Interference Analysis Between Digital Terrestrial Television (DTT) and 4G LTE Mobile Networks in the Digital Dividend Bands

With the introduction of digital terrestrial television (DTT) and the analogue television switch-off, terrestrial broadcast spectrum in the UHF band is being released for mobile communications, in particular for fourth generation (4G) long term evolution (LTE) mobile services. This spectrum is known as digital dividend. An impending problem when deploying 4G LTE mobile networks in the digital dividend bands is that interferences may appear in the adjacent radio frequency channels used for DTT. In this paper, we analyze the adjacent coexistence of DTT and 4G LTE networks in the digital dividend bands at 700 MHz and 800 MHz. A generic framework is adopted such that results can be easily extrapolated to different scenarios and bands. Results are presented as a function of the guard band between technologies, for both LTE uplink and downlink adjacent to the DTT signals, and for fixed outdoor and portable indoor DTT reception. Also, the effect of using anti-LTE filters is studied.This work was supported by the Spectrum Regulator of Colombia ANE (Agencia Nacional del Espectro).Ribadeneira Ramírez, JA.; Martínez, G.; Gómez Barquero, D.; Cardona, N. (2016). Interference Analysis Between Digital Terrestrial Television (DTT) and 4G LTE Mobile Networks in the Digital Dividend Bands. IEEE Transactions on Broadcasting. 62(1):24-34. doi:10.1109/TBC.2015.2492465S243462

PLANIFICACIÓN Y OPTIMIZACIÓN DE REDES DVB-T PARA LA PROVISIÓN DE SERVICIOS LOCALES Y MÓVILES EN COLOMBIA

RESUMEN Actualmente, el estándar dominante a nivel mundial para la transmisión de TV digital Terrestre es DVB-T (Digital Video Broadcasting- Terrestrial). La mayoría de redes desplegadas han sido diseñadas para una alta capacidad de transmisión y en configuración de frecuencia única (SFN por sus siglas en inglés). DVB-T se diseñó para transmisión fija, con una capa física que no presenta la suficiente robustez para prestar servicios en movilidad. Adicionalmente, uno de los problemas de las redes SFN es la transmisión de contenidos locales, ya que todos los transmisores deben emitir el mismo contenido sincronizado en tiempo y frecuencia. En países donde aún no ha sido implementada la red de Televisión Digital Terrestre (TDT) como Colombia, se puede planificar la red haciendo uso de los últimos avances tecnológicos para ofrecer servicios de recepción fija y móvil, definir áreas de contenidos locales o regionales (LSA por sus siglas en inglés) en redes SFN y maximizar el nivel de cobertura en el escenario de despliegue. En este artículo se describen las siguientes soluciones técnicas compatibles con DVB-T para planificar y optimizar las redes TDT y se presentan parte de los resultados obtenidos en la investigación: diversidad de antenas, modulación jerárquica, mecanismos de corrección de errores en capa de aplicación (AL-FEC por sus siglas en inglés), codificación de video escalable SVC, time slicing, componente de transmisión satelital y gap-fillers. Adicionalmente, se describe la metodología de evaluación y validación de cada una de las soluciones propuestas. El artículo aborda temas de investigación que permiten la penetración en nuevos escenarios de recepción y nichos de mercado para la TV digital, y abre la oportunidad de establecer convenios de cooperación internacional entre instituciones colombianas y de países que al día de hoy ya han finalizado con éxito la transición de televisión analógica a digital, como es el caso de España. PALABRAS CLAVES: DVB-T móvil, Modulación jerárquica, Diversidad de antenas, Corrección de errores en capa de aplicación, Áreas de servicio local.  ANALYTICAL SUMMARY Nowadays, the dominant standard for broadcasting Digital Terrestrial Television (DTT) services on the world is DVB-T (Digital Video Broadcasting- Terrestrial). Most of the DVB-T networks deployed have been designed for high capacity transmission and configured in Single Frequency Network (SFN). DVB-T was designed for fixed rooftop reception using a physical layer with low robustness for mobile services. Further, the transmission of Local Services Area (LSA) is one of the disadvantages of SFN networks, because, all transmitters must broadcast the same content synchronized in time and frequency. In countries like Colombia, where the DTT network has not yet deployed is possible to design the future network using the latest technological advances in order to offer fixed and mobile TV services, defining Local Services Areas in SFN network topologies and maximizing the coverage level on the target scenario. This paper describes the follow technical solutions compatible with DVB-T for planning and optimizing the DTT networks and presents some results obtained: antenna diversity, hierarchical modulation, Application Layer Forward Error Correction (AL-FEC), Scalable Video Coding (SVC), time slicing, satellite component and gap-fillers. Additionally, it describes the methodology used to evaluate and validate each of the solutions proposed. The paper addresses issues of research that open news reception scenarios and market niches for digital TV, creating opportunities of international cooperation projects between Columbian institutions and countries that have successfully completed the transition from analog to digital TV, like Spain.  KEYWORDS: Mobile DVB-T, Hierarchical Modulation, Antenna diversity, Application Layer Forward Error Correction, Local Service Area

