Understanding Switzerland’s super fast 4G Download Speeds with operators’ use of spectrum

When it comes to great mobile network experience, Switzerland holds a strong position among the global leaders. In our recent national report we analyzed the network experience of the country’s three main operators Salt, Sunrise and Swisscom and found that our users on all three networks experienced 4G Download Speeds over 30 Mbps. But what are these operators doing to differentiate themselves in terms of fast speeds?

To understand this, Opensignal looked at the spectrum holdings of each of the three networks. Our data shows there is a strong correlation between the type of 4G spectrum used and the download speeds experienced on these networks. We observed that a higher percentage of our users experienced faster 4G download speeds on those networks that have a greater percentage of cells transmitting data on higher frequency bands.

Analyzing the distribution of our users’ average 4G Download Speeds, we found less than 20% of users experienced the lowest speeds (up to 10 Mbps) on all three networks, with the least on Swisscom (15%), closely followed by Salt (16%), and the most on Sunrise’s (19%). On the other hand, we found 70% of users enjoyed speeds above 20 Mbps on Swisscom’s network ­with over a third of users experiencing average speeds above 50 Mbps. Salt and Sunrise were close to the leader with 65% and 63% of users respectively enjoying 4G Download Speeds faster than 20 Mbps. But Salt and Sunrise had a higher concentration between 20 Mbps and 50 Mbps, with 40% and 37% users on each network respectively at least 3% more than Swisscom.

To explain the high average 4G Download Speeds in Switzerland, we took a closer look at  the spectrum holdings of each of these operators, as they play a key role in the quality of network experience. Low-band spectrum forms a strong base for a network as those frequencies propagate longer distances with improved penetration through obstacles such as buildings, making them ideal for both rural and suburban areas. Mid-and high-band spectrum, on the other hand, provides capacity that helps to deal with high demand and congestion, especially in densely populated urban centres.

There are multiple ways to look at frequency distributions. One is to consider the proportion of data per cell served over each frequency, or the whole network per frequency, or even the proportion of time users spent on each frequency. At Opensignal we used real-world data based on the 4G mobile network infrastructure that our users connected to, and found that operators exhibit different proportions of cells utilizing various bands, suggesting their 4G deployment strategies were shaped by their respective spectrum holdings. We found that Swisscom depends more heavily on mid-and high-bands spectrum,with over 50% of the cells serving the 1800 MHz and above bands.

Our measurements show Sunrise exhibited the highest proportion of 4G cells utilizing sub-1 GHz bands, with at least four out of every 10 cells transmitting data on the 800 MHz or 900 MHz bands. This greater use of low-frequency bands was also evident in our recent national report, where the operator won our 4G Availability award, but lagged behind in Download Speed Experience. Meanwhile, Salt and Swisscom had 34% and 27% of cells serving the  sub-1 GHz band.

Moving up to the comparatively higher-capacity 1800 MHz airwaves, we saw more than 50% of cells on Salt’s network in this band, while 44% of cells on Sunrise’s and 38% of cells on Swisscom’s network transmitted data on this frequency band. The 1800 MHz band strikes a good balance between coverage and capacity, falling between the extremes of the over 2 GHz and sub-1 GHz MHz bands.

The game changer in terms of speed, however, seems to be frequencies above 2 GHz, which don’t fare so well over long distances but are ideal for densely populated areas such as city centers. Our measurements show that 35% of cells we see transmitting data on Swisscom’s network used 2100 MHz and 2600 MHz spectrum –– which helps to explain why 36% of our users on Swisscom’s network were able to experience 4G Download Speeds above 50 Mbps. This also undoubtedly helped Swisscom win our Download Speed Experience award in our recent report. Less than 15% of cells on Salt’s and Sunrise’s network transmitted data on these frequency bands.

Switzerland is a small country with high population density that’s largely focused on a handful of urban areas — only 26% of the population inhabits the rural mountainous region. But the country's operators seem to have successfully managed their spectrum holdings to provide their users with a state-of-the-art mobile network experience. With the Federal Communications Commission (ComCom) having successfully auctioned a wide range of 5G-compatible mobile radio frequencies (700 MHz, 1400 MHz and 3500 MHz), and two operators having rolled out commercial 5G in more than 250 locations combined, Switzerland is set to replicate its 4G achievements with the next-generation technology.