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Future Network & Mobile Summit (FutureNetw), 2011

Date 15-17 June 2011

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Displaying Results 1 - 25 of 84
  • [Title page]

    Publication Year: 2011 , Page(s): 1
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    Freely Available from IEEE
  • 2011 Future Network & Mobile Summit [Copyright notice]

    Publication Year: 2011 , Page(s): 1
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    Freely Available from IEEE
  • Physical layer amendments for MIMO features in 802.11a

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1330 KB) |  | HTML iconHTML  

    This paper presents enhancements in the physical layer of 802.11a wireless local area networks (WLANs) to support multiple-input multiple-output (MIMO) communication. In this approach, spatial diversity is exploited at the radio-frequency (RF) front-end by weighting the transmitted and the received signals using integrated circuits (ICs). Their optimum weight settings are derived by baseband algorithms based on the estimated MIMO channel response. Prototyping platforms are designed for baseband signal processing and RF transmission, which contain all key components for the RF-MIMO technique and 802.11a data transmission, respectively. The developed algorithms, computing platforms and ICs are successfully verified with respect to the RF-MIMO concept and their compatibility to 802.11a devices. View full abstract»

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  • A scalable solution to provide Quality of Service in Next-Generation Networks

    Publication Year: 2011 , Page(s): 1 - 15
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (365 KB) |  | HTML iconHTML  

    Next-Generation Networks (NGNs) will support Quality of Service (QoS) for multimedia traffic over an IP-based infrastructure. A scalable solution to provide also stringent guarantees is required. DiffServ architecture can offer different levels of service at low complexity, but it is not basically able to efficiently provide end-to-end absolute QoS for real-time traffic. Many research activities have addressed this issue, proposing either an absolute or a relative approach. While the former is complicated to implement in the global Internet, the latter is simpler and can be easily realized without arising scalability concerns because exploiting the Proportional Differentiation Model (PDM), in which the performance distance between classes is proportional to quality differentiation parameters that Network Service Provider (NSP) can configure. This work aims to achieve absolute delay guarantees relying on a PDM that can be easily deployed in DiffServ architecture using a proportional scheduler, like Advanced Waiting Time Priority (AWTP). The key idea is to enhance the end-to-end delay differentiation provided by PDM, with a run-time class adaptation, which dynamically assigns the service class to critical traffic in order to fulfil its end-to-end delay requirements. Simulation results have been collected to analyse the trade-off between the fast reaction to load changes and the system stability with different measurement processes, employed to decide for a class promotion or downgrade. The validity and good performance of our proposal have been demonstrated over various scenarios also in the critical case of network congestion. View full abstract»

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  • Home routing gateway virtualization: An overview on the architecture alternatives

    Publication Year: 2011 , Page(s): 1 - 9
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (127 KB) |  | HTML iconHTML  

    This paper presents a novel concept in home and access network architectures based on the virtualization within the service provider network of the layer-3 home routing gateway functionality. This new paradigm aims to diminish service providers' capital and operational expenditures in home equipment associated to the deployment of services for residential customers, while easing the deployment of new services due to the layer-2 visibility of the home network from the access network. Several architecture designs for this home routing gateway virtualization are presented together with a qualitative comparison among them. Finally, a list of topics for further study in order to make this paradigm a feasible deployment has been elaborated. View full abstract»

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  • Concepts for energy efficient LTE transceiver systems in macro base stations

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (323 KB) |  | HTML iconHTML  

    In today's macro base stations, the transceiver system is one of the most power-consuming components, simply due to low energy efficiency of the power amplifier. The decreased performance in medium and low load situations gives significant room for energy saving. For exploiting this potential, different concepts are proposed by the EARTH project to mitigate the energy wastage in transceiver systems. The deployment of LTE brings the opportunity for using load aware components to minimize the energy consumption, and thereby the CO2 emissions and the operational expenses due to cellular networks. Special attention is paid to optimise the performance in medium and low load scenarios, which occur most of the time. The proposed concept “Signal Load Adaptive Transceiver System”, implements dynamic adaptation of transceiver components to achieve higher energy efficiencies. In this paper, individual concepts for transceiver blocks are presented, the performance improvements are shown by power characteristics of the transceiver system, and the impact on energy efficiency improvement is evaluated by examples based on different application scenarios. View full abstract»

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  • UWB integration into heterogeneous access networks

