Distributed Coding and Modulation for 2-hop Communication via Relays

The past few decades have seen tremendous growth in the field of wireless communication systems. At this juncture, just before the advent of the 4th Generation of mobile standards, the question asked is how to improve the system in terms of coverage, capacity and reliability for the cell-edge users in a cellular network. Providing answers to this question could result in a significant improvement in the average throughput of the cell. The main purpose of the thesis work is therefore to implement Cooperative Communication via Distributed System of Relays. This concept is derived from the combination of relaying technology and multiple antenna techniques used in MIMO systems. During this thesis work, two transmit diversity schemes: the Delay Diversity Scheme and the Distributed Alamouti Scheme are developed on a 3GPP LTE compliant platform described as the OpenAir Interface. The ultimate objective is basically to improve the system performance by exploiting macro-diversity gains obtained as a result of these schemes. In the process of this development, numerous challenging tasks are provided with efficient solutions and have been implemented. Moreover, the last but the most crucial task of the thesis is to develop an entirely new HARQ protocol for a distributed system of relays. The work has been carried out at Eurecom, France as an initial step to implement the aforementioned schemes on a real-time network

Radio Resource Management for Efficient Deployment of Advanced Technologies with Evolution of LTE

Cellular networks have been rapidly evolving to improve the system's spectral efficiency and provide high data rates. 3GPP-based cellular networks have evolved with the release of new additional specifications from LTE in Release 8 to LTE-Advanced in Release 10 and most recently to LTE-Advanced Pro in Release 13. These markers are indications of major enhancements in LTE cellular networks. In order to enable this evolution, it is required to not only improve existing technologies, but introduce novel technologies. However, introducing new technologies from theory to practical systems is non-trivial due to real-world constraints. Combining a number of techniques makes it possible to abridge the gap between theoretically proven research and marketable technology. In this doctoral thesis, the key aspects of radio resource management techniques are studied, investigated and more advanced techniques are proposed to enable efficient integration of new technologies into 3GPP LTE cellular networks. Specifically, the thesis addresses the four primary aspects related radio resource management. Firstly, interference coordination via dynamic scheduling in multi-user MIMO system are studied, with the key motivation to improve the practical gains of MU-MIMO in a constrained environment. Secondly, synchronization procedures in device-to-device communication for faster timing and frequency synchronization between the devices is investigated. Thirdly, resource allocation for signaling overhead to enable massive carrier aggregation is studied. Lastly, medium access (MAC) layer scheduling framework issues are addressed for a multi-user multi-flow traffic scenario in modern wireless networks. The new proposed methods and techniques are compared in terms of respective performance metrics for each of the aforementioned technologies. The 3GPP LTE framework is utilized to conduct both system and link level simulations to examine the performance of proposed techniques in a practical constrained environment. Most of the simulation assumptions are based on 3GPP agreements such that the techniques and their results are valid according to research and industrial standards