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ABSTRACT: Beyond 3rd Generation (B3G) wireless communication systems are comprised from different Radio Access Technologies (RATs) in
order to satisfy all user needs in services. The coexistence of many RATs in the same environment needs advanced network management
systems in order to ensure efficient resources utilization while achieving the best possible Quality of Service (QoS) levels.
Management functionality in the B3G era will have to solve complex problems, due to the existence of versatile options for
satisfying stringent requirements, under difficult environment conditions. The introduction of cognitive systems in the B3G
world is a direction for addressing the complexity, as it will enable reaching decisions faster and more reliably, by considering
also knowledge and experience derived from past interactions of the system with the network environment. Our work presents
an approach for identifying whether a context, encountered by the network segment, has also been dealt in the past. In this
case context knowledge can be exploited for fast and cost efficient network reconfiguration and adaptation to the environment
conditions.
KeywordsCognitive networks-Management functionality-Pattern recognition-Network adaptation
Wireless Personal Communications 04/2012; 55(3):407-440. · 0.46 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: The B3G concept can be realized in two complementary ways. The first solution is the integration of the diverse radio access
technologies into one composite radio environment. The alternative solution is provided by the concept of reconfigurable (adaptive)
networks. Composite radio networks, sometimes also referred to as cooperative networks, jointly handle a difficult condition.
Reconfigurable networks on the other hand, support B3G Systems by providing technologies that enable network elements and
terminals to dynamically adapt to the environment requirements and conditions, in principle, by means of self-management.
This paper provides proof on the business advantages of reconfigurable networks. In this context the paper performs an evaluation
of the investment in both composite radio and reconfigurable networks, presenting a methodology that can be used for the financial
assessment of such networks by applying investment appraisal techniques. Concrete results for both cases are presented and
analyzed. The analysis clearly proves that reconfigurable networks can provide significant business benefits for network operators.
Wireless Personal Communications 04/2012; 51(2):257-282. · 0.46 Impact Factor
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ABSTRACT: Existing and emerging technologies in the areas of mobile computing, wireless communications/networking, sensor and control
devices, context awareness, user interfaces, etc., provide the ground for the support of human activities in a certain space.
More specifically, these recent advances now allow the gradual “disappearance” of computers and/or other end-user devices
into the environment creating a system that can facilitate everyday living. Such an intelligent environment system offers
personalised, context-aware services that can support and improve everyday life. In spite of the large number and variety
of devices, networking technologies and ambient intelligence subsystems there is a lack of a framework that brings the different
relevant actors together and exploits the full potential of emerging technologies to meet the requirements of an intelligent
environment system, not only in the context of the home but also in the corporate and public sectors. Intelligent environments
necessitate new, advanced management mechanisms. This paper presents an approach for a D
istributed Web-based m
a
nagement
f
ramework for ambient reconfigurable services in the i
n
telligent
e
nvironment (DAFNE).
Mobile Networks and Applications 04/2012; 11(6):889-900. · 0.84 Impact Factor
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V. Stavroulaki,
A. Bantouna,
Y. Kritikou,
K. Tsagkaris, P. Demestichas,
P. Blasco,
F. Bader,
M. Dohler,
D. Denkovski,
V. Atanasovski,
L. Gavrilovska
IEEE Vehicular Technology Magazine 01/2012; Vol. 7(Issue 2):pp.91-99.. · 1.23 Impact Factor
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ABSTRACT: The information and communications technologies world is migrating towards the Future Internet (FI) era. Operators will have increased complexity to address in the FI era, compared to today, in the management of their infrastructure and services. This is due to the extended set of applications that should be supported and to the more options offered by the infrastructure. Cognitive management systems are seen as a viable direction for basing the management of the FI era, due to their “self-management” and “learning” features. In this respect, this paper discusses on application and business-driven requirements, the capabilities of the infrastructure, the potentials of cognitive management systems, and challenges that have to be addressed for their introduction.
Personal, Indoor and Mobile Radio Communications Workshops (PIMRC Workshops), 2010 IEEE 21st International Symposium on; 10/2010
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ABSTRACT: The dawn of the Future Internet (FI) era poses new requirements to modern communication networks namely, the demand for new applications/ services, the support for diversified services, the expanded use of wireless access and the need for increased efficiency in resource provisioning and utilization. In this paper we propose a solution to address these requirements. In particular, the proposed solution is based on (i) opportunistic networks, which can be seen as operator-governed, temporary and probably infrastructure-less extensions of the infrastructure-based network, (ii) cognitive systems both for managing the opportunistic networks and for coordinating with the infrastructure, and (iii) control channels for the cooperation of the cognitive management systems. We advocate that the adoption of such a solution will bring about enhanced wireless service provision and extended access capabilities for the Future Internet, through higher resource utilization, lower costs, and management decisions with a larger “green” footprint.