    Publication Year: 2011 , Page(s): 1 - 9
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    The purpose of this paper is to provide the reader with a vision of the current status of the integration of the Ultra-Wideband (UWB) technology into the heterogeneous access networks. Three different fields have been considered to perform this integration process: user devices, access network equipment and location-aware services. Nowadays user terminals and network devices are equipped with multiple radio interfaces, such as Wi-Fi, UMTS, WiMAX, Bluetooth, but other technologies are expected to be also integrated in the short-term with the objective to offer novel and attractive services. UWB with its lower cost, lower power consumption, higher data rates and better localisation features in relation to present short-range wireless technologies, and LTE as the next radio access interface to be deployed by mobile operators, will play a key role in the development of future multi-radio user devices and network equipment. With the aim of guaranteeing the optimum performance of all these technologies working in close proximity integrated into small-sized multi-interface devices, in this paper, a UWB/UMTS-HSPA collaborative mechanism implemented in a smartphone is described. Moreover, the coexistence between UWB and LTE as well as the interworking between UWB and WiMAX is analysed. The results of the evaluation of WiMedia as a network access technology in picocells are also presented. Finally, the inclusion of UWB in novel location-based services is studied in this document. View full abstract»

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  • Spectrum Aggregation: Initial outcomes from SAMURAI project

    Publication Year: 2011 , Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (352 KB) |  | HTML iconHTML  

    Multi-user MIMO and Spectrum Aggregation (also referred to Carrier Aggregation) are two key enablers of next generation wireless systems. Although those techniques were already quite well investigated at theoretical level, their practical implementation is not immediate and raises numerous challenges. The SAMURAI project aims at investigating such challenges as well as at providing realistic performance results. This paper presents first outcomes of the project, with a specific focus of Carrier Aggregation (CA). Two aspects are discussed: CA at PHY/RF level with implementation challenges. Then, the system aspect of CA, providing new flexibility in terms of radio resource management is investigated. System simulations show capacity improvement when CA is enabled. SAMURAI outcomes in the MU-MIMO aspects are reported in a companion paper [9]. View full abstract»

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  • Maximising average energy efficiency for two-user AWGN broadcast channel

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (201 KB) |  | HTML iconHTML  

    Energy consumption has become an increasingly important aspect of wireless communications, from both an economical and environmental point of view. New enhancements are being placed on mobile networks to reduce the power consumption of both mobile terminals and base stations. This paper studies the achievable rate region of AWGN broadcast channels under Time-division, Frequency-division and Superposition coding, and locates the optimal energy-efficient rate-pair according to a comparison metric based on the average energy efficiency of the system. In addition to the transmit power, circuit power and signalling power are also incorporated in the energy efficiency function, with simulation results verifying that the Superposition coding scheme achieves the highest energy efficiency in an ideal, but non-realistic scenario, where the signalling power is zero. With moderate signalling power, the Frequency-division scheme is the most energy-efficient, with Superposition coding and Time-division becoming second and third best. Conversely, when the signalling power is high, both Time-division and Frequency-division schemes outperform Superposition coding. On the other hand, the Superposition coding scheme also incorporates rate-fairness into the system, which allows both users to transmit whilst maximising the energy efficiency. View full abstract»

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  • On the energy efficiency gain of MIMO communication under various power consumption models

    Publication Year: 2011 , Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (320 KB) |  | HTML iconHTML  

    Along with spectral efficiency (SE), Energy efficiency (EE) is becoming one of the main performance evaluation criteria in communication. These two criteria, which are conflicting, can be linked through their trade-off. As far as MIMO is concerned, a closed-form approximation of the EE-SE trade-off has recently been proposed and it proved useful for analyzing the impact of using multiple antennas on the EE. In this paper, we use this closed-form approximation for assessing and comparing the EE gain of MIMO over SISO system when different power consumption models (PCMs) are considered at the transmitter. The EE of a communication system is closely related to its power consumption. In theory only the transmit power is considered as consumed power, whereas in a practical setting, the consumed power is the addition of two terms; the fixed consumed power, which accounts for cooling, processing, etc., and the variable consumed power, which varies as a function of the transmit power. Our analysis unveils the large mismatch between theoretical and practical EE gain of MIMO over SISO system; In theory, the EE gain increases both with the SE and the number of antennas, and, hence the potential of MIMO for EE improvement is very large in comparison with SISO; On the contrary, the EE gain is small and decreases as the number of transmit antennas increases when realistic PCMs are considered. View full abstract»

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  • Green networking: Integration of wireless sensor network with home gigabit access