PLANIFICACIÓN Y OPTIMIZACIÓN DE REDES DVB-T PARA LA PROVISIÓN DE SERVICIOS LOCALES Y MÓVILES EN COLOMBIA

RESUMEN Actualmente, el estándar dominante a nivel mundial para la transmisión de TV digital Terrestre es DVB-T (Digital Video Broadcasting- Terrestrial). La mayoría de redes desplegadas han sido diseñadas para una alta capacidad de transmisión y en configuración de frecuencia única (SFN por sus siglas en inglés). DVB-T se diseñó para transmisión fija, con una capa física que no presenta la suficiente robustez para prestar servicios en movilidad. Adicionalmente, uno de los problemas de las redes SFN es la transmisión de contenidos locales, ya que todos los transmisores deben emitir el mismo contenido sincronizado en tiempo y frecuencia. En países donde aún no ha sido implementada la red de Televisión Digital Terrestre (TDT) como Colombia, se puede planificar la red haciendo uso de los últimos avances tecnológicos para ofrecer servicios de recepción fija y móvil, definir áreas de contenidos locales o regionales (LSA por sus siglas en inglés) en redes SFN y maximizar el nivel de cobertura en el escenario de despliegue. En este artículo se describen las siguientes soluciones técnicas compatibles con DVB-T para planificar y optimizar las redes TDT y se presentan parte de los resultados obtenidos en la investigación: diversidad de antenas, modulación jerárquica, mecanismos de corrección de errores en capa de aplicación (AL-FEC por sus siglas en inglés), codificación de video escalable SVC, time slicing, componente de transmisión satelital y gap-fillers. Adicionalmente, se describe la metodología de evaluación y validación de cada una de las soluciones propuestas. El artículo aborda temas de investigación que permiten la penetración en nuevos escenarios de recepción y nichos de mercado para la TV digital, y abre la oportunidad de establecer convenios de cooperación internacional entre instituciones colombianas y de países que al día de hoy ya han finalizado con éxito la transición de televisión analógica a digital, como es el caso de España. PALABRAS CLAVES: DVB-T móvil, Modulación jerárquica, Diversidad de antenas, Corrección de errores en capa de aplicación, Áreas de servicio local.  ANALYTICAL SUMMARY Nowadays, the dominant standard for broadcasting Digital Terrestrial Television (DTT) services on the world is DVB-T (Digital Video Broadcasting- Terrestrial). Most of the DVB-T networks deployed have been designed for high capacity transmission and configured in Single Frequency Network (SFN). DVB-T was designed for fixed rooftop reception using a physical layer with low robustness for mobile services. Further, the transmission of Local Services Area (LSA) is one of the disadvantages of SFN networks, because, all transmitters must broadcast the same content synchronized in time and frequency. In countries like Colombia, where the DTT network has not yet deployed is possible to design the future network using the latest technological advances in order to offer fixed and mobile TV services, defining Local Services Areas in SFN network topologies and maximizing the coverage level on the target scenario. This paper describes the follow technical solutions compatible with DVB-T for planning and optimizing the DTT networks and presents some results obtained: antenna diversity, hierarchical modulation, Application Layer Forward Error Correction (AL-FEC), Scalable Video Coding (SVC), time slicing, satellite component and gap-fillers. Additionally, it describes the methodology used to evaluate and validate each of the solutions proposed. The paper addresses issues of research that open news reception scenarios and market niches for digital TV, creating opportunities of international cooperation projects between Columbian institutions and countries that have successfully completed the transition from analog to digital TV, like Spain.  KEYWORDS: Mobile DVB-T, Hierarchical Modulation, Antenna diversity, Application Layer Forward Error Correction, Local Service Area

Adaptive planning of 3G/4G systems using Q-analysis or polyhedral dynamics

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Game engines ray-tracing models for indoor channel modeling

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Multiple diffraction shadowing simulation model

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