On the potential of TVWS spectrum to enable a low cost middle mile network infrastructure

The attractiveness of TV white space (TVWS) spectrum for last mile access in rural and developing regions has been recognized before. In this paper, we complement this existing work and draw attention to the potential of TVWS spectrum for enabling low cost middle mile connectivity to the Internet backbone. In particular, we examine the amount and nature of TVWS spectrum available towards this end, considering a representative rural setting in the UK, TV transmitter locations and their configuration, terrain information and antenna type. We introduce a new notion of receiver side usable spectrum that differs from the commonly considered available spectrum at transmitter side obtained from consulting a geolocation database. We find that cumulative interference from multiple nearby TV transmitters can severely reduce the amount of usable TVWS spectrum and also heavily fragments it. However, the use of directional antennas, as would be the case for TVWS backhaul links, negates this effect and suggests the possibility of high speed TVWS backhaul links via spectrum aggregation.