51,947 research outputs found
A Multi-Game Framework for Harmonized LTE-U and WiFi Coexistence over Unlicensed Bands
The introduction of LTE over unlicensed bands (LTE-U) will enable LTE base
stations (BSs) to boost their capacity and offload their traffic by exploiting
the underused unlicensed bands. However, to reap the benefits of LTE-U, it is
necessary to address various new challenges associated with LTE-U and WiFi
coexistence. In particular, new resource management techniques must be
developed to optimize the usage of the network resources while handling the
interdependence between WiFi and LTE users and ensuring that WiFi users are not
jeopardized. To this end, in this paper, a new game theoretic tool, dubbed as
\emph{multi-game} framework is proposed as a promising approach for modeling
resource allocation problems in LTE-U. In such a framework, multiple,
co-existing and coupled games across heterogeneous channels can be formulated
to capture the specific characteristics of LTE-U. Such games can be of
different properties and types but their outcomes are largely interdependent.
After introducing the basics of the multi-game framework, two classes of
algorithms are outlined to achieve the new solution concepts of multi-games.
Simulation results are then conducted to show how such a multi-game can
effectively capture the specific properties of LTE-U and make of it a
"friendly" neighbor to WiFi.Comment: Accepted for publication at IEEE Wireless Communications Magazine,
Special Issue on LTE in Unlicensed Spectru
Two theoretical dimensions of the cyber hate crime
The impact and relationship between technologies and society establish the development of certain adaptive models, based on coexistence (Human-information-Machine), as well as several behavioral and cognitive changes of the human being, and new models of influence and social control through ubiquitous communication. which is the basis of a new social units called "virtual communities". The rupture of social norms that accompanies rapid social change, and subsequently the appearance of sub-cultural values establishes gaining status of participation in criminal activities, the components of social unites in general conform to social norms by social ties. the individuals or groups see themselves unfairly disadvantaged compared to other similar individuals, within physical-cybernetic ecosystem environment, which supports the interconnection and transformation of social phenomenon of digital dimension, with several implications in cyber hate crime. Thereby establishing the theoretical basis for further research looking which social vulnerability, identify the trajectory of the massive vector of impact "Information", which is a component of social cybernetics from the following three dimensions: (P) Propagation - (R) Replica - (C) Control called the "Cyber Hate Crime Pathway" that links hate crimes within the cyber-physical ecosystem, and where different types of social vulnerability are established. This study incorporates an epistemology approach of the relation between social and cybernetic theories, that will allow establishing a scientific base for future research in the field of new phenomena that will continue to appear within the Physical-Cybernetic ecosystem. It will also allow the contributions and implications to science derived from the product of this research establish a global holistic field applied to criminal justice system, academic and the new entities of social cybernetic
Improving Macrocell - Small Cell Coexistence through Adaptive Interference Draining
The deployment of underlay small base stations (SBSs) is expected to
significantly boost the spectrum efficiency and the coverage of next-generation
cellular networks. However, the coexistence of SBSs underlaid to an existing
macro-cellular network faces important challenges, notably in terms of spectrum
sharing and interference management. In this paper, we propose a novel
game-theoretic model that enables the SBSs to optimize their transmission rates
by making decisions on the resource occupation jointly in the frequency and
spatial domains. This procedure, known as interference draining, is performed
among cooperative SBSs and allows to drastically reduce the interference
experienced by both macro- and small cell users. At the macrocell side, we
consider a modified water-filling policy for the power allocation that allows
each macrocell user (MUE) to focus the transmissions on the degrees of freedom
over which the MUE experiences the best channel and interference conditions.
