Merging 5G broadcast with unicast is rapidly becoming a reality, with the potential to create cable-free studios or deliver remote event coverage as if it was taking place locally, discovers Andrew Williams.
5G is among the most interesting and powerful budding technologies in broadcast. It offers a novel and practical way to move from unicast to manycast. While case studies of this approach often lead with its use in emergency scenarios, the applications of 5G are truly multi-faceted.
These were explored at a panel discussion at IBC2022, featuring key industry figures working on the development of these very technologies.
They explored how 5G broadcasting can be merged with unicast, the two switching between each other with such smoothness the transition is imperceptible to the viewer. And how 5G can be used to make an almost cable-free studio, the feeds from multiple cameras transmitted wirelessly over 5G.
The latency connection
5G can replace core elements of broadcasting and production. However, one factor stands out to bring these hugely different use cases together. It’s latency.
The low latency and high bandwidth nature of 5G is what makes these projects feasible in the first place. But the onward development of them is still very much tied to cutting latency down.
“Latency is a big deal for production use in a lot of cases,” said the BBC’s Peter Brightwell.
This makes intuitive sense in this case, where 5G is effectively replacing the cables that would usually connect a camera to the rest of the studio. Even today the possible results are highly impressive.
“We worked out we were getting around 150-180 milliseconds of latency, glass-to-glass, which is quite impressive. The bulk of that is down to the encoding and decoding,” said Brightwell’s BBC colleague Ian Wagdin.
“We’re looking at how you can drive that down because once you get below that magical 100ms layer you, you can almost intercut this with wired cameras.”
This does not require a special camera either. Standard broadcast cameras are instead connected to low weight, low bulk circuit board computers. One of these is the 140g Nvidia Jetson Nano, which might be compared to the well-known Raspberry Pi 4, but with greater graphics power.
Cable-free production cameras
The technology has already been used in the field too, which is where the team assessed the latency of this 5G rig.
“In Copenhagen, at the Tour de France, our project partners at TV2 invited us over to do some tests and trials in a real-world event,” said Wagdin. “So what we did was to take a neutral wireless network, a small portable NPN to give us some coverage. We connected two cameras [over 5G].”
For those invested in how technology is shaping the future of production, it is tempting to start imagining studios simply flooded with 5G, sending all data over the 5G IP layer. However, Brightwell suggests a more thoughtful approach:
“Every production is slightly different. There will not be much benefit to using this 5G tech right now in a purpose-built scenario like “Strictly Come Dancing or a football match where you’ve got pre-existing cables in a stadium.”
The power of the 5G is the way “you can treat something remote as if it were local,” Brightwell explained. Hunting down the possible wins is all part of the development of the technology. It also brings about challenges of its own that may not be immediately obvious.
“You start to think about, how do you handle hired cameras, when you need to be able to limit that access to just that period of time?” said Brightwell.
At this point of development, 5G is not going to replace ‘the cable’ wholesale. But the concept has significant potential to streamline the studio pipeline, as Wagdin explained.
“When we use radio cameras for light entertainment and sport, we also have a bunch of other radio signals we attach to the camera,” he said. “We’ve got this bi-directional network now, we can do it all with one radio signal and be much more efficient.”
In these kinds of scenarios, the technology will only be truly successful when it is invisible. Once again, part of this comes down to latency, the additional delay incurred when working wirelessly instead of in a traditional manner.
Blending forms of content distribution technology
Fraunhofer Fokus tests this with its 5G projects aimed at prodding at the question of “how can we combine 5G streaming and broadcast technology,” as project manager Daniel Silhavy explained.
The company’s IBC2022 Show demo showed a feed dynamically shifting from a 5G broadcast to a traditional CDN unicast feed, with no interruption in what the viewer sees. “From the client’s perspective the playback is fluent,” said Silhavy.
This means a phone could stream from a 5G broadcast when in range, then switch to the unicast alternative if the device moves out of range or loses the signal for some other reason. “We have a fallback to the CDN path if the broadcast is not available anymore,” he said.
The interaction between the 5G broadcast and the unicast feed can be far more granular, though, and this is where its application takes on a more commercial bent. Unicast can be used to populate a 5G broadcast feed with adverts, the two elements melded so they become a seamless whole.
“You deliver your main content over broadcast, then do the unicast version on the server side so everyone gets a personalised advertisement,” said Silhavy.
The two-way nature of this interaction, between viewer and provide, is what makes personalisation of embedded adverts not just possible but the obvious route. “What’s really important is we get some kind of feedback from the user equipment, some form of usage report,” said Silhavy.
Personalisation need not stop at advertising either. “What’s also possible if you can offer additional language or subtitles via unicast,” he said. This weaving together of technologies helps to harness the efficiency of 5G broadcast, while addressing some of its core potential shortcomings, making 5G a realistic prospect in a whole further swathe of situations.
Daniel Silhavy, Project Manager at Fraunhofer Fokus, BBC Senior Technology Transfer Manager Ian Wagdin and BBC Lead R&D Engineer Peter Brightwell detailed their respective projects in a session ‘the world of 5G broadcast’ at IBC2022. The panel was chaired by Frederic Gabin, Director of 5G Technology & Standards Strategy at Dolby Labs.