Haas, Harald

Thompson, John

Auer, Gunther

Holtkamp, Hauke Andreas

2014-07-16T15:29:15Z

2014-07-16T15:29:15Z

2014-06-30

This thesis is concerned with the energy efficiency of cellular networks. It studies the dominant power consumer in future cellular networks, the Long Term Evolution (LTE) radio Base Station (BS), and proposes mechanisms that enhance the BS energy efficiency by reducing its power consumption under target rate constraints. These mechanisms trade spare capacity for power saving. First, the thesis describes how much power individual components of a BS consume and what parameters affect this consumption based on third party experimental data. These individual models are joined into a component power model for an entire BS. The component model is an essential step in analysis but is too complex for many applications. It is therefore abstracted into a much simpler parameterized model to reduce its complexity. The parameterized model is further simplified into an affine model which can be applied in power minimization. Second, Power Control (PC) and Discontinuous Transmission (DTX) are identified as promising power-saving Radio Resource Management (RRM) mechanisms and applied to multi-user downlink transmission. PC reduces the power consumption of the Power Amplifier (PA) and is found to be most effective at high traffic loads. DTX mostly reduces the power consumption of the Baseband (BB) unit while interrupting transmission and is better applied in low traffic loads. Joint optimization of these two techniques is found to enable additional power-saving at medium traffic loads and to be a convex problem which can be solved efficiently. The convex problem is extended to provide a comprehensive power-saving Orthogonal Frequency Division Multiple Access (OFDMA) frame resource scheduler. The proposed scheduler is shown to reduce power consumption by 25-40% in computer simulations, depending on the traffic load. Finally, the thesis investigates the influence of interference on power consumption in a network of multiple power-saving BSs. It discusses three popular alternative distributed uncoordinated methods which align DTX mode between neighbouring BSs. To address drawbacks of these three, a fourth memory-based DTX alignment method is proposed. It decreases power consumption by up to 40% and retransmission probability by around 20%, depending on the traffic load.

http://hdl.handle.net/1842/9376

en

The University of Edinburgh

Gunther Auer and Istvan Godor and Laszlo Hevizi and Muhammad Ali Imran and Jens Malmodin and Peter Fasekas and Gergely Biczok and Hauke Holtkamp and Dietrich Zeller and Oliver Blume and Rahim Tafazolli, "Enablers for Energy Efficient Wireless Networks", Proceedings of the IEEE Vehicular Technology Conference (VTC) Fall-2010, 2010

Hauke Holtkamp and Gunther Auer, "Fundamental Limits of Energy- Efficient Resource Sharing, Power Control and Discontinuous Transmission", Proceedings of the Future Network & Mobile Summit 2011, 2011

Hauke Holtkamp and Gunther Auer and Harald Haas, "Minimal Average Consumption Downlink Base Station Power Control Strategy", Proceedings of the 2011 IEEE 22nd International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC), 2011

Hauke Holtkamp and Gunther Auer and Harald Haas, "On Minimizing Base Station Power Consumption", Proceedings of the Vehicular Technology Conference (VTC) Fall-2011, 2011

Claude Desset and Bjorn Debaillie and Vito Giannini and Albrecht Fehske and Gunther Auer and Hauke Holtkamp and Wieslawa Wajda and Dario Sabella and Fred Richter and Manuel Gonzalez and Henrik Klessig and Istvan Godor and Per Skillermark and Magnus Olsson and Muhammad Ali Imran and Anton Ambrosy and Oliver Blume, "Flexible Power Modeling of LTE Base Stations", Proceedings of the 2012 IEEE Wireless Communications and Networking Conference:, 2012

Hauke Holtkamp and Gunther Auer and Samer Bazzi and Harald Haas, "Minimizing Base Station Power Consumption", IEEE Journal on Selected Areas in Communications, 2014

energy efficiency

wireless networks

power consumption

base station

Enhancing the energy efficiency of radio base stations

Thesis or Dissertation

Doctoral

PhD Doctor of Philosophy