Personal, Indoor and Mobile Radio Communications Workshops (PIMRC Workshops), 2010 IEEE 21st International Symposium on; 10/2010
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ABSTRACT: Wireless communication systems have penetrated into almost all parts of human live. They have become essential and pervasive and do affect both personal and professional aspects of our lives. While most types of wireless networks, such as cellular mobile communication networks, have been exhaustively studied and optimized, in order to handle various situations, there are also contexts, which require efficient handling, e.g. moving hotspots, areas that have lost their infrastructure and areas with hard morphology. The motivation for this work is the efficient handling of these important contexts by the use of Moving Access Points (MAPs). MAPs are capable of autonomously moving and establishing a radio network in short time, with limited centralized management. The radio network provides wireless access to users (based on femtocell concept), is based on ad-hoc connectivity (self-adapting mesh network concept), and has some elements acting as gateways to a wide-area infrastructure. The main purpose of this paper is to find the optimal position of the MAPs i.e. the ones which require minimum movement and telecommunication cost. In order to achieve this goal, an innovative algorithm that combines the well known Simulated Annealing algorithm with the Ant Colony Optimization, is proposed. Finally, the operation of the algorithm is validated through two indicative scenarios, where it is compared to the single Simulated Annealing and the Brute Force method, respectively.
Future Network and Mobile Summit, 2010; 07/2010
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ABSTRACT: The emerging radio landscape will consist of heterogeneous wireless networks, operating in the framework of diverse co-operative associations of network operators, for accommodation of the demands of users with multimode and/or multihoming enabled terminals. In this context, the optimized spectrum and radio resource utilization will be key factor for the accomplishment of the goals of both users and operators, namely the satisfaction of user's needs and the augmentation of operators' profits. The IEEE P1900.4 standardisation group is working towards specifying architectures and functions that will enable networkterminal distributed decision making for optimized radio resource usage in such heterogeneous wireless access networks. In alignment with the recently standardized P1900.4 management architecture, in this paper we set up an experimentation platform and conduct indicative experiments for both the demonstration and performance assessment of the management architecture. The assessment results show satisfactory behavior in terms of induced management signaling loads and time delays, that is equivalent to minimal intervention into the real network operation.
Future Network and Mobile Summit, 2010; 07/2010
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ABSTRACT: The increasing need for mobility has brought about significant changes in transportation infrastructures. Inefficiencies cause enormous losses of time, decrease in the level of safety for both vehicles and pedestrians, high pollution, degradation of quality of life, and huge waste of nonrenewable fossil energy.The scope of this article is to introduce novel functionality for providing knowledge to vehicles, thus jointly managing traffic and safety. This will be achieved through the design of the proposed functionality, which, at a high level, will comprise (1) sensor networks formed by vehicles of a certain vicinity that exchange traffic-related information, (2) cognitive management functionality placed inside the vehicles for inferring knowledge and experience, and (3) cognitive management functionality in the overall transportation infrastructure. The goal of the aforementioned three main components shall be to issue directives to the drivers and the overall transportation infrastructure valuable in context handling.
IEEE Vehicular Technology Magazine 04/2010; · 1.23 Impact Factor
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ABSTRACT: One of the most recent trends in the area of B3G communications are reconfigurable, cognitive systems. Cognitive systems encompass self-management and self-optimization capabilities: awareness of user, device and context information, policies derivation, decision making, reconfiguration and learning. Mechanisms for perception and learning of user and context information are one of the most important features of cognitive systems. Based on the knowledge and experience obtained through learning, cognitive systems can determine and configure their operation not only in a reactive manner, i.e. responding to the detection of problematic situations, but also proactively, so as to prevent issues undermining the optimal system function. This paper presents the approach of the European Union funded project End-to-End Efficiency (E<sup>3</sup>), aiming at integrating cognitive wireless systems in the Beyond the Third Generation (B3G) world.