This approach not only represents an effective way to decrease the received
interference at the MUEs but also grants the SBSs tier additional transmission
opportunities and allows for a more agile interference management. Simulation
results show that the proposed approach yields significant gains at both
macrocell and small cell tiers, in terms of average achievable rate per user,
reaching up to 37%, relative to the non-cooperative case, for a network with
150 MUEs and 200 SBSs
LTE Spectrum Sharing Research Testbed: Integrated Hardware, Software, Network and Data
This paper presents Virginia Tech's wireless testbed supporting research on
long-term evolution (LTE) signaling and radio frequency (RF) spectrum
coexistence. LTE is continuously refined and new features released. As the
communications contexts for LTE expand, new research problems arise and include
operation in harsh RF signaling environments and coexistence with other radios.
Our testbed provides an integrated research tool for investigating these and
other research problems; it allows analyzing the severity of the problem,
designing and rapidly prototyping solutions, and assessing them with
standard-compliant equipment and test procedures. The modular testbed
integrates general-purpose software-defined radio hardware, LTE-specific test
equipment, RF components, free open-source and commercial LTE software, a
configurable RF network and recorded radar waveform samples. It supports RF
channel emulated and over-the-air radiated modes. The testbed can be remotely
accessed and configured. An RF switching network allows for designing many
different experiments that can involve a variety of real and virtual radios
with support for multiple-input multiple-output (MIMO) antenna operation. We
present the testbed, the research it has enabled and some valuable lessons that
we learned and that may help designing, developing, and operating future
wireless testbeds.Comment: In Proceeding of the 10th ACM International Workshop on Wireless
Network Testbeds, Experimental Evaluation & Characterization (WiNTECH),
Snowbird, Utah, October 201
Dilemma between new and existing technologies: Separation and coexistence of old and new technologies in the Television Development Division of Sony Corporation
Regarding R&D management for long-term coexistence of new and existing businesses within a company in technological transition, development of high technology introduces conflict between existing low and medium technologies (LMT). One solution, organizational separation of old and new technologies, can render the technological resources of separated R&D groups mutually inaccessible, thereby possibly necessitating duplication of investment costs. That situation might be prevented by brief coexistence of separate groups during a transition period. Nevertheless, existing businesses based on LMT often retain large markets despite the success of new businesses. In the television business described herein, a technological shift began in the late 1990s to replace conventional CRT televisions with flat panel displays (FPD), including LCDs and plasma display panels (PDPs). Today, despite great interest in FPD televisions, global shipments in 2006 included 130 million CRT televisions and 46 million FPD televisions. Varying unit prices prevent a simple comparison, but CRT televisions constitute a large, fiercely competitive market. Continued coexistence of old and new businesses demands the contradictory conditions of independence of the two R&D groups while using mutual resources. Sony's case has revealed a single technical development division serving both old and new R&D groups, providing similar new technology for product development while co-ordinating these divisions' interests. The technical development division integrates technological and product development to integrate developed technologies into downstream product development. This integration process, so-called integration of old and new R&D technologies, incorporates lower divisions' technology and expertise into technological development, thereby enabling multiple downstream product development groups to acquire technology and expertise through technology that is integrated with that of other product divisions. The process' implications include the following. New businesses use existing business technology; existing businesses can incorporate new technology.Viewing technological changes as diversification, existing and new businesses can increase opportunities through co-operation.Integration of old and new R&D technologies, Low and medium technologies, Conventional resources, Separated organization, Electronics industry
Next-generation optical access seamless Evolution: concluding results of the European FP7 project OASE
Increasing bandwidth demand drives the need for next-generation optical access (NGOA) networks that can meet future end-user service requirements. This paper gives an overview of NGOA solutions, the enabling optical access network technologies, architecture principles, and related economics and business models. NGOA requirements (including peak and sustainable data rate, reach, cost, node consolidation, and open access) are proposed, and the different solutions are compared against such requirements in different scenarios (in terms of population density and system migration). Unsurprisingly, it is found that different solutions are best suited for different scenarios. The conclusions drawn from such findings allow us to formulate recommendations in terms of technology, strategy, and policy. The paper is based on the main results of the European FP7 OASE Integrated Project that ran between January 1, 2010 and February 28, 2013
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