Radio Resource Management in Advanced OFDMA-based Cellular Networks

Download or read book Radio Resource Management in Advanced OFDMA-based Cellular Networks written by Rajarajan Sivaraj and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advancements in radio access technologies for 4G+/5G next-generation telecommunication networks are based on the following principles: (i) Bandwidth aggregation, (ii) Network Heterogeneity, (iii) Transmit Diversity and (iv) Spatial Multiplexing. 3GPP Release 10+ specification suites have standardized techniques based on the aforementioned principles for LTE-Advanced systems as part of 4G+/5G deployments.Some of these techniques in LTE-Advanced deployments include carrier aggregation, evolved Multimedia Broadcast/Multicast Services (eMBMS) over LTE Single frequency networks, enhanced Inter-Cell Interference Coordination (eICIC) in LTE heterogeneous (HetNets), Coordinated Multi-point transmission (CoMP) with MIMO OFDMA 2D/3D beamforming for multi-cell self-organized networks (SoN), LTE deployments in unlicensed bands and their co-existence with WiFi, etc. Carrier Aggregation is based on aggregate frequency sub-band carriers of the same/varying bandwidths in the cellular base stations from the licensed band exclusively meant for cellular deployment (like LTE-Advanced Carrier Aggregation), as well as from the unlicensed band where other radio access technologies are also deployed (like License-Assisted Access and LTE-WiFi Aggregation in Unlicensed LTE). LTE-WiFi aggregation, in addition to eICIC HetNets, is also based on network heterogeneity. Network Heterogeneity deals with co-existence of cellular base stations with heterogeneous transmission capabilities or different radio access mechanisms. In HetNets, small cell deployments are used to enhance the coverage and capacity of macro cells. However, since LTE small cells with lower transmission power transmits on the same frequency bands as the macro cells (with higher transmission power), the latter heavily interferes with the former. eICIC focuses on co-existence of LTE small cells with LTE macro cells by appropriately managing their co-channel interference. Video broadcast over LTE single frequency networks is based on transmit diversity, which coordinates multiple LTE base stations to synchronize their redundant data transmissions on the same frequency-time resources and using the same modulation rates across the base stations, which increases the SINR at the users due to constructive combining of signals. CoMP with coordinated beamforming techniques is based on spatial multiplexing, which deals with transmission of independently-encoded data signals on the same frequency-time resources across multiple antennae deployed on the cellular base stations by overcoming interference. Our dissertation broadly discusses spectrum allocation and channel quality issues concerning the above deployments, and provides radio resource management and self-organized network solutions with regards to optimizing pertinent system utility functions. Particularly, our dissertation focuses on a common goal of analyzing the impact of cell-edge users in these network deployments and improving their overall performance, especially in terms of throughput and fairness. Furthermore, our dissertation focuses on meeting the Quality-of-Service (QoS) requirements of the operator in terms of delivering guaranteed bit rates for the subscribed applications, and enhancing the overall Quality-of-Experience (QoE) of users.