On “new” 5G antennas that have been in place for years

Mobile telecommunications was and is a topic full of contradictions. Today, almost 100 percent of the Swiss population uses mobile telecommunications, yet there are still many who have reservations about mobile phone signals and voice their criticisms. Following on from the previous mobile phone generations, 5G has reignited this debate – one that is often conducted with high emotion and arguments that are not technically sustainable.

The facts: 5G is an improvement on 4G. It involves far more than just new antennas – this is often forgotten in the discussion. After all, a network consists of many elements. The antennas – or "radio access", to use the technical term – are just one part of it. Yet even antennas differ from one another, as they use various frequencies between 700 and 3600 Megahertz. The millimetre waves with frequencies from 26 Gigahertz (26000 Megahertz), which are often mentioned by those opposed to 5G, are not currently authorised in Switzerland for use in mobile telecommunications.

The physics: the higher the frequency, the more data can be transferred, naturally. This is, however, at the expense of range. At lower frequencies, even though less data is transferred per time unit, it extends or "travels” much further instead: across the regions, in basements, garages or inside well insulated houses.

Progress in rapid succession

The mobile phone network is further developed and improved in “generations” – that’s what the G stands for. From 2G to 3G, from 3G to 4G, and so on. The introduction of 5G is therefore nothing more than the next stage of development. Each generation has been better than the last and each generation has offered more possible applications. 2G mainly supported telephony, 3G made mobile broadband Internet possible for the first time and 4G brought the higher bandwidth that now forms the basis for all the applications that we now use every day.

A good network is always a combination of different specifications, a system performance. Today, 96 percent of the Swiss population already receives a 5G signal – even though there are only comparatively few specific 5G antennas (known as adaptive antennas). This is possible because one manifestation of 5G (we call it 5G or 5G-wide) uses existing antennas. These were previously used for 4G or 3G.

We often hear 3G or 4G antennas being mentioned in this context. However, this is technically incorrect. That's because an antenna is not built for a generation, but for a specific frequency. Just as a bottle is merely a container for a liquid, regardless of whether the liquid it contains is water, wine, beer or a sugary drink.

Gradual expansion

The use of existing antennas therefore explains the high coverage figure of 96 percent. With 5G, the existing antennas transmit even more efficiently. State-of-the-art 5G software already uses the spectrum somewhat more sparingly, saves energy and responds more quickly. To use another metaphor: it’s like a PC running on a newer version of the operating system.

And, as with the PC, it is also the case that new hardware is needed in order to use all the functions. That’s where 5G+ comes in. It uses the slightly higher frequencies and more advanced, adaptive antennas. Instead of covering entire sectors, they target the devices in use at the moment. The existing antennas are a bit like a floodlight, which lights up the night sky over an unnecessarily large area, while the new antennas illuminate only the exact places where light is actually needed. It is only this combination of factors that allows all the advantages of 5G to be used, such as higher bandwidths, shorter response times, guaranteed network resources and very high energy savings.

In Switzerland, there is a further, special aspect involved here. In places of sensitive use – where we spend more of our time, like in an apartment or at the workplace – the output must be greatly reduced. Let's return to the example of the bottle: you're only allowed to fill it with a hundred millilitres, even though it could hold a whole litre. In Switzerland, only one tenth of the imissions in this case may be caused by an antenna. This is due to the Swiss precautionary principle.

In border towns, therefore, an antenna on Swiss soil may use one tenth of the output. However, if it is on land belonging to the neighbouring country, the foreign telecoms providers are permitted to transmit with ten times more output, even if the antenna is only a few hundred metres away. This also explains why, in border regions, the devices sometime switch to the foreign network, even if the user is in Switzerland: it's because the foreign network’s signal is stronger.

The country needs new antennas

Because of these very rigorous Swiss requirements, the majority of antenna sites in this country no longer have power reserves. New antennas must therefore be developed and built, which is why we need new antenna sites.

Development is stagnating, however, because building applications are suspended or not processed, or because cantons have imposed unlawful moratoria. This is even blocking the expansion of 4G, too. In 2019, our customers’ data consumption increased six times faster than we were able to expand capacity. Ultimately, mobile telecommunications is physics: a certain quantity of data can be transmitted over a certain frequency. A small part of this can be optimised, for example by using fewer resources for the control instead of the actual content.

If the demand increases significantly, however, the only thing that helps is additional capacity in the form of new antennas. Returning to the bottle analogy, this means that if all the guests are thirsty at the same time, the host must either increase the number of bottles, or obtain the licence that allows him to fill the bottles with more than 100 millilitres. Switzerland has chosen the first option.