    Publication Year: 2011 , Page(s): 1 - 10
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1677 KB) |  | HTML iconHTML  

    Actual home networks have become an heterogeneous environment in terms of technologies used and do not take into account any intelligent energy saving mechanism. In this paper we propose an energy saving strategy by integrating a Wireless Sensor Network (WSN) with a high speed, hybrid home network. The main objective is to demonstrate that a WSN can act as a dependable control plane, where low data rate control packets can flow even when the high speed home network is shut down. While the home network nodes or some of each node's network technologies can be deactivate, the WSN is always on and, due to the low data rate required to properly work, it consumes a very limited quantity of energy. This mutual interaction between the high speed home network and the WSN allows at the same time to achiveve the convergence of heterogeneous communication technologies in the home environment and leads to a substantial reduction of the energy consumptions. Simulation results show that this strategy is effective in a multitude of scenarios and provides a tangible economical benefit. View full abstract»

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  • Key concepts for the Future Internet architecture

    Publication Year: 2011 , Page(s): 1 - 10
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (328 KB) |  | HTML iconHTML  

    The present work introduces a novel approach to cope with the current internet limitations. The need to manage heterogeneous resources, over heterogeneous systems requires a cognitive approach. We propose a cognitive framework based on semantic virtualization of the main internet entities: actors, resources and applications. By means of dynamic generic enablers and proper interfaces, the cognitive framework can operate over heterogeneous environments, translating them into semantic-enriched homogeneous metadata. This virtualization allows the cognitive framework to manage the available resources using advanced, technology independent algorithms. A key role is played by the interfaces which, as the paper shows, can introduce a further cognition level. View full abstract»

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  • Hierarchical Decode & Forward strategy in IR-UWB communication systems

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (262 KB) |  | HTML iconHTML  

    This paper investigates multinode networks based on a Ultra Wideband (UWB) technology. The presence of several simultaneously communicating nodes in the network is not handled by “classical” - orthogonal separation - methods but is based on a novel approach based on information theory. Relay nodes inside the network utilize Hierarchical Decode & Forward (HDF) strategy which is promising to substantially increase the overall throughput of the network. We develop a coding scheme which is aware of the surrounding network structure hence multiuser interferences can be handled in codebooks design procedure. Performance of the proposed coding schemes is verified on the simplest multinode network topologies. A channel capacity was chosen as the performance metric. The capacity is numerically evaluated for real UWB propagation behavior simulated by appropriate channel models. View full abstract»

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  • Multi antenna techniques to improve energy efficiency in LTE radio access network

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (421 KB) |  | HTML iconHTML  

    The main drivers in the design of current radio access networks have been so far coverage and capacity to provide service and a related good quality, but new directions are emerging with growing relevance, both for existing and future networks. Among them energy efficiency is the most relevant and challenging at the same time and innovative networks, besides providing a good quality of service, shall present the minimum energy consumption as well. In this paper, developed in the framework of the EARTH project, beamforming multi antenna techniques are dealt with as possible means to achieve energy savings goals in radio access networks, with particular focus to LTE. Reconfigurable and adaptive antennas are introduced as beamforming multiple antennas solutions, and the concept of active antennas is presented as a feasible implementation for both. Gains in the overall throughput and spectral efficiency are shown, and the related gains in energy efficiency are under evaluation with the adoption of a feasible power model. View full abstract»

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  • Protecting digital identities in future networks

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (362 KB) |  | HTML iconHTML  

    The basic idea behind the locator/identifier separation in network protocols is to differentiate the location (where) from the entity (who) that is taking part in the communication. But the architectures following this idea are finally associating an entity with the particular device it is using to communicate, which means that actual identity behind the device is not considered enough and that its identifier is somehow disclosed. This behavior manifests different problems, like the traceability and overall privacy, and misses the opportunity to involve the actual identity of the different parties in the communication operation. In this paper we propose an architecture to enhance Future Internet by creating a secure and scalable communication infrastructure to build an identity plane that enhances privacy preventing identity traceability while involving identities in the network operation. View full abstract»

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  • Identifying scenarios with high potential for future cognitive radio networks

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (724 KB) |  | HTML iconHTML  

    Opportunistic spectrum access is a great prospect for future wireless networks. The key requirements for an opportunistic user are to avoid interference with any licensed users of the same spectrum and also to cooperate fairly with other opportunistic users. There are many scenarios where an opportunistic network could provide a system that has the potential to provide a better business case than conventional wireless networks. The most promising scenarios for opportunistic users that are on the move and have a requirement for managed quality of service are identified in this paper. The processes used to develop these scenarios are also presented. View full abstract»

