64,828 research outputs found
Network-Assisted Device-to-Device (D2D) Direct Proximity Discovery with Underlay Communication
Device-to-Device communications are expected to play an important role in
current and future cellular generations, by increasing the spatial reuse of
spectrum resources and enabling lower latency communication links. This
paradigm has two fundamental building blocks: (i) proximity discovery and (ii)
direct communication between proximate devices. While (ii) is treated
extensively in the recent literature, (i) has received relatively little
attention. In this paper we analyze a network-assisted underlay proximity
discovery protocol, where a cellular device can take the role of: announcer
(which announces its interest in establishing a D2D connection) or monitor
(which listens for the transmissions from the announcers). Traditionally, the
announcers transmit their messages over dedicated channel resources. In
contrast, inspired by recent advances on receivers with multiuser decoding
capabilities, we consider the case where the announcers underlay their messages
in the downlink transmissions that are directed towards the monitoring devices.
We propose a power control scheme applied to the downlink transmission, which
copes with the underlay transmission via additional power expenditure, while
guaranteeing both reliable downlink transmissions and underlay proximity
discovery.Comment: Accepted for presentation at Globecom 201
A Hybrid Model to Extend Vehicular Intercommunication V2V through D2D Architecture
In the recent years, many solutions for Vehicle to Vehicle (V2V)
communication were proposed to overcome failure problems (also known as dead
ends). This paper proposes a novel framework for V2V failure recovery using
Device-to-Device (D2D) communications. Based on the unified Intelligent
Transportation Systems (ITS) architecture, LTE-based D2D mechanisms can improve
V2V dead ends failure recovery delays. This new paradigm of hybrid V2V-D2D
communications overcomes the limitations of traditional V2V routing techniques.
According to NS2 simulation results, the proposed hybrid model decreases the
end to end delay (E2E) of messages delivery. A complete comparison of different
D2D use cases (best & worst scenarios) is presented to show the enhancements
brought by our solution compared to traditional V2V techniques.Comment: 6 page
CogCell: Cognitive Interplay between 60GHz Picocells and 2.4/5GHz Hotspots in the 5G Era
Rapid proliferation of wireless communication devices and the emergence of a
variety of new applications have triggered investigations into next-generation
mobile broadband systems, i.e., 5G. Legacy 2G--4G systems covering large areas
were envisioned to serve both indoor and outdoor environments. However, in the
5G-era, 80\% of overall traffic is expected to be generated in indoors. Hence,
the current approach of macro-cell mobile network, where there is no
differentiation between indoors and outdoors, needs to be reconsidered. We
envision 60\,GHz mmWave picocell architecture to support high-speed indoor and
hotspot communications. We envisage the 5G indoor network as a combination of-,
and interplay between, 2.4/5\,GHz having robust coverage and 60\,GHz links
offering high datarate. This requires an intelligent coordination and
cooperation. We propose 60\,GHz picocellular network architecture, called
CogCell, leveraging the ubiquitous WiFi. We propose to use 60\,GHz for the data
plane and 2.4/5GHz for the control plane. The hybrid network architecture
considers an opportunistic fall-back to 2.4/5\,GHz in case of poor connectivity
in the 60\,GHz domain. Further, to avoid the frequent re-beamforming in 60\,GHz
directional links due to mobility, we propose a cognitive module -- a
sensor-assisted intelligent beam switching procedure -- which reduces the
communication overhead. We believe that the CogCell concept will help future
indoor communications and possibly outdoor hotspots, where mobile stations and
access points collaborate with each other to improve the user experience.Comment: 14 PAGES in IEEE Communications Magazine, Special issue on Emerging
Applications, Services and Engineering for Cognitive Cellular Systems
(EASE4CCS), July 201
A Novel Device-to-Device Discovery Scheme for Underlay Cellular Networks
Tremendous growing demand for high data rate services such as video, gaming
and social networking in wireless cellular systems, attracted researchers'
attention to focus on developing proximity services. In this regard,
device-to-device (D2D) communications as a promising technology for future
cellular systems, plays crucial rule. The key factor in D2D communication is
providing efficient peer discovery mechanisms in ultra dense networks. In this
paper, we propose a centralized D2D discovery scheme by employing a signaling
algorithm to exchange D2D discovery messages between network entities. In this
system, potential D2D pairs share uplink cellular users' resources with
collision detection, to initiate a D2D links. Stochastic geometry is used to
analyze system performance in terms of success probability of the transmitted
signal and minimum required time slots for the proposed discovery scheme.
