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Performance analysis, resource allocation and optimization of cooperative communication systems

The doctoral dissertation of MSc Mulugeta K. Fikadu explores the challenges of implementing future green communication networks and investigates how cooperative networks can be a key enabling technology due to their energy-, space- and cost-efficiency qualities.

Future wireless networks are expected to support high-speed data transmission, efficient wireless access, high-quality services and reliable network coverage while ensuring reduced processing time and power consumption. However, the currently witnessed scarcity of the fundamental radio resources constitutes a significant challenge to satisfying these demands. Furthermore, besides the spatial restrictions, most wireless devices, such as terminals of mobile cellular, ad-hoc and wireless sensor networks, are typically powered by small energy-constrained batteries whose replacement is a rather difficult and costly procedure.

Multi-antenna communications is one of the well researched schemes for increasing the wireless network capacity and reliability. However, this typically comes at the cost of complex transceiver circuitry and a large amount of signal processing power. A robust strategy to deal with these conflicting requirements is to investigate and  implement cooperative networks without the need of installing multiple antennas in hand-held terminals, while still being able to provide high end-to-end performance and minimum energy consumption for transmitting information successfully.

Mulugeta Fikadu’s  doctoral dissertation develops novel analytic tools for investigating the end-to-end performance of dual-hop regenerative cooperative systems with arbitrary spatial correlation and multi-relay regenerative cooperative networks over realistic fading conditions. Furthermore, Mulugeta’s dissertation examines and develops comprehensive energy efficiency optimization models for dual-hop regenerative cooperative systems with spatial correlation effects and optimal power allocation strategies for the regenerative multi-relay cooperative networks over practical fading models.

Mulugeta’s doctoral dissertation also develops analytic tools for examining the end-to-end performance of full-duplex regenerative cooperative systems under the effects of relay self-interference and interference from the direct link over generalized asymmetric fading scenarios. The dissertation also carries out comprehensive, optimal power allocation and energy efficiency optimization for full-duplex and half-duplex regenerative systems. Overall, the guidelines and outcomes of the work are of high importance for the future green communication networks.  

Public defence of a doctoral dissertation on Wednesday, 29 June

The doctoral dissertation of MSc Mulugeta K. Fikadu in the field of communications engineering entitled ‘Performance Analysis, Resource Allocation and Optimization of Cooperative Communication Systems under Generalized Fading Channels’ will be publicly examined at the Faculty of Computing and Electrical Engineering of Tampere University of Technology (TUT) in room TB109 in the Tietotalo building (address: Korkeakoulunkatu 1, Tampere, Finland) at 12 noon on Wednesday, 29 June 2016.

The opponent will be Professor Jyri Hämäläinen from Aalto University. Professor Mikko Valkama from the Department of Electronics and Communications Engineering at TUT will act as Chairman.

Mulugeta K. Fikadu comes from Addis Ababa, Ethiopia and now lives in Tampere, Finland.

Further information: Mulugeta Fikadu, +358 (0) 447069369,
The dissertation is available online at:

News submitted by: Tiina Leivo
Keywords: science and research, cooperative communication systems