Defence of dissertation in the field of Communications Engineering M.Sc. (Tech.) Inam Ullah
The title of thesis is “Performance Analysis of Resource Allocation and Interference Mitigation for Inband Decode and Forward Relaying”
Relay Enhanced Cellular (REC) concept provides a promising extension for the 4G and 5G mobile communication systems. This thesis focuses on the performance analysis of inband half-duplex dual-hop DF relaying under the overlaying macro-cellular network.
First, we consider Resource Allocation (RA) between the Relay Link (RL) and the Access Link (AL) that comprise together the end-to-end (e2e) between UE and eNB. We carry out a comparative study of different RA schemes, with focus in resource optimal RA. Results show that RA is essential for the performance of DF relay systems. The (resource) optimal RA clearly improves the e2e relaying performance but requires exchange of fast scheduling information.Second, we study the interference mitigation in RL. We propose a simple beamforming technique with limited side information to mitigate the interference in RL. Performance results, based on analytic formulas, show that especially in Rician channel the interference mitigation can be effectively executed with only few bit side information from relay to the interfering base station. The mitigation of RL interference improve clearly the e2e data rate. Third, a case study on the use of outdoor nomadic relay for the in-building coverage improvement is carried out. This problem can be relaxed by employing nomadic relay that is brought close to the site of an emergency.
Results from the mentioned studies show that relaying provides an effective concept to enhance mobile systems coverage and capacity. Yet, from e2e performance point of view it is of crucial importance that special care is spent on the RA between RL and AL, and on the RL interference mitigation. It was also found that a nomadic relay admit good potential when temporary coverage and capacity boost is needed in a local area.
Opponent: Professor Mohammed Elmusrati, University of Vaasa, Finland
Custos: Professor Jyri Hämäläinen, Aalto University School of Electrical Engineering, Department of Communications and Networking.
Contact information: Inam Ullah, +358458999370, firstname.lastname@example.org, Maarintie 6, 02150, Espoo, Finland.
Venue: Aalto University School of Electrical Engineering, Maarintie 8, hall TU1