access (NC-OFDMA)
transmissions between fixed backhaul towers. Specifically, we consider joint
power control, scheduling and routing strategies to maximize the minimum rate
across broadband towers in the network. Depending on the population density and
traffic demands of the location under consideration, we discuss the suitable
choice of cell size for the backhaul network. Using the example of available TV
white space channels in Wichita, Kansas (a small city located in central USA),
we provide illustrative numerical examples for designing such wireless backhaul
network
Context-Awareness Enhances 5G Multi-Access Edge Computing Reliability
The fifth generation (5G) mobile telecommunication network is expected to
support Multi- Access Edge Computing (MEC), which intends to distribute
computation tasks and services from the central cloud to the edge clouds.
Towards ultra-responsive, ultra-reliable and ultra-low-latency MEC services,
the current mobile network security architecture should enable a more
decentralized approach for authentication and authorization processes. This
paper proposes a novel decentralized authentication architecture that supports
flexible and low-cost local authentication with the awareness of context
information of network elements such as user equipment and virtual network
functions. Based on a Markov model for backhaul link quality, as well as a
random walk mobility model with mixed mobility classes and traffic scenarios,
numerical simulations have demonstrated that the proposed approach is able to
achieve a flexible balance between the network operating cost and the MEC
reliability.Comment: Accepted by IEEE Access on Feb. 02, 201
Control-data separation architecture for cellular radio access networks: a survey and outlook
Conventional cellular systems are designed to ensure ubiquitous coverage with an always present wireless channel irrespective of the spatial and temporal demand of service. This approach raises several problems due to the tight coupling between network and data access points, as well as the paradigm shift towards data-oriented services, heterogeneous deployments and network densification. A logical separation between control and data planes is seen as a promising solution that could overcome these issues, by providing data services under the umbrella of a coverage layer. This article presents a holistic survey of existing literature on the control-data separation architecture (CDSA) for cellular radio access networks. As a starting point, we discuss the fundamentals, concepts, and general structure of the CDSA. Then, we point out limitations of the conventional architecture in futuristic deployment scenarios. In addition, we present and critically discuss the work that has been done to investigate potential benefits of the CDSA, as well as its technical challenges and enabling technologies. Finally, an overview of standardisation proposals related to this research vision is provided
Interference Management in 5G Reverse TDD HetNets with Wireless Backhaul: A Large System Analysis
This work analyzes a heterogeneous network (HetNet), which comprises a macro
base station (BS) equipped with a large number of antennas and an overlaid
dense tier of small cell access points (SCAs) using a wireless backhaul for
data traffic. The static and low mobility user equipment terminals (UEs) are
associated with the SCAs while those with medium-to-high mobility are served by
the macro BS. A reverse time division duplexing (TDD) protocol is used by the
two tiers, which allows the BS to locally estimate both the intra-tier and
inter-tier channels. This knowledge is then used at the BS either in the uplink
(UL) or in the downlink (DL) to simultaneously serve the macro UEs (MUEs) and
to provide the wireless backhaul to SCAs. A geographical separation of
co-channel SCAs is proposed to limit the interference coming from the UL
signals of MUEs. A concatenated linear precoding technique employing either
zero-forcing (ZF) or regularized ZF is used at the BS to simultaneously serve
MUEs and SCAs in DL while nulling interference toward those SCAs in UL. We
evaluate and characterize the performance of the system through the power
consumption of UL and DL transmissions under the assumption that target rates
must be satisfied and imperfect channel state information is available for
MUEs. The analysis is conducted in the asymptotic regime where the number of BS
antennas and the network size (MUEs and SCAs) grow large with fixed ratios.
Results from large system analysis are used to provide concise formulae for the
asymptotic UL and DL transmit powers and precoding vectors under the above
assumptions. Numerical results are used to validate the analysis in different
settings and to make comparisons with alternative network architectures.Comment: 14 pages, 12 figures. To appear IEEE J. Select. Areas Commun. --
Special Issue on HetNet
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