Analysis of femtocell for better reliability and high throughput

Abstract: An unrelenting need for mobile broadband data has become the norm for end users. Mobile operators are now faced with a challenge to deliver higher data rates thus has prompted developments for new innovations in mobile technology to satisfy this data hungry generation. Poor indoor building penetration have been a major stumbling block in achieving higher data rates as good signal strength of better quality influences higher data rates. Methods to solve indoor penetration problems such as cranking up power on existing base stations can be an alternate but this can potentially introduce high interference to the system and effectively decrease system capacity. Like in any other wireless communication environment, having a transmitter and receiver closer to each other will potentially increase signal strength thus effectively increasing signal quality and potentially higher data rates. This inevitably means more base stations need to be installed to improve coverage. This idea is not feasible ! in practice based on financial constraints using traditional macro and micro sites thus the emergence of FemtoCell seems to be a feasible endeavour. A FemtoCell BS is a self-installed low powered base station connected to the mobile operator via backhaul using IP connection. This device brings a lot of benefits such as Opex savings, increased spectral efficiency, improved battery life and higher data rates for customers resulting from increased signal Strength. In this paper an overview of advancement of cellular networks from legacy standards 2G to 4G-LTE/LTE-A and benefits/challenges of FemtoCell are analysed

A Planning and Optimization Framework for Hybrid Ultra-Dense Network Topologies

The deployment of small cells has been a critical upgrade in Fourth Generation (4G) mobile networks as they provide macrocell traffic offloading gains, improved spectrum reuse and reduce coverage holes. The need for small cells will be even more critical in Fifth Generation (5G) networks due to the introduction of higher spectrum bands, which necessitate denser network deployments to support larger traffic volumes per unit area. A network densification scenario envisioned for evolved fourth and fifth generation networks is the deployment of Ultra-Dense Networks (UDNs) with small cell site densities exceeding 90 sites/km2 (or inter-site distances of less than 112 m). The careful planning and optimization of ultra-dense networks topologies have been known to significantly improve the achievable performance compared to completely random (unplanned) ultra-dense network deployments by various third-part stakeholders (e.g. home owners). However, these well-planned and optimized ultra-dense network deployments are difficult to realize in practice due to various constraints, such as limited or no access to preferred optimum small cell site locations in a given service area. The hybrid ultra-dense network topologies provide an interesting trade-off, whereby, an ultra-dense network may constitute a combination of operator optimized small cell deployments that are complemented by random small cell deployments by third-parties. In this study, an ultra-dense network multiobjective optimization framework and post-deployment power optimization approach are developed for realization and performance comparison of random, optimized and hybrid ultra-dense network topologies in a realistic urban case study area. The results of the case study demonstrate how simple transmit power optimization enable hybrid ultra-dense network topologies to achieve performance almost comparable to optimized topologies whilst also providing the convenience benefits of random small cell deployments

THROUGHPUT IMPROVEMENT AND COMPARATIVE PERFORMANCE ANALYSIS OF INTEGRATED NETWORKS

The demand for high-speed communication continue to increase significantly. Industry forecasts have shown that future data services would contribute to rapid growth in data traffic, with most of this traffic primarily indoors and at hotspots locations. Thus, the deployment and integration of small cell base stations (SCBSs) with Wireless Local Area Network (WLAN) or Wi-Fi is viewed as a critical solution to offload traffic, maximize coverage and boost future wireless systems capacity. This thesis reviews the existing network of WLAN, Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX). Tight and Loosely coupled integration of these networks is studied. More specifically, the introduction of small cell (SC) in loosely coupled Wi-Fi /WiMAX and Wi-Fi/LTE are proposed. These designs are tested in real-time user experience applications consisting of video conferencing, hypertext transfer protocol (HTTP) and email using industrial simulation software, Riverbed Modeler 18.7. Quality of service parameters was used to analyze these networks. It was found that the throughput of loosely coupled Wi-Fi/WiMAX network can be optimized by small cell. The loosely coupled architecture of Wi-Fi/WiMAX small cell outperforms that of Wi-Fi/LTE small cell. The loosely coupled independently deployed network of Wi-Fi/LTE small cell performs better than the Wi-Fi network. The Wi-Fi/LTE small cell network achieved a substantial rise in downlink throughput in a network consisting of only video conferencing subscriber station

Models and optimisation methods for interference coordination in self-organising cellular networks

A thesis submitted for the degree of Doctor of PhilosophyWe are at that moment of network evolution when we have realised that our telecommunication systems should mimic features of human kind, e.g., the ability to understand the medium and take advantage of its changes. Looking towards the future, the mobile industry envisions the use of fully automatised cells able to self-organise all their parameters and procedures. A fully self-organised network is the one that is able to avoid human involvement and react to the fluctuations of network, traffic and channel through the automatic/autonomous nature of its functioning. Nowadays, the mobile community is far from this fully self-organised kind of network, but they are taken the first steps to achieve this target in the near future. This thesis hopes to contribute to the automatisation of cellular networks, providing models and tools to understand the behaviour of these networks, and algorithms and optimisation approaches to enhance their performance. This work focuses on the next generation of cellular networks, in more detail, in the DownLink (DL) of Orthogonal Frequency Division Multiple Access (OFDMA) based networks. Within this type of cellular system, attention is paid to interference mitigation in self-organising macrocell scenarios and femtocell deployments. Moreover, this thesis investigates the interference issues that arise when these two cell types are jointly deployed, complementing each other in what is currently known as a two-tier network. This thesis also provides new practical approaches to the inter-cell interference problem in both macro cell and femtocell OFDMA systems as well as in two-tier networks by means of the design of a novel framework and the use of mathematical optimisation. Special attention is paid to the formulation of optimisation problems and the development of well-performing solving methods (accurate and fast)

Quantifying Potential Energy Efficiency Gain in Green Cellular Wireless Networks

Conventional cellular wireless networks were designed with the purpose of providing high throughput for the user and high capacity for the service provider, without any provisions of energy efficiency. As a result, these networks have an enormous Carbon footprint. In this paper, we describe the sources of the inefficiencies in such networks. First we present results of the studies on how much Carbon footprint such networks generate. We also discuss how much more mobile traffic is expected to increase so that this Carbon footprint will even increase tremendously more. We then discuss specific sources of inefficiency and potential sources of improvement at the physical layer as well as at higher layers of the communication protocol hierarchy. In particular, considering that most of the energy inefficiency in cellular wireless networks is at the base stations, we discuss multi-tier networks and point to the potential of exploiting mobility patterns in order to use base station energy judiciously. We then investigate potential methods to reduce this inefficiency and quantify their individual contributions. By a consideration of the combination of all potential gains, we conclude that an improvement in energy consumption in cellular wireless networks by two orders of magnitude, or even more, is possible.Comment: arXiv admin note: text overlap with arXiv:1210.843

LTE-Advanced radio access enhancements: A survey

Long Term Evolution Advanced (LTE-Advanced) is the next step in LTE evolution and allows operators to improve network performance and service capabilities through smooth deployment of new techniques and technologies. LTE-Advanced uses some new features on top of the existing LTE standards to provide better user experience and higher throughputs. Some of the most significant features introduced in LTE-Advanced are carrier aggregation, enhancements in heterogeneous networks, coordinated multipoint transmission and reception, enhanced multiple input multiple output usage and deployment of relay nodes in the radio network. Mentioned features are mainly aimed to enhance the radio access part of the cellular networks. This survey article presents an overview of the key radio access features and functionalities of the LTE-Advanced radio access network, supported by the simulation results. We also provide a detailed review of the literature together with a very rich list of the references for each of the features. An LTE-Advanced roadmap and the latest updates and trends in LTE markets are also presented