Low CQI user focused adaptive scheduling mechanism for LTE networks

In 21th century, world is evolved in to all-connected environment. Now, communication is not limited to people interaction. All devices varying from coffee machines to Da Vinci surgery robots are connected and communicating with others. In addition, people in the world more mobile than they have ever been before. Enhanced transportation facilities allows people travel around the world for business or private purposes. This evolution leads to the requirement of people being connected while they are mobile. Therefore, today telecommunication technologies are in massive development with progressive speed. Starting from 1979 with commercial use of first generation cellular mobile technologies in Japan, four generation of cellular technologies are presented until today for commercial use and developments are ongoing for the fifth generation. In this thesis, commercially latest and fourth generation(4G) mobile communication system named Long Term Evolution (LTE) is introduced as the first section. The network architecture of LTE is presented with core network, radio access network structure with illustrations and critical components. Next, radio interface and protocol design of LTE are presented. In last part, Long Term Evolution Advanced (LTE-A) is demonstrated with major improvements. The aim of LTE introduction section is to provide background information about fourth generation mobile telecommunication technologies as basis knowledge to other sections of the thesis. In the second section, scheduling in LTE system is widely presented. First, brief information and main architecture are given over a simplified model of a packet scheduler. Subsequently, scheduling algorithm types in the literature are introduced with their calculation metrics. In the third part, essentials to design a scheduling algorithm are explained with their impact on performance. The latest part of the section describes the performance indicators with their formulation. Subsequent section presents the proposed scheduling algorithm. Firstly, the design objectives are explained in accordance with main requirements. Then architecture of the new design clarified with detailed information and process flow. In simulation section, detailed information about simulation environment named Vienna LTE-A System Level Simulator given initially. After, implementation of the desired algorithm in the simulation environment is circumstantiated. In results and analysis section, simulation results for the solution provided by thesis are presented with performance indicator analysis and comparisons with algorithms in the literature. Results obtained from the simulations indicate that proposed method reaches thesis goal form various aspects. Using mechanism proposed, allocation interval of the user is increased in frequency and edge throughput that shows data rates for users with inferior channel status enhanced to better figures. Considering the outputs it can be derived that area of research in this study has various developable approaches. Some of these improvement areas are adaptive automation of proposed algorithm for varying network conditions and traffic type sensitive execution of the proposed algorithm.