Spectrum requirement for cellular TV distribution in UHF band from urban to rural environment

As the number of TV-channels increase and the number of viewers per channel decreases, Terrestrial Broadcasting is becoming a less attractive way to distribute TV. In addition it does not represent a very efficient use of the UHF band (470-790 MHz). In this paper we discuss an alternative, converged platform for TV and mobile broadband provisioning based on LTE cellular technology and infrastructure, here referred to as CellTV. The key feature of Cell-TV is the ability to switch between a unicast mode for small viewer populations and broadcast over LTE single frequency networks (SFN) for popular content. The main advantage is that the spectrum can flexibly be shared with LTE mobile data services, effectively freeing significant parts of the UHF spectrum for these purposes. Based on a case study of the greater Stockholm area, significant potential for spectrum saving is identified in urban areas where the need for spectrum is the largest. Meanwhile, only limited spectrum savings are observed in rural areas due to the large user populations in each cell and the long inter-site distance. As most of the TV channels are broadcasted in urban areas but unicasted in rural areas, this switch of transmission modes causes considerably high spectrum demand in suburban areas.