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  • Computational complexity analysis of advanced physical layers based on multicarrier modulation

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (970 KB) |  | HTML iconHTML  

    In this contribution we thoroughly analyze the computational effort necessary to implement a multicarrier based physical layer for wireless communications. We consider two variations of this modulation concept, namely traditional cyclic pre-x based orthogonal frequency division multiplexing (CP-OFDM) and lter bank based multicarrier (FBMC) systems. First, we give the analytical formulas for the computational complexity of both systems by taking into account the turbo channel decoding and the multicarrier modulation, demodulation and equalization. Based on the specications of WiMAX, we present a numerical comparison between both systems, where they occupy the same bandwidth and possess the same throughput. From the examples, we can conclude that, for a certain bit error ratio, the two alternatives present a similar computational complexity, but CP-OFDM still has to deploy 1.7 dB more energy per information bit than FBMC in order to achieve the same performance. View full abstract»

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  • Multi-beam assisted MIMO — A novel approach to fixed beamforming

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (245 KB) |  | HTML iconHTML  

    Fourth-generation (4G) wireless networks promise the provision of unprecedented data rates. However apart from achieving a very high headline rate, it is also critical that future systems provide the capacity density of at least 1 Gbit/s/km2 that is expected to be in demand. A promising solution that can provide the needed capacity density uses a large number of narrow beams at the base station with the aid of a Butler matrix. This fixed beamforming approach needs to be enhanced in order to provide the required capacity density as user throughput suffers from inter-beam interference because users are not likely to be located at the boresight of beams. For this purpose we propose that multiple-input multiple-output (MIMO) techniques are applied in the beam domain, resulting in a concept we may describe as multi-beam assisted MIMO (MBA-MIMO). This is shown to effectively mitigate interference and enable the provision of the required capacity density. Therefore MBA-MIMO is an attractive technology that can play a prominent role in future wireless networks beyond 4G. View full abstract»

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  • Testbed federation: An approach for experimentation-driven research in cognitive radios and cognitive networking

    Publication Year: 2011 , Page(s): 1 - 9
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (256 KB) |  | HTML iconHTML  

    The sub-optimal exploitation of radio spectrum is widely accepted. Cognitive radio is a technology that aims to address this issue and improve the overall efficiency of radio spectrum utilization. However, this promising technology is far from being mature at present. In addition to theoretical research, experimentally-driven research is needed to convince industry and regulators of the benefits of cognitive radio. Several initiatives in this direction are taking place or are currently operational in both Europe and the United States. Most of them feature testbeds devoted to a specific radio access technology, network topology or application. A “federation” of testbeds, addressing different applications or technologies each, can offer a richer and more powerful framework to tackle the large variety of challenges of experimentally-driven research in cognitive radio. The approach proposed in this paper combines the existing capabilities of several testbeds to build a “federation”. Through intelligent combination of hardware and software components originating from different testbeds and linking them together via standardized interfaces, new components with enhanced capabilities are created. Another key feature of the “federation” is the establishment of a benchmarking framework, enabling repeatable and reproducible results in a controlled wireless environment and allowing a fair comparison between experiments. View full abstract»

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  • Robust collaborative spectrum sensing based on beta reputation system

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (219 KB) |  | HTML iconHTML  

    Collaborative spectrum sensing has been widely accepted as a promising approach to improve spectrum sensing performance by exploiting spatial diversity of cognitive radio users. However, in the presence of malfunctioning or misbehaved users, performance of collaborative spectrum sensing deteriorates significantly. In this paper, a credibility based mechanism for collaborative spectrum sensing using beta reputation system has been introduced. Our proposed method works well even if the total number of misbehaved users is unknown. In the proposed scheme, fusion center assigns weight to each user observation based on individual user credibility score. User credibility score is calculated using beta reputation system and simulation results show that proposed scheme significantly improves the reliability of aggregated data in the presence of falsified users. View full abstract»

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  • A topic-based, publish-subscribe architecture for intermittently connected 802.15.4 networks

