Nokia Networks is pioneering the technology needed to efficiently use LTE for nationwide TV broadcasting. The company is working with a range of partners in the world’s first field trial of wide-area TV broadcasting using a single LTE frequency within UHF spectrum. In a Single Frequency Network (SFN) all base stations use exactly the same frequency to transmit TV content, which maximizes the number of simultaneous TV channels broadcast over a large geographical area in a given amount of spectrum.
LTE Broadcast technology promises new revenue sources for operators by distributing TV over existing mobile broadband infrastructure. Subscribers would be able to watch TV on their devices without eating into their mobile data plan and independent of network load. LTE Broadcast allows for a free-to-air or pay-TV service that can be received by anybody with a suitable device, similar to traditional TV broadcasting. Broadcasters and content providers could extend their reach to mobile users and open the door for a multitude of interactive services.
“Today, when watching videos over a mobile network, the content is individually streamed to each user. With LTE Broadcast the same signal is received by many users at the same time, resulting in more efficient capacity and spectrum use,” explains Hossein Moiin, chief technology officer, Nokia Networks. “Spectrum doesn’t need to be dedicated to either broadcast or broadband, but can be used flexibly for both according to users’ needs. We believe that LTE Broadcast is a technology well suited to distribute TV and broadcast services and will help us expand the benefits of mobile internet to everyone while evolving the TV viewing experience.”
Current LTE Broadcast applications focus on delivering media content to contained locations, such as stadiums and concert halls, over limited periods of time. The Munich trial is the first to apply the technology on UHF spectrum, using part of the 700 MHz band to broadcast over a 200 km2 area. To maximize the efficiency of the LTE Broadcast, the SFN has been optimized for tighter synchronization of neighbor cells to increase interference robustness. The trial aims to show that LTE could be used to complement and in the long run, even provide another option to regional digital TV distribution standards, such as DVB-T in Europe.
The trial, which began transmissions in early July in Munich, Germany, uses evolved Multimedia Broadcast/Multicast Service (eMBMS) software running in Nokia Flexi Multiradio 10 Base Stations, which are deployed widely in many LTE networks worldwide. The Nokia LTE equipment is deployed at four sites of the Bavarian broadcast company, Bayerischer Rundfunk, in Northern Munich. The sites are connected by a high performance optical transport network.