Extensive simulations are used to evaluate the proposed system performance.Comment: Accepted for publication in 25'th Iranian Conference on Electrical
Engineering (ICEE2017
Localization and mobility management in heterogeneous wireless networks with network-assistance
The nowadays heterogeneous wireless network (HWN) is a collection of ubiquitous wireless networking elements (WNEs) that support diverse functional capabilities and networking purposes. In such a heterogeneous networking environment, localization and mobility management will play a key role for the seamless support of emerging applications, such as social networking, massive multiplayer online gaming, device-todevice (D2D) communications, smart metering, first-responder communications, and unsupervised navigation of communication-aware robotic nodes. Since most of the existing wireless networking technologies enable the WNEs to assess their current radio status and directly (or indirectly) estimate their relative distance and angle with respect to other WNEs of the same Radio Access Technology (RAT), the integration of such information from the ubiquitous WNEs arises as a natural solution for robustly handling localization between (not necessarily homogeneous) WNEs and mobility management of moving WNEs governed by resource-constrained operation. Under the viewpoint of investigating how the utilization of such spatial information can be used to enhance the performance of localization and mobility management in the nowadays HWN, in this
work we focus and contribute in the following four research areas: i) localization and peer-discovery between non-homogeneous WNEs, ii) network-assisted D2D discovery in cellular networks, iii) energy-efficient handover (HO) decision in the macrocell – femtocell network, and iv) network-assisted vertical handover decision (VHO) for the integrated cellular and WLAN heterogeneous wireless network
Seeing the Unobservable: Channel Learning for Wireless Communication Networks
Wireless communication networks rely heavily on channel state information
(CSI) to make informed decision for signal processing and network operations.
However, the traditional CSI acquisition methods is facing many difficulties:
pilot-aided channel training consumes a great deal of channel resources and
reduces the opportunities for energy saving, while location-aided channel
estimation suffers from inaccurate and insufficient location information. In
this paper, we propose a novel channel learning framework, which can tackle
these difficulties by inferring unobservable CSI from the observable one. We
formulate this framework theoretically and illustrate a special case in which
the learnability of the unobservable CSI can be guaranteed. Possible
applications of channel learning are then described, including cell selection
in multi-tier networks, device discovery for device-to-device (D2D)
communications, as well as end-to-end user association for load balancing. We
also propose a neuron-network-based algorithm for the cell selection problem in
multi-tier networks. The performance of this algorithm is evaluated using
geometry-based stochastic channel model (GSCM). In settings with 5 small cells,
the average cell-selection accuracy is 73% - only a 3.9% loss compared with a
location-aided algorithm which requires genuine location information.Comment: 6 pages, 4 figures, accepted by GlobeCom'1
Radio Link Enabler for Context-aware D2D Communication in Reuse Mode
Device-to-Device (D2D) communication is considered as one of the key
technologies for the fifth generation wireless communication system (5G) due to
certain benefits provided, e.g. traffic offload and low end-to-end latency. A
D2D link can reuse resource of a cellular user for its own transmission, while
mutual interference in between these two links is introduced. In this paper, we
propose a smart radio resource management (RRM) algorithm which enables D2D
communication to reuse cellular resource, by taking into account of context
information. Besides, signaling schemes with high efficiency are also given in
this work to enable the proposed RRM algorithm. Simulation results demonstrate
the performance improvement of the proposed scheme in terms of the overall cell
capacity
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