Modelling the energy efficiency of microcell base stations

The power consumption of wireless access networks will become a major issue in the coming years. Therefore, it is important to have a realistic idea about the power consumption of each element in those access networks. In this paper, an energy efficiency model for microcell base stations is proposed. Based on this model, the energy efficiency of microcell base stations is compared for various wireless technologies, namely mobile WiMAX, HSPA and LTE. The power consumption of microcell base stations is about 70-77% lower than for macrocell base stations but a macrocell base station is more energy-efficient than a microcell base station for the same bit rates. However, for the considered case and assuming our parameters are correct, a reduction in power consumption can be obtained by using microcell base stations to fill coverage holes

LTE System Performance Simulations

Use of multimedia services, such as streaming of high quality videos on mobile devices is increasing drastically which requires high data rate and bandwidth on mobile devices. Therefore LTE system is introduced by 3GPP which promises higher throughput on mobile devices i.e. 326.4 Mbps in downlink and 86.4 Mbps in uplink. Theoritically LTE system promises high throughput, high bandwidth utilization, low latency, high spectral efficiency, and high peak data rates than all other 3GPP technologies. The main motive behind this research is to analyze the LTE system performance in practical scenarios to estimate the practical system throughput and peak data rates in different situations. LTE system level simulation are performed in this thesis to evaluate the performance in practical scenarios. The simulation are performed with LTE system level simulator to calculate the user and cell thoughput of the LTE network in different practical scenarios such as outdoor, indoor, deep indoor and in car with different network layouts, antenna downtilt angles and MIMO. Simulation results show that the LTE system user and cell thoughput are greatly affected by interference from the neighbouring cells and are different in practical situation than in theory. Results also show that the interference can be reduced by using different network layouts, antenna downtilting and MIMO. Hence high system throughput can be achieved by mitigating the effect of interference from the neighboring cells

LTE System Performance Simulations

Use of multimedia services, such as streaming of high quality videos on mobile devices is increasing drastically which requires high data rate and bandwidth on mobile devices. Therefore LTE system is introduced by 3GPP which promises higher throughput on mobile devices i.e. 326.4 Mbps in downlink and 86.4 Mbps in uplink. Theoritically LTE system promises high throughput, high bandwidth utilization, low latency, high spectral efficiency, and high peak data rates than all other 3GPP technologies. The main motive behind this research is to analyze the LTE system performance in practical scenarios to estimate the practical system throughput and peak data rates in different situations. LTE system level simulation are performed in this thesis to evaluate the performance in practical scenarios. The simulation are performed with LTE system level simulator to calculate the user and cell thoughput of the LTE network in different practical scenarios such as outdoor, indoor, deep indoor and in car with different network layouts, antenna downtilt angles and MIMO. Simulation results show that the LTE system user and cell thoughput are greatly affected by interference from the neighbouring cells and are different in practical situation than in theory. Results also show that the interference can be reduced by using different network layouts, antenna downtilting and MIMO. Hence high system throughput can be achieved by mitigating the effect of interference from the neighboring cells

Dimensioning of LTE Network.

Long Term Evolution (LTE) is 3GPP enhancement to the current cellular system in use. The purpose of developing this system is to keep 3GPP systems competent enough for decades to come. LTE is designed to have wider channels up to 20MHz, with low latency and packet optimized radio access technology. The peak data rate envisaged for LTE is 100 Mbps in downlink and 50 Mbps in the uplink. With OFDM as the radio access technology, LTE has very promising features, like bandwidth scalability and both FDD and TDD duplexing methods. This thesis is related to the dimensioning of LTE radio access networks and the development of tool for dimensioning purpose. Different steps of the dimensioning process are listed and explained. Methods and models for coverage and capacity planning are developed for dimensioning of LTE radio access networks. Special emphasis is laid on radio link budget along with detailed coverage and capacity. The results are fabricated in an easy-to-use tool for dimensioning. The tool is made in Excel to serve the ease of working. Particular importance is given to clarity in the design of dimensioning tool, achieved by dividing the tool into clearly defined sections. Inputs and outputs are placed on separate sheets. The dimensioning tool calculates the number of cells needed to cover a given area with the user-provided parameters. Excel based tool covers all the basic aspects of the dimensioning process for LTE Access Networks

