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LTE Broadcast: in search of a commercial application

EE is among the operators that have begun tests of LTE Broadcast technology.

EE is among the operators that have begun tests of LTE Broadcast technology.

LTE Broadcast is an impressive technology but it opens up more questions than answers, a major one being what is the commercial application for it? Adrian Pennington reports.

The DVB-H standard once held out a lot of hope for broadcasting live TV to mobile devices, but the technology never took off. To some extent LTE Broadcast (also known as evolved Multimedia Broadcast Service or eMBMS) is similar: a great piece of technology, but one that is still looking for a market.

The critical difference this time around is that where DVB-H depended on a whole new infrastructure for deployment, LTE Broadcast is relatively well integrated with upgrades of mobile infrastructure to 4G. But the big question remains: who is going to pay for it?

Managed service provider Quickplay has no doubts. “The ecosystem is maturing at a rapid space; the network infrastructure and chip manufacturers are aligned around one common standard,” says Jim Nelson, co-founder of Roundbox, which was acquired by Quickplay in March to boost the company’s LTE credentials.

The first use-cases are in-venue where trials during sports events like NFL and European soccer matches continue. Quickplay’s latest trials included one in May, which sent five HD streams over Vodafone’s 4G network during a La Liga match played at Valencia FC’s Mestalla stadium. Huawei video servers, Qualcomm chips, Thomson video decoders and Samsung handsets were other components.

“Where 80,000 people are trying to access video in one spot (whether the same video stream or not) using LTE Broadcast to alleviate the bandwidth strain is natural,” says Nelson. Quickplay sees a subscription model working in this scenario.

Beyond that the company is looking to monetise the network by interfacing Quickplay headends into the LTE network for content providers. Quickplay can provide ingest, encoding, content packaging and apply business rules to push content out to networks provided by Ericsson, Samsung, Alcatel and others.

Applications include push-VoD, where certain sets of VoD assets are cached on the device for later playback. This, says Nelson, would be monetised either as a traditional pay model or ad-supported.

“An operator can push the most common titles or bundles – of sports, lifestyle programming etc – to devices based on user profiles and intelligent algorithms. It will include full DRM with expiry and content protection,” he says.

In enterprise use cases, LTE Broadcast could be sold to large corporates or governments looking to push software updates, notifications, or public safety messages to digital signs, for example. Quickplay also suggests a monetization case in leasing bandwidth to third parties.

Another use case is live linear TV in which small packages of channels – focused on sports, entertainment, lifestyle – might be broadcast for a subscription.

“This is not going to replace the US cable system. LTE doesn’t have that kind of capacity,” says Nelson. “But in developing countries, LTE Broadcast is overtaking the TV infrastructure. You can have eight to ten channels and that becomes the offer to a large number of people.”

Nokia cost analysis

The potential of the technology to replace terrestrial broadcasting standard DVB-T or T2 in Europe has excited many. Nokia has arguably gone the furthest in testing the technology’s fitness for purpose in this regard.

Its Munich trial, ongoing since July 2014 and due to end March 2016, is the first and still the only one to apply the eMBMS technology on the UHF spectrum, using part of the 700MHz band to broadcast over a 200 square km area for national broadcasting. The 700MHz band is the hotly contested spectrum used by DTT in Europe.

“We’ve done cost analysis of deployment of eMBMS, which is a software update of existing base stations, and concluded that it depends on the availability of antennas,” says Helmut Schink, head of telco standards, Nokia Networks. “The business case we have analysed is that the cost to operate an eMBMS network is comparable to the DTT network. Because we can reuse the sites of 2G and 3G deployment we do not need to deploy eMBMS on all sites, but only around a third of sites, which drives cost down. We think this makes LTE Broadcast in urban environments absolutely possible and cost efficient with current technology.”

Nokia believes the chances of eMBMS replacing DVB-T in certain territories is good.

“When you compare both technologies there are certain advantages with eMBMS,” says Schink. “DVB-T is fragmented in Europe and in other parts of the world there’s another standard. LTE Broadcast on the other hand provides a global standard. That makes it immediately attractive to companies outside broadcast, such as automotive manufacturers who do not want to cope with regionally fragmented standards.” [icitspot id=”452982″ template=”box-story”]

In addition, says Volker Held, head of innovation marketing, Nokia Networks, LTE Broadcast provides better spectrum utilisation than the high-tower solution of DVB-T.

