With increasing number of TV channels and growing need for on-demand services, the traditional digital terrestrial television (DTT) is becoming a less attractive way of distributing TV contents. As an alternative, we discuss a converged platform in UHF band for TV and mobile broadband provisioning based on LTE cellular technology and infrastructure, here referred to as Cell TV. The requirement for Cell TV is to provide a seamless TV coverage from urban to rural environments and to minimize the spectrum requirement so that the leftover can be used for mobile services. We formulate an optimal spectrum allocation problem for Cell TV to distribute different TV channels with different transmission modes.
Each TV channel is delivered via either uni cast links or broadcast over single frequency networks (SFNs) of different modulation orders according to the location-dependent viewing demand and cellular infrastructure availability. Based on a case study of the Greater Stockholm region, we identify that Cell TV requires only a small portion of the UHF band to deliver the TV contents in urban areas, thus releasing a significant amount of spectrum for mobile broadband services. Meanwhile, the spectrum requirement for Cell TV is considerably higher in suburban and rural areas due to the transitions of transmission modes. We further generalize these findings to provide a guiding principle for Cell TV deployment in mixed environments and also to demonstrate the flexibility advantage of Cell TV in adapting to the growing diversity of TV contents.