Early deployments and trials have already shown productivity and efficiency benefits enabled by private 5G in industrial settings and in some cases demonstrated these could not be achieved through alternatives, such as 4G/LTE or the latest WiFi 6.
They have also exposed the challenges facing operators as they attempt to gain a foothold in the private enterprise 5G space and avoid being cut out of the loop by infrastructure providers going direct to the customer, as Nokia has been actively pursuing in Germany especially. Indeed, German airline Lufthansa recently opened the lid on two deployments that highlighted the challenges faced both by itself in exploiting private 5G effectively for aircraft engineering processes in its hangars, and by its suppliers in addressing the specific requirements.
Most interesting was the fact that Lufthansa Technik, the airline’s aircraft services division, has deployed two private 5G networks side by side at a single site in Hamburg, one telco-provided from Vodafone via a macrocell just outside, and the other installed by Nokia directly across two hangars at the site. These were set up just over a year ago in January 2020 shortly before the Covid-19 pandemic struck, using vertical spectrum in what was claimed at the time to be the first industrial deployment of 5G Standalone (SA) outside Asia. The provider of equipment for the Vodafone network was not stated but it was quite likely Ericsson as a major supplier to the operator there.
Preliminary results of the trials were presented at a private LTE and 5G discussion organized by provider of cellular networks Athonet. There was no smoking gun favoring one network or the other, but there were indications that Vodafone and its infrastructure provider had to adapt their approach quickly to meet the requirements. Lufthansa indicated there were problems with both deployments that were overcome to yield significant benefits in each case. But then Lufthansa insisted on managing both networks itself, leaving both Vodafone and Nokia in subordinate supporting roles.
The roles of the two networks were rather different, illuminating challenges for industrial 5G, particularly latency, speed of transmission and signal degradation, with in practice users accepting performance levels well short of headline rates.
The Nokia network was used to test engine parts remotely with suppliers in their workshops over an ultra-high definition video link, before shipping to the hangars. This incorporates augmented reality (AR) annotation to write over the video and enable the two parties to home in on appropriate fixes or tweaks in real time. The main requirements were therefore high speed, consistent quality and reliability.
Claudius Noack, IT consultant at Lufthansa Industry Solutions, a unit involved in the deployment, indicated it had worked out as the perfect lockdown solution, although its original motivation had been to save time and costs associated with travel and logistics during normal times.
Then the Vodafone setup allows Lufthansa Technik staff to work with higher precision than before on the interior of aircraft fuselages using high-resolution virtual and augmented reality images. So again, low latency and high speed were critical, but in this case with the additional requirement that the network be resilient against degradation of the signal inside aircraft fuselages.
This was therefore the most revealing of the two because it demonstrated what had been unclear, that 5G would work in a very metallic environment with a lot of aluminum alloy to disrupt the signals, as well as fluorescent lighting which was also known to be a source of potentially disruptive magnetic fields. The hull appeared to reduce bit-rate by 5% but the lighting by a further 32%, resulting in around 700Mbps. But the use of beamforming to direct the stream from the antenna to tablets held by technicians boosted bit rate to 1.2Gbps outside the aircraft hull and 800Mbps inside, which was more than adequate.
The conclusion was that private 5G can work in challenging electromagnetic conditions but thorough testing must be done. Another key point was that 5G will not come close to promised headline levels of either latency or throughput in real environments, at least not yet, but still delivers a lot more than any alternative wireless technologies. In the case of latency, 7ms was achieved, not close to the much-touted 1ms, but still leaving plenty of headroom in this case because both use cases required only that it be kept below 100ms.
The main requirement here then was that the latency must be stable and always below that 100Mbps limit, which had led Lufthansa away from WiFi as an option. According to Noack, WiFi connections drop between access points (APs), which, he said, could result not just in video streams stalling at critical moments, but also AGVs (automated guided vehicle) grinding to a halt.
Admittedly that experience was based on WiFi 5, so Noack was naturally asked about the latest WiFi 6. He merely indicated he had seen no evidence yet that would fix the issue of reliable low roaming latency.
The experience has also confirmed that mobile operators can play a key role as advisors even if it says little about whether they can compete with offerings over their existing public infrastructure with the help of network slicing. In this case, although Vodafone came in from a macro cell outside the site, both networks, as well as being managed by Lufthansa, used the company’s own spectrum in the 3.7-3.8 GHz band, which regulator BNetzA has dedicated for leasing by enterprises across the whole country.
Further evidence that operators can and perhaps must participate in collaboration with other enterprise partners rather than as providers of network capacity directly can be found within the European Union’s Horizon 2020 5G Infrastructure Public-Private Partnership (5G-PPP). In one trial installation under this initiative, Ericsson is striking out by deploying a standalone private 5G network without direct operator involvement, at a Ford engine plant in Valencia, Spain.
However, Telefónica is involved by providing access to its 5G-equipped Open Innovation Laboratory (5TONIC) co-creation laboratory in Madrid, which it established with research institution IMDEA Networks. The aim here is to “innovate and experiment” with Industry 4.0 applications.
But Ericsson is providing both radio and core networking technology, which is interesting as unlike Nokia it has been seeking to address private 5G networking opportunities with carrier partners. Here, Ericsson has stated that the 5G pilot network will incorporate edge computing, while experimenting with advanced robotics and AI algorithms to optimize distribution and logistics within factory warehouses.
So here again the operator is taking a more subordinate role in the project, in this case behind the infrastructure provider, albeit in a collaborative effort.