“When you operate DVB-T you operate multiple frequencies. One of the big advantages is that we are using a single frequency network for covering a wide area and are proving that to be much more efficient than DVB-T from a cost perspective. LTE for broadcasting is comparable to DVB-T, so we are not adding a more expensive technology. When you add all of these things together the chances of eMBMS replacing DVB-T are good.”

Nokia supports this claim by pointing out that its partner in the trial is research body Institut für Rundfunktechnik (IRT), research body for Germany’s public broadcasters. “We are also talking with the BBC,” says Held. “These two groups are forward-thinking organisations and the BBC in particular has a big impact on the broadcast community. They understand the capability of eMBMS.”

Schink admits, though, that the BBC does not see it is a short-term replacement for DTT in the UK where 10.6 million households receive TV via Freeview. “In other countries the scenario is more attractive. There is 10% DVB-T coverage in Germany, and in other areas it’s below this, plus there are fewer outdoor antennas so base station density needs to be higher,” he says.

Nokia is talking to operators, many of whom recognise the opportunity to use LTE to broadcast content, according to Held. “Not all of them see a requirement to broadcast public service media with full coverage nationwide, but they do recognise use cases for broadcasting content in higher population density metropolitan areas with or at sports events.”

Even when the current project ends the Munich infrastructure is unlikely to be torn down, say Nokia. Meanwhile, the company has embarked on Future-UHF in Finland which is testing supplemental downlink. The main advantage of this technique is that LTE Broadcast could be deployed in areas where there is no DVB usage.

The EBU view

Nokia’s diagnosis sits at odds with several key members of the European broadcasting community. Among them, the EBU, which states categorically that LTE Broadcast is no substitute for DVB-T.

“DTT and LTE are designed and used for different purposes,” explains Darko Ratkaj, senior project manager, technology and innovation, EBU. “DTT is a purpose built platform for a cost-efficient delivery of linear TV services [mainly] to stationary receivers. It provides near-universal coverage and can be received free-to-view which is essential for public service broadcasters. DTT networks are designed for high reliability, robustness, and a sustained QoS delivered to all viewers irrespective of their number or location within the network. DVB-T2 is a state-of -the-art transmission system and rather spectrally efficient.”

LTE Broadcast on the other hand is described by Ratkaj as an operational mode whose “primary purpose is bandwidth optimisation” on a base station for certain types of usage. “eMBMS cannot operate without the unicast LTE network. LTE networks are designed for reception on handheld devices – either stationary, portable, or mobile – but not via fixed roof-top antennas.”

In addition, Ratkaj notes that the coverage of LTE networks does not match that of DTT and that there is no free-to-air reception. “LTE is a general purpose infrastructure that delivers best-effort services. Pre-defined and sustained QoS is an issue. Costs for both the broadcasters and the viewers would need to be comparable to the costs of DTT. We do not know what the costs of a large scale linear TV distribution over LTE eMBMS would be.”

The cost of converting DTT to eMBMS is a contentious issue. At the turn of the year, Farncombe co-authored a project with Plum Consulting on this topic for the EC and concluded that the economics didn’t work.

“DTT is based on fairly powerful transmitters with relatively low density. LTE would require a mobile technology using smaller cell and a higher density network,” explains MD Jean-Marc Racine. “We also looked at the argument for using LTE to reach the last 10% of the population in Europe which can’t be served by DTT.  These are edge cases where most of the time satellite can be used as cover. So I would bet that LTE Broadcast is not going to replace DTT.”

The Mobile Video Alliance (MVA), which was set up by operator EE to examine multicast over LTE and is now run out of the UK’s Digital TV Group, is set to publish a white paper exploring the technology’s potential.

“LTE Broadcast will not replace DVB-T or DVB-T2 and talk of a migration is slightly missing the point,” says DTG Principal IP Engineer, George Robertson. “The DTG sees LTE and DVB-T/T2 as complementary solutions for different audiences, neither of which is a universal solution for both domestic and mobile reception.”

A push technology

For the foreseeable future, it feels that LTE Broadcast will be a push technology for linear content. “Live or recorded, it’s a push scenario with nothing on demand,” says Robertson. “Live events are the obvious application. LTE Broadcast is live, to mobile devices and via a mobile network. It is, therefore, ideal for the likes of sporting events. I think mobile operators will want to wait and see how successful this type of application is before expanding support across the entire network. If the business case in venues and live events works, then we will see more applications.”

Unsurprisingly, given that it is a co-chair of the MVA, EE agrees with this view. It remains a cheerleader for LTE Broadcast, but has reigned in its ambitions over the last few months, perhaps while BT’s £12.5 billion acquisition of EE goes through.

