Gigabit on hockey. See how the mobile network at the O2 Arena was upgraded ahead of the World Cup

The sports and cultural hall O2 arena has been operating for twenty years. It was opened in 2004 under the name Sazka Arena. In it, you can find several historical phenomena relevant to their time, for example Hušák’s bafunářská office. Nevertheless, the arena is continuously being modernized. Now, for some time, as part of the upcoming world hockey championship, it will be renamed Praha Aréna. The event also includes a significant strengthening of the mobile network.

Places where a large number of people gather at the same time are often problematic for mobile communication. Surrounding transmitters become overwhelmed, which usually means “clogged” data. For impact events, this is often solved by additional transport transmitters. In the case of permanent buildings, such as sports complexes, it is always up to the operator whether to agree with the operators to strengthen the infrastructure.

A good signal can be thought of in a business sense. Thanks to it, additional services can be offered. It also represents good marketing. Visitors can use actionable data to send statuses, stories, tiktoks and other viral attention-generating content.

In the Czech Republic, the best equipped stadium in this respect is the Eden Arena, where Slavia Prague plays. But only in part – while CETIN (and thanks to that O2) has a strengthened infrastructure there, T-Mobile customers often have to decide whether a WhatsApp message will be sent to them at all during a full match (less than twenty thousand people).

Modernization of the O2 arena

The O2 arena has a similar capacity to Eden. During concerts and cultural events, it can accommodate up to 20,000 people, for hockey it is less than 17,500. CETIN has strengthened the mobile infrastructure there, which visitors to the first match of the Czech national team against Finland will be able to test.

Lupa had the opportunity to look at the infrastructure. A challenging experience for those who don’t like heights, the mobile equipment is located on a structure under the roof above the ice surface and stands.

14 so-called nests with telecommunications technology are now installed in the hall of the O2 arena. Each nest has 28 antennas with LTE 2.6 GHz TDD, LTE 2.6 GHz FDE and LTE 3.7 GHz frequencies. In addition, there are 42 additional antennas for the frequencies 800, 900, 1800 and 2100 MHz. In total, there are 70 antennas per nest.

CETIN used technologies from Ericsson for the modernization. On LTE 2.6 GHz FDD it was model E 4415, on LTE 2.6 GHz TDD model AIR 3219 and on LTE 3.7 GHz it was model AIR 3268.

Each nest uses a 175 MHz band when adding blocks. The other six sectors for low-band and mid-band have available blocks of 16 and 20 MHz. And outside the premises of the hall there are another 85 indoor antennas within the arena.

What CETIN’s mobile infrastructure looks like in the O2 arena:

The measured test speed during the inspection fluctuated around 900 Mb/s for download and 190 Mb/s for upload. The record was 942 Mb/s and 196 Mb/s.

Within the arena, 730 meters of optical cables and 600 meters of power cables for the equipment are laid out. The O2 arena is connected by one optical route of CETIN. A second independent route is currently being built, the supplier will be the same.

The highest antennas are at 24 meters, there are twenty pieces in total. The other eight pieces are at a height of 22 meters.

The most challenging thing about upgrading the transmitters was finding time slots when technicians and climbers could run into the arena, because there are always events going on in the area. The climbers worked 320 hours during the event and the assembly workers another 440 hours.

Workers had to place over 900 kilograms in technology. In addition, it was necessary to install 840 kilograms of steel structures at a height of 24 meters. Everything was transported by elevators to a certain height, then manual work had to come. During the upgrade, DC cables were stretched, new optics were installed, FTTA and DC boxes were installed, and a baseband unit was installed. Higher units of millions of crowns went into technology alone.

Also check out the transmitter at the Archbishopric of Prague:

What does the T-Mobile transmitter look like at the church on Náměstí Miru in Prague: