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MASTER THESIS TITLE: Planning optimization software tool for DVB-T and DVB-T2 MASTER DEGREE: Master in Science in Telecommunication Engineering & Management AUTHORS: María Lema Rosas, Evelyn Torras López DIRECTORS: Silvia Ruiz Boqué, Mario García Lozano DATE: June 25 th 2010 TIitle: Planning optimization software tool for DVB-T and DVB-T2 Authors: María Lema Rosas, Evelyn Torras López Directors: Silvia Ruiz Boqué, Mario García Lozano Date: June 25 th 2010 Overview Nowadays the implementation of the Digital Terrestrial Television network is an actual fact in the Spanish territory. Its development is crucial for the digital transition in those countries which mainly depend on terrestrial networks for the reception of multimedia contents. With the aim of giving to the users a high quality signal but with the minimum cost for the operator, it arises the necessity of an optimization of the transmission network. In this way, there are variables that can be modified to obtain this goal, some of them are uncontrollable by the operators and the others are susceptible of optimization. In this last group, it can be found the static internal delays of the transmitters which are of special interest because changes can be done with cost zero. The main objective of this project is the design and implementation of a planning optimization software tool that adjusts the internal static delay in transmitters of a digital broadcasting network. The final objective is to minimize the self-interfered areas and obtain the correspondent increase in coverage. The planning optimization software tool makes use of a metaheuristic algorithm and can obtain different layers of study with its corresponding results. This report describes the problems raised by the current network, the algorithm adapted to the needs of the network to optimize, the implementation of the simulation platform as well as its subsequent validation stage, including several graphical results that allow the evaluation of the improvements introduced over the realistic scenario tested. Finally it has to be mentioned that this work has been performed within the context of the FURIA project, which is a strategic research project funded by the Spanish Ministry of Industry, Tourism and Commerce. Título: Planning optimization software tool for DVB-T and DVB-T2 Autores: María Lema Rosas, Evelyn Torras López Directores: Silvia Ruiz Boqué, Mario García Lozano Fecha: 25 de junio de 2010 Resumen Hoy en día la implementación de una red de Televisión Digital Terrestre es una realidad en España y su desarrollo es crucial para la transición digital para aquellos países en los que la recepción de contenido multimedia depende exclusivamente de las redes terrestres. Con el objetivo de dar al usuario una gran calidad de señal pero con un coste económico y reducido para las operadoras es necesaria la optimización de la res de transmisión. En este sentido, existen parámetros de red configurables para conseguir este objetivo, algunos de ellos son incontrolables para las operadoras, en cambio otros son susceptibles a la optimización. En este último grupo, se encuentran los retardos estáticos internos de los transmisores que son de especial interés debido a que se pueden modificar a coste cero. EL principal objetivo del proyecto es el diseño y la implementación de una herramienta software para la planificación óptima de redes que ajusta el parámetro de los retardos estáticos de los transmisores en redes de difusión digital de contenidos con la intención de minimizar las zonas de auto-interferencia y con el correspondiente incremento de cobertura de red. La herramienta software para la planificación hace uso de un algoritmo metaurístico y puede obtener diferentes capas de estudio con sus correspondientes resultados. La memoria describe los problemas planteados por la red actual, el algoritmo utilizado y como se ha adaptado a las necesidades de la red a optimizar, la implementación de la plataforma de simulación así como su etapa de validación, incluyendo gran cantidad de resultados gráficos que permiten la evaluación de las mejoras introducidas en la red realística testeada. Finalmente se ha de mencionar que el presente trabajo ha sido realizado en el contexto del proyecto FURIA, el cual es un proyecto de búsqueda estratégica fundado por el ministerio de Industria, Turismo y comercio de España. INDEX INTRODUCTION ............................................................................................................ 1 CHAPTER 1. INTRODUCTION TO DVB-T ................................................................. 3 1.1 Changing to a digital mode ............................................................................... 3 1.2 Digital television around the world .................................................................... 3 1.3 DVB-T2 physical layer overview ....................................................................... 4 1.3.1 Basic principle ........................................................................................... 5 1.3.2 Time domain physical layer considerations .............................................. 6 1.4 Radio planning of DVB-T systems ................................................................... 7 1.4.1 Coverage computation .............................................................................. 8 1.4.2 Interferences and their impact on coverage .............................................. 9 1.4.3 Solutions to improve coverage area ........................................................ 10 CHAPTER 2. DESIGN OF AN ALGORITHM TO MAXIMIZE COVERAGE ............... 11 2.1 Problem description ........................................................................................ 11 2.2 Metaheuristic solution ..................................................................................... 12 2.3 Introduction to Simulated Annealing ............................................................... 13 2.3.1 Description of the algorithm .................................................................... 13 2.4 Simulated annealing parameters .................................................................... 15 2.4.1 Temperature ............................................................................................ 15 2.4.2 Number of iterations ................................................................................ 16 2.4.3 Conditions of convergence ...................................................................... 16 2.4.4 Definition of the cost function .................................................................. 16 2.5 Implementation issues .................................................................................... 18 2.5.1 Study of the temperature reduction coefficient ........................................ 18 2.5.2 Maximum delay value delimitation .......................................................... 20 2.5.3 Study of the equilibrium condition ........................................................... 22 CHAPTER 3. SIMULATION PLATFORM DEVELOPMENT ...................................... 25 3.1 Required software tools .................................................................................. 25 3.1.1 Sirenet ..................................................................................................... 25 3.1.2 Microsoft Visual Studio 2008 ................................................................... 25 3.1.3 MATLAB .................................................................................................. 26 3.1.4 Google Earth ........................................................................................... 26 3.2 Simulator structure ......................................................................................... 27 3.2.1 Main program .......................................................................................... 28 3.2.2 Scenario .................................................................................................. 28 3.2.3 Algorithm ................................................................................................. 30 3.2.4 Graphical User Interface ......................................................................... 30 3.3 Code optimization ........................................................................................... 34 CHAPTER 4. RESULTS: OPTIMIZATION OF REALISTICS SCENARIOS .............. 35 4.1 Definition of the scenarios .................................................................................. 35 4.1.1 Tarragona scenario ................................................................................. 35 4.1.2 Lleida scenario ........................................................................................ 36 4.1.3 Barcelona scenario ................................................................................. 37 4.2 Results for geographical optimization ............................................................ 38 4.2.1 Tarragona ................................................................................................ 40 4.2.2 Lleida ....................................................................................................... 41 4.2.3 Barcelona ................................................................................................ 42 4.3 Optimizing population density ........................................................................ 43 4.3.1 Population distribution ............................................................................