Video Over LTE: Exploring Efficiency in Distribution

Interest in Long-Term Evolution (LTE) broadcast technology is increasing rapidly. With consumer desire for “Television (TV) Anywhere” at an all-time high, more and more leading mobile operators globally are trialling the LTE Broadcast technology within their networks to start identifying different use cases and scenarios to explore its business potential. Broadcasting is usually efficient if more than one user is receiving from one transmitter. Rooftop reception enables a wide reach from high-power high-tower transmitters, so that broadcasting is efficient for popular TV programs, particularly if transmitters operate in single-frequency network mode. LTE, including LTE Broadcast, is currently designed to operate on low-power low-tower networks. This paper discusses the spectral efficiency and flexibility of LTE Broadcast, which is only efficient when several devices receive the same content stream. Unicast is much more efficient for less popular, so called “long-tail” content. For times when there is only low interest in a certain part of the network, the infrastructure can stop the broadcast and use the resources for unicast content delivery and the spare resources for mobile broadband. Furthermore, the implications of differences in replacement cycles of fixed TV receivers and mobile devices are discussed. A signal adapted to the high radio signal quality of rooftop antennas should be used for the legacy technologies supporting fixed receivers, whereas a signal adapted to the low radio signal quality typical for mobile reception is required. Thus, it is essential to use the most efficient technologies soon after ratification of the standards. Finally, we outline a potential use of existing rooftop antenna installations for LTE modems that can be used for TV distribution and beyond.