Radio Resource Management Optimization For Next Generation Wireless Networks

The prominent versatility of today’s mobile broadband services and the rapid advancements in the cellular phones industry have led to a tremendous expansion in the wireless market volume. Despite the continuous progress in the radio-access technologies to cope with that expansion, many challenges still remain that need to be addressed by both the research and industrial sectors. One of the many remaining challenges is the efficient allocation and management of wireless network resources when using the latest cellular radio technologies (e.g., 4G). The importance of the problem stems from the scarcity of the wireless spectral resources, the large number of users sharing these resources, the dynamic behavior of generated traffic, and the stochastic nature of wireless channels. These limitations are further tightened as the provider’s commitment to high quality-of-service (QoS) levels especially data rate, delay and delay jitter besides the system’s spectral and energy efficiencies. In this dissertation, we strive to solve this problem by presenting novel cross-layer resource allocation schemes to address the efficient utilization of available resources versus QoS challenges using various optimization techniques. The main objective of this dissertation is to propose a new predictive resource allocation methodology using an agile ray tracing (RT) channel prediction approach. It is divided into two parts. The first part deals with the theoretical and implementational aspects of the ray tracing prediction model, and its validation. In the second part, a novel RT-based scheduling system within the evolving cloud radio access network (C-RAN) architecture is proposed. The impact of the proposed model on addressing the long term evolution (LTE) network limitations is then rigorously investigated in the form of optimization problems. The main contributions of this dissertation encompass the design of several heuristic solutions based on our novel RT-based scheduling model, developed to meet the aforementioned objectives while considering the co-existing limitations in the context of LTE networks. Both analytical and numerical methods are used within this thesis framework. Theoretical results are validated with numerical simulations. The obtained results demonstrate the effectiveness of our proposed solutions to meet the objectives subject to limitations and constraints compared to other published works

Soluções partilhadas para redes de telecomunicações

Mestrado em Engenharia Eletrónica e de TelecomunicaçõesDespite the substantial increase in the percentage of the globe surface covered by mobile communications, there are issues that have hampered the implementation and development of cellular networks in regions where the market and economic power are still under development. Many of these issues are of economic and financial nature. It is curiously a contradictory fact, since mobile communications on several occasions proved to be a great ally for the growth and economic development of this type of regions. Therefore, in situations such as these, where the development or installation of cellular networks is blocked or conditioned by economic and financial factors, the adoption of infrastructure or service sharing methods can facilitate the implementation and expansion of cellular networks in these regions. The work developed in this dissertation seeks to identify and study the most common methods of cellular network sharing. Through the use of a numerical tool, the effects and techno-economic benefits that each sharing method will bring to the operators interested in entering markets with these characteristics will be analyzed.Apesar do crescente aumento da superfície terrestre coberta pelas comunicações móveis, há questões que têm dificultado à implementação e desenvolvimento das redes celulares nas regiões onde o mercado e o poder económico ainda estão em desenvolvimento. Muitas dessas questões são de carácter económico e financeiro. O que se torna, curiosamente, um facto contraditório, uma vez que as comunicações móveis em diversas ocasiões provaram ser um grande aliado para o crescimento e desenvolvimento económico deste tipo de regiões. Portanto para situações como estas, onde o desenvolvimento ou instalação de redes celulares é travado ou condicionado por factores de carácter económico e financeiro, a adopção de métodos de partilha de infraestruturas ou serviços consegue facilitar a implementação e expansão de redes celulares nestas regiões. O trabalho desenvolvido nesta dissertação procura identificar e estudar os métodos mais comum de partilha. Através do uso de uma ferramenta de cálculo, analisam-se também os efeitos e benefícios económicos que cada método de partilha trará para os operadores interessados em entrar em mercados com características aqui consideradas

Dimensioning mobile WiMAX in the access and core network : a case study

Existing broadband wireless technologies such as evolving 3G and WiFi have enjoyed widespread adoption but are far from offering the flexibility in deployment and high data rates. Mobile WiMAX, an emerging broadband wireless technology promises to bring a new experience to mobile broadband services by offering users high data rates and efficient network access techniques. This thesis work provides a technical description of mobile WiMAX and compares its technical capabilities with the existing technologies such as WiFi and 3G. The work continues further on dimensioning mobile WiMAX in the access and core network. In the access network, we determine the number of base stations required to cover a given metropolitan area, explore their configurations, and perform frequency selection. In the core network we dimension the interfaces, and nodes involved. From the study we will show that WiMAX provides the operator with the antenna configurations options of high capacities, large cell coverage area, and a wide selection of QoS classes. The study will also show that the data density requirements of customers, resulting from the capacity analysis are fulfilled by properly dimensioning the elements in the access and core network

Identification of Technologies for Provision of Future Aeronautical Communications

This report describes the process, findings, and recommendations of the second of three phases of the Future Communications Study (FCS) technology investigation conducted by NASA Glenn Research Center and ITT Advanced Engineering & Sciences Division for the Federal Aviation Administration (FAA). The FCS is a collaborative research effort between the FAA and Eurocontrol to address frequency congestion and spectrum depletion for safety critical airground communications. The goal of the technology investigation is to identify technologies that can support the longterm aeronautical mobile communication operating concept. A derived set of evaluation criteria traceable to the operating concept document is presented. An adaptation of the analytical hierarchy process is described and recommended for selecting candidates for detailed evaluation. Evaluations of a subset of technologies brought forward from the prescreening process are provided. Five of those are identified as candidates with the highest potential for continental airspace solutions in L-band (P-34, W-CDMA, LDL, B-VHF, and E-TDMA). Additional technologies are identified as best performers in the unique environments of remote/oceanic airspace in the satellite bands (Inmarsat SBB and a custom satellite solution) and the airport flight domain in C-band (802.16e). Details of the evaluation criteria, channel models, and the technology evaluations are provided in appendixes