Minimizing power consumption in virtualized cellular networks

Cellular network nodes should be dynamically switched on/off based on the load requirements of the network, to save power and minimize inter-cell interference. This should be done keeping into account global interference effects, which requires a centralized approach. In this paper, we present an architecture, realized within the Flex5GWare EU project, that manages a large-scale cellular network, switching on and off nodes based on load requirements and context data. We describe the architectural framework and the optimization model that is used to decide the activity state of the nodes. We present simulation results showing that the framework adapts to the minimum power level based on the cell loads

Life is short. The impact of power states on base station lifetime

We study the impact of power state transitions on the lifetime of base stations (BSs) in mobile networks. In particular, we propose a model to estimate the lifetime decrease/increase as a consequence of the application of power state changes. The model takes into account both hardware (HW) parameters, which depend on the materials used to build the device, and power state parameters, that instead depend on how and when power state transitions take place. More in depth, we consider the impact of different power states when a BS is active, and one sleep mode state when a BS is powered off. When a BS reduces the power consumption, its lifetime tends to increase. However, when a BS changes the power state, its lifetime tends to be decreased. Thus, there is a tradeoff between these two effects. Our results, obtained over universal mobile telecommunication system (UMTS) and long term evolution (LTE) case studies, indicate the need of a careful management of the power state transitions in order to not deteriorate the BS lifetime, and consequently to not increase the associated reparation/replacement costs

Efisiensi Energi Pada Jaringan Seluler Dengan Teknik Base-Station Sleep-Mode: Studi Literatur

Penggunaan Teknologi Komunikasi pada dekade ini menunjukkan peningkatan trafik data yang sangat signifikan. Dalam hal ini, operator jaringan seluler melakukan inovasi untuk mengurangi jumlah penggunaan energi yang ditimbulkan dari banyaknya jumlah energi yang digunakan tanpa mengurangi quality of service (QoS) kepada costumer. Tujuan pemanfaatan penggunaan energi ini supaya operator jaringan lebih efisiendan tidak mengurangi tingkat efektifitas dalam pemakaian energi yang dikeluarkan. Paper ini menjelaskan mengenai pemakaian jaringan dengan teknologi teknik Base-Station Sleep-Mode. Metode ini akan menjalankan auto controluntuk menjalankan fungsinya pada pemancar jaringan, sehingga dibutuhkan sebuah pendekatan untuk memproses dengan menggunakan parameter-parameter yang dibutuhkan diantaranya User Association, SON (Self-Organizing Network), Cell Zooming, Traffic Prediction, dan Heterogenous Deployment. Salah satu hasil penelitian dari BS Sleeping mode menunjukkan hasil yaitu didapatkan nilai efisiensi energi hingga 90% pada akhir pekan di area bisnis dan perkantoran, dan 30-40%

Cell identification based on received signal strength fingerprints: concept and application towards energy saving in cellular networks

The increasing deployment of small cells aimed at off-loading data traffic from macrocells in heterogeneous networks has resulted in a drastic increase in energy consumption in cellular networks. Energy consumption can be optimized in a selforganized way by adapting the number of active cells in response to the current traffic demand. In this paper we concentrate on the complex problem of how to identify small cells to be reactivated in situations where multiple cells are concurrently inactive. Solely based on the received signal strength, we present cell-specific patterns for the generation of unique cell fingerprints. The cell fingerprints of the deactivated cells are matched with measurements from a high data rate demanding mobile device to identify the most appropriate candidate. Our scheme results in a matching success rate of up to 100% to identify the best cell depending on the number of cells to be activated

A practical framework for energy-efficient node activation in heterogeneous LTE networks

This paper presents a framework to activate and deactivate micro nodes in a heterogeneous multi-cell LTE network, based on load and energy efficiency consideration. The framework exploits historical data (i.e., per-macro-cell load curves) to select a set of candidate switch-on/switch-off instants of micro cells, assuming a limited number of state changes is allowed in a day. The switching instants are instead determined online, by taking into account the actual traffic as well as the load curves. Moreover, intercell interference is fully accounted for. Our simulations show that this framework allows a multi-cell network to sustain peak-hour load when necessary, and to reconfigure to a minimum coverage baseline whenever feasible, thus saving power (up to 25% in our scenarios). Moreover, the framework is robust, meaning that deviations of the actual traffic with respect to the prediction offered by the load curves can easily be handled

Powering remote area base stations by renewable energy

Abstract. The number of cellular subscriptions have seen a tremendous growth in the last decade and to provide connectivity for everyone has led to growth in number of base stations (BSs). BSs installed at places where reliable grid power is not available has increased and will continue to increase in the coming years to connect everybody on the globe. Energy and cost efficiency is becoming a criterion of ever increasing importance in the information and communication technology sector. Energy and cost efficiency is especially important for remote areas where providing mobile communication services is inhibited by the economic drawback of low revenue potential. In this thesis, we discuss the role of BS power consumption in the cellular networks in order to investigate approaches to lower the overall power consumption of the cellular network. The thesis covers structure of a BS and the power consumption of its components. Previous works and research approaches proposed to reduce the power consumption of BSs and to what extent they can lower the power requirement are discussed. Reducing the BS power consumption will reduce the operating cost for the networks and ease the deployment of BSs in remote areas. Also discussed are the two key technical features of 5th generation cellular access networks (beam forming through massive multiple input multiple output antenna systems and ultra-lean system design) that are promising in terms of reducing the BS power consumption. Furthermore, we discuss viable sources of renewable energy that can be used to power BSs in the remote areas. An overview of the renewable energy resources that can be used for this purpose (solar and wind energy) and their availability in different regions is discussed. The setups for harnessing solar and wind energy to generate power are presented in this thesis. For different cases requirements of wind and solar energy systems to power the BSs are calculated. Results show that while solar energy alone is a feasible option in regions at low latitude, small solar energy systems of 4–7 kW rated output power can easily power BS during the entire year. But in regions of high latitude using solar energy alone cannot meet the BS power requirement as there are long durations of very low or negligible solar irradiation levels. Furthermore, the energy produced by small wind energy setups at different wind speeds is investigated for the purpose of powering BSs. We discuss the range of windspeed levels for which the energy produced is sufficient to power a BS. Areas with average windspeeds of 5–8 m/s are very suitable for using wind energy as a source of power for BSs. Hybrid energy systems to power BSs and also a few energy storage options to store excess power are also discussed in this thesis

再生可能エネルギー駆動型無線メッシュネットワークにおける通信と電力効率の最適化に関する研究

Tohoku University加藤寧課