Personal, Indoor and Mobile Radio Communications, 2009 IEEE 20th International Symposium on; 10/2009
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ABSTRACT: In this paper we discuss on the cognitive management of wireless infrastructures that encompass Flexible Base Stations (FBSs) and Femtocells investigated by the Integrated Project E3 (End-to-End-Efficiency) funded within FP7. FBSs are equipped with Software Defined Radio (SDR) transceivers capable of operating the appropriate Radio Access Technologies (RATs) while Femtocells are capable of changing their operating parameters, including the way to manage the Mobile Terminals (MTs). The necessary reconfiguration actions are provided by the network decision entity called Dynamic Self-organizing Network Planning and Management (DSNPM). DSNPM is enhanced with optimization procedures as well as cognitive functionalities that will provide the means for proper network adaptation to the environment changes in timely manner. Our work presents an approach for the overall optimization procedure, exploiting FBSs and Femtocells software and hardware capabilities as well as knowledge and experience gained from past interactions of DSNPM with the network environment. High level system architecture will be presented describing the problem statement and the solution approach in which the above aspects will be addressed. Finally, an indicative scenario will exhibit the efficiency of FBSs and Femtocells functionalities as well as the associated cognitive management functionalities of DSNPM.
Personal, Indoor and Mobile Radio Communications, 2009 IEEE 20th International Symposium on; 10/2009
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ABSTRACT: Telecommunications and information technology will be parts of the Future Internet infrastructures. It will be characterized by powerful and complex network infrastructures, advanced applications, services and content, efficient power management as well as extensions in the business model. These characteristics entail that the management of the Future Internet world will be more complex, compared to today. The introduction of cognitive systems is believed to be an efficient response to the complexity. In this respect, the aims and contribution of this paper is to provide an approach for realizing the Future Internet era by means of cognitive systems. The basis and foundation will be work conducted in the area of cognitive wireless networks. This work constitutes a solid basis, on which the Future Internet era can be realized, through suitable expansions.
Cognitive Radio Oriented Wireless Networks and Communications, 2009. CROWNCOM '09. 4th International Conference on; 07/2009
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ABSTRACT: Worldwide interoperability for microwave access (WiMax) tends to be one of the most controversial technologies in telecommunications history. WiMax can be seen either as a prominent technology in the mobile Internet access revolution or as an unjustifiably hyped technology that remained just an expectation and never lived up to its potential. Advocates of the former statement include the major, leading industries. There are also significant supporters of the latter one, and thus doubters of WiMAX, which bank on their experience in deploying legacy, cellular networks, and shift the attention to HSxPA and third-generation (3G) long-term evolution (LTE).
IEEE Vehicular Technology Magazine 07/2009; · 1.23 Impact Factor
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ABSTRACT: The continuous evolution of wireless systems has resulted in a number of new and powerful wireless networking standards. The concept of Beyond the Third Generation Systems (B3G) emerged in an attempt to exploit the variety of the available access standards to the benefit of end-users, operators and manufacturers. In this context, a key topic in the research area of B3G/4G networks is related to mechanisms and strategies to efficiently realize the complementary use of the diverse Radio Access Technologies (RATs), through their convergence into one composite radio environment. One of the most important features of these evolving systems is the availability of multiple access technologies, which will allow users to enjoy wireless services at any time, at any place. Evidently in order to truly enhance the experience of all users, even technology agnostic ones, functionality is required, on both the network and the user- device side, for providing the "always best connection" in a transparent manner. The focus of this paper is more on the end- user side. The target is to realize management functionality that takes into account user requirements, environment characteristics, configuration policies and experience established so as to dynamically configure the user terminal in a seamless and transparent manner, through machine learning mechanisms. This can be achieved with the help of Bayesian Networks, a technique used for encoding and learning probabilistic relationships.
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th; 05/2009
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ABSTRACT: With the deployment of next generation (4G) mobile radio systems an additional radio access network is established. A variety of different Radio Access Technologies (RATs) will be operated in parallel. In this framework, the Long Term Evolution (LTE) system, specified by 3GPP, will have to co-exist with WiMAX, mobile 2G/3G networks and Wireless Local Area Networks (WLANs). To cope with this increasing diversity and complexity mechanisms for self-optimisation, self-organisation, self-healing, self-configuration (self-x) are essential to guarantee cost efficient and high quality network operation. Within the project E<sup>3</sup> [1] self-x functionalities for different use cases and different elements of a mobile radio access network are developed. Aim of this paper is to give and overview about the interworking of different self-x functionalities and to present three exemplary use cases.