“The MVA are not discussing [LTE Broadcast] as a DTT replacement but as a way of improving performance and efficiencies of delivering live linear TV, predominantly. On top of that we have all the other services [like mass software updates],” says Matt Stagg, EE principal strategist. EE itself is “actively steering away from that and saying let’s focus on where we need this technology now,” he says. “In the future, who knows?”

EE plans a limited live rollout for LTE Broadcast toward the end of 2016. “We’re not saying it’s a commercial launch but we will start to put capacity on the network for certain events where it provides benefits,” says Stagg.

While Cisco predicts that 72% of mobile traffic will be video by 2020, “we are looking at 75% by 2019,” says Stagg. For that reason EE views 4G as a media distribution network, with LTE Broadcast augmenting an operator’s ability to maximise resources.

“The biggest fundamental shift we will see in the next decade for mobile distribution of TV is LTE Broadcast,” says Stagg. “EE’s vision for LTE Broadcast is that it will be better than TV.” [icitspot id=”452962″ template=”box-story”]

Stagg led the team that delivered the UK’s first engineering proof of concept at the 2014 Commonwealth Games (partnered with the BBC, Qualcomm and others), and followed that up with a trial at this year’s FA Cup Final at Wembley to prove how it could combine the efficiency of broadcast with the functionality of unicast. “It’s the next iteration of red button,” says Stagg.

LTE Broadcast is still in test mode and could be further developed to become capable of delivering linear TV on a large scale. However, technical capabilities alone would not make LTE Broadcast a viable TV platform, according to the EBU. “LTE coverage would need to match or exceed that of DTT,  Free-to-view reception would need to be possible, and LTE Broadcast would need to be spectrally at least as efficient as DTT,” says Ratkaj.

DTT replacement

Legacy DTT receivers in homes would need to be replaced by the (currently non-existent) LTE Broadcast receivers which could take many years, he points out. “We are not aware of any notable efforts to address these issues.”

The EBU acknowledges that the technology does have a certain appeal to operators because of its global standard with which they may be able to reach the whole range of receiving devices. At the same time, the body highlights a major concern that replacing DTT with LTE would “substantially increase the distribution costs for broadcasters” and would “strengthen the gatekeeping position” of mobile operators.

Quickplay reiterates that LTE Broadcast can compete in countries saturated with DVB-T by providing a small number of niche packaged channels as a complement.

“Operators will have the ability to reach customers on mobile – on trains and buses, for example – and enhance the video experience.”

The EBU asks further questions. Who would finance such a transition? Mobile operators, content and services providers, equipment vendors, governments? What would be their incentives? “It is also unclear [what] would be the benefits of such a migration to the viewers,” Ratkaj adds.

Looking around the corner, new business models might possibly drive LTE Broadcast network build-out and deliver the needed technical and cost-efficiency for wide-scale DTT replacement. “There could be an industry-wide consensus that this is the way to go,” says Ratkaj. “Political decisions on spectrum allocation could lead to the decline of DTT and so could a shift of the audience onto other platforms like satellite, cable, IPTV for linear TV.”

Other drivers influencing a possible shift from DTT to LTE include a major shift from linear to on-demand viewing – abandoning the large TV screen in favour of personal mobile devices. Arguments against the likelihood of this happening are many. “There is no viable business model to sustain the whole value chain,” says Ratkaj. “The perceived benefits of LTE are insufficient to justify investment in the technical developments, network rollout, and the transition.”

Politically, the decision to maintain DTT, for example to achieve certain competition or audiovisual policy objectives, remain strong.

Ratkaj holds out the possibility of LTE Broadcast being decoupled from the current mobile operator business model and deployed as a standalone DTT network. “This is not possible with the current LTE eMBMS but a future incarnation might allow it,” he says.

Operators are in a phase of understanding the business opportunities for the technology. It is possible that many will combine LTE Broadcast with unicast VoD and with fixed TV distribution.

As mobile and fixed line providers are coming together in quad platforms as evidenced by the EE/BT deal, LTE could be used as a product differentiator.

“eMBMS doesn’t create value in itself but as part of a quad play bundle to provide quality video over mobile, it could be an interesting product differentiator,” says Racine. “That doesn’t mean consumer’s will pay extra for it, but it’s an interesting angle for mobile operators upgrading their network.”

Racine thinks LTE Broadcast is a technology that has come too late to the party. DTT may eventually be replaced by IP video delivery, he says, but not through the mobile network – through WiFi access.

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