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (312 KB) |  | HTML iconHTML  

    The small size and power consumption of IEEE 802.15.4 devices allows embedding them in GSM/UMTS U-SIM cards and/or SD cards. The availability of such technology for data exchange within mobile phones is very useful to complement GSM/UMTS services, providing proximity services, such as chat and advertisements in a shopping mall, configuration data, micro-payments, access control. In addition, once that we have the availability of a free communication radio link, we can enlarge the assortment of offered services, supporting not only ”direct” data exchanges between two users within the 802.15.4 connectivity range, but also communication among intermittently connected users. This is a typical scenario of so-called Delay Tolerant Networks (DTN) and we argue that a communication paradigm well suited to this environment is publish-subscribe. On the other hand, publish-subscribe is also well suited to satisfy the requirements of a community of users such as the one of an university campus, accompanying other services such as voice and Internet access. The aim of this paper is to present a topic-based, publish-subscribe architecture for intermittently connected networks exploiting IEEE 802.15.4 devices, and taking into due account the severe constraints deriving from their physical characteristics. We describe the architectural model, the protocol design, the system analysis, and the implementation of our solution in a real test-bed, which we carried out in cooperation with Telecom Italia, that financed this work. We point out that our system can be easily adapted to operate in a fully distributed, infrastructure-less way, allowing free communications e.g. in disaster areas or in areas in which ”usual” communications means are either non existent or intentionally made unavailable. For instance, we could realize a server-less version of Twitter able to epidemically distribute information very quickly, provided that we have a high-enough density- - of devices implementing our solution. View full abstract»

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  • Energy-efficient sleeping modes for next-generation core networks

    Publication Year: 2011 , Page(s): 1 - 9
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (754 KB) |  | HTML iconHTML  

    The increased number of devices and links in today's backbones networks of Telecom, in order to maintain quality of service during busy or rush hour loads, has become in a critical factor for the power consumption in communication networks. Unfortunately, current network devices do not have power management primitives, and the energy consumption is largely independent of the load through the devices. Considering these points, we propose a viable approach to introduce and to support standby primitives in backbone network elements, which can be effectively used to almost halve the energy requirements of the whole Telecom core network. Periodic reconfiguration of nodes and links to meet incoming traffic volumes and operational constraints of real-world networks, such as reliability, stability, quality of service, and re-convergence times, is the main idea of the approach that we propose, exploring the main features of backbone device architectures, as well as the network protocol stack. View full abstract»

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  • Opportunities for energy savings in pico/femto-cell base-stations

    Publication Year: 2011 , Page(s): 1 - 8
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (388 KB) |  | HTML iconHTML  

    To support the growth and the dynamism in today's wireless communication, networks are evolving towards smaller cells and base-stations closer to the mobile users. This evolution opens the possibility to deal with one of the main problems in mobile networks: the energy consumption of the base-stations. In this paper, different opportunities are proposed to save energy in small-cell base-stations. These solutions, targeting energy adaptation, focus on the most power greedy components. The energy savings are shown both for the individual components as for a typical pico-cell base-station operating on LTE signals and considering a daily data traffic profile. This offers an average energy saving of 30%, but the flexible nature of the proposed solutions can be further exploited in heterogeneous networks. View full abstract»

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  • TV White Spaces maps computation through interference analysis

    Publication Year: 2011 , Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1153 KB) |  | HTML iconHTML  

    For the characterization of TV White Spaces (TVWS), an extensive simulation of the impact of interfering signals was undertaken in a generalized scenario. The simulation for these investigations was derived from a Monte Carlo methodology using SEAMCAT, and the results include the computation of TVWS maps as it can be done with the access to a geo-location database, or based on autonomous sensing only. Geo-location database approach is shown to utilize TVWS spectrum more efficiently. The impact of Professional Wireless Microphone Systems (PWMS) devices on the availability of TVWS is also analyzed and imposes additional limitations of the maximum power emitted by secondary spectrum users. View full abstract»

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  • Planning and network management for energy efficiency in wireless systems

    Publication Year: 2011 , Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (180 KB) |  | HTML iconHTML  

    This paper presents a cellular network planning concept that contributes to the green network aspect. The presented approach consists of an energy consumption optimizing method that is based on a planning algorithm published formerly. The goal is to optimize network layout taking into account the temporal and spatial variation of traffic demands. Besides serving traffic demands and fulfilling coverage requirements, reducing power consumption is primary goal of the presented procedure. Network management is introduced by means of assuming the possibility of switching off base stations and changing layout by changing main antenna lobe directions, as well as changing transmit power level. Numerical results show these mechanisms effect on network level energy efficiency attained. View full abstract»

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