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th; 05/2009
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ABSTRACT: According to the B3G concept, diverse radio access technologies (RATs) can converge into one composite radio environment, where the user is "always best connected" and can move between the various technologies seamlessly. Cognitive wireless networks [1],[2] have emerged as a complementary concept to B3G networks. In general, cognitive systems establish their behaviour, in a reactive or proactive manner, based on external triggers (environment), as well as their goals, principles (policies, rules), experience and knowledge. This requires, among other things, advanced terminal management functionality for dynamically selecting and adapting to the most appropriate technology, in a seamless, transparent and robust manner. This paper emphasizes on the management of user equipment and discusses on how to further progress the relevant work. The work of this paper complements legacy methods for network selection by presenting cognitive mechanisms and an associated knowledge-based network selection scheme. In particular, a specific learning scheme that relies on the use of Bayesian statistics is proposed. In the direction of assessing the performance of the developed knowledge-based selection scheme a software implementation has been realised. This software implementation also includes a legacy selection scheme thus enabling the comparison with the knowledge-based selection. Corresponding results derived from the software implementation are presented.
Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th; 05/2009
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ABSTRACT: In this article, we propose and describe a functional architecture (FA) for the efficient radio and spectrum resource management of the anticipated future compound communication systems. This work comprises an advancement of the FA that has been initially proposed within end-to-end reconfigurability - phase 2 (E2R II) project and has been enhanced to incorporate cognitive and self-x capabilities to address the newly born B3G challenges. Furthermore, the proposed FA is currently being elaborated within the Working Group 3 (WG3) of the Reconfigurable Radio Systems Technical Committee (RRS TC). This committee was created by European Standards Telecommunication Institute (ETSI) Board with the aim to study the feasibility of standardization activities related to reconfigurable radio systems (including software defined and cognitive radios). It should be also mentioned that a relevant functional architecture for optimized radio resource usage in heterogeneous wireless networks is currently under standardization within IEEE.
IEEE Vehicular Technology Magazine 04/2009; · 1.23 Impact Factor
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ABSTRACT: The continuously increasing need for mobility has brought about not only significant facilities in several aspects of human initiative, but also growing traffic congestions, a phenomenon that leads to unpleasant everyday situations at a short time level, but in the long run also to the degradation of the level of quality of living in large cities and the alienation between people. The management of traffic stands, thus, as a fundamental prerequisite for confronting those issues, enhancing transportation and improving the social fabric. This paper considers the concept of car pooling as a structured approach to this problem, by specifying, developing and validating a mobile-community-driven system for collaborative transportation, namely the ''transportation management-car pooling system''. This system is capable of proposing optimal, reliable and secure community matches (taking into consideration personality features, talking interests, driving style, etc.), based on user profile and context information. The paper describes the transportation management-car pooling system, presenting its input parameters, decision making process and outcomes. Finally, indicative simulation results showcase its effectiveness.
Telematics and Informatics 01/2009; 26(4):375-390.
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ABSTRACT: In this paper, we provide a framework for enhancing radio resource management (RRM) in 3G long term evolution (LTE) systems with cognitive features. By exploiting the capabilities of orthogonal frequency division multiplexing (OFDM) LTE access technology, network segments are capable of properly adapting to the environment conditions by applying RRM algorithms for optimized sub-carriers' assignment, power allocation and adaptive modulation. On the other hand, cognitive features can be used to provide the system with knowledge that derives from past interactions with the environment. As a result, the system will be able to apply already known solutions in timely manner when identifying a problem that has been already addressed in the past. Framed within the above statements, we propose and validate a cognitive RRM scheme in the context of LTE network segments. Indicative examples and results showcase that the proposed scheme can result in significant efficiency improvement in terms of performance and network adaptation.
New Frontiers in Dynamic Spectrum Access Networks, 2008. DySPAN 2008. 3rd IEEE Symposium on; 11/2008
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ABSTRACT: A key topic in the field of future wireless B3G/4G networks is related to mechanisms for the efficient complementary use of the different technologies. The goal is to exploit the multiplicity of the available access standards to the benefit of end-users, operators and manufacturers. The concept of future wireless B3G/4G introduces the idea of diverse, heterogeneous Radio Access Technologies (RATs) able to converge into one composite radio environment, where the user is ldquoalways best connectedrdquo, while the most appropriate technology is selected and applied seamlessly. Cognitive and reconfigurable wireless networks have appeared as a complementary concept to B3G networks. Cognitive systems determine their behaviour, goals, principles, experience and knowledge, reactively or proactively and acting in response to external triggers. The focus of this paper is more on the end-user side. In this sense, the paper presents a Cognitive Terminal Management System (CTMS) that comprises mechanisms for retrieving and managing user information using concepts from Bayesian statistics. The use of Bayesian Networks for the prediction of future user preferences is also addressed in terms of appropriate modelling of the user profile.
Personal, Indoor and Mobile Radio Communications, 2008. PIMRC 2008. IEEE 19th International Symposium on; 10/2008
