The infusion of the 700 MHz airwaves into operators’ 4G networks produced visible improvements in the national scores of our latest Brazil report as operators activated the new frequency band across Brazilian cities. However, we observed a trade-off between increased 4G networks’ reach and 4G Download Speeds. In Rio de Janeiro we were able to see this trend in action: While 700 MHz didn't produce any big jumps in 4G Download Speed it improved the level of access to 4G significantly by penetrating further into buildings. That in turn led to an improved mobile experience as our users were able to tap into more powerful 4G signals more often.
Opensignal analyzed the recent rollout of the 700 MHz frequency band in Rio de Janeiro and observed that 4G Availability increased. Our data indicates that smartphone users accessed 4G networks on the 700 MHz band in similar areas as existing 2100 MHz and 2600 MHz bands, and therefore suggests that the good indoor penetration of the sub-1 GHz band likely explained the increased availability. But because of the limited capacity of the sub-1 GHz band, when our users connected on the 700 MHz band, they experienced on average 20 Mbps lower 4G Download Speed than on the 2600 MHz band.
4G Availability surged following the 700 MHz deployments
Opensignal observed that 4G Availability in Rio de Janeiro steadily increased from 69.9% at the beginning of 2018 to 77.7% at the end of March 2019. However, while the quarter-over-quarter gains were around 1% at the beginning of 2018, they have more than doubled since Claro, TIM and Vivo started using the 700 MHz band in their Rio de Janeiro’s 4G networks in June 2018.
The 700 MHz band is particularly suitable for mobile broadband services because of two main features: good signal propagation — which makes it attractive to increase the reach of 4G networks — and indoor penetration — because it experiences less signal strength loss inside buildings. So, we wondered which one of the two features carried the largest benefit for our smartphone users in Rio de Janeiro.
Users accessed 4G networks on the new 700 MHz band in similar areas than those where they connected using 2100 MHz and 2600 MHz bands
Opensignal analyzed our users’ experience on different 4G spectrum bands in Rio de Janeiro. We started by looking at the reach of different frequency bands in the locations where our users spent their time, and plotted our measurements grouped by spectrum band in the maps below.
The first map shows the places in Rio de Janeiro where our users connected to 4G networks on the newly-deployed 700 MHz band. This band offers good signal propagation and good coverage but has more limited capacity and typically supports lower speeds.
The second map shows the locations where our smartphone users connected to 4G networks on the pre-existing 2100 MHz and 2600 MHz bands. These bands offer higher capacity but possess lower signal propagation.
In both maps we see our measurements widespread across the urban areas, indicating that our smartphone users accessed 4G networks on both 700 MHz and pre-existing higher frequency bands in the locations where they spent most of their time. We also noticed that our combined measurements on 2100 MHz and 2600 MHz bands appeared to include more locations on the second map compared to those connected to 700 MHz band in the first map, suggesting that smartphone users were more likely to connect to the higher frequency bands than to 700 MHz band.
Opensignal’s visual analysis of Rio de Janeiro’s 4G frequencies indicates that the 700 MHz band is generally deployed in similar areas as the 2100 MHz and 2600 MHz bands, suggesting that the significant increase in 4G Availability we measured since the 700 MHz deployment was likely related to the second key feature of the sub-1 GHz band: improved indoor propagation. This suggests that smartphone users were now more likely to keep connecting to 4G networks when moving inside buildings thanks to the better indoor penetration of the 700 MHz band.
Smartphone users experienced 20 Mbps lower 4G Download Speed when connected to 700 MHz instead of 2600 MHz
Opensignal analyzed the download speeds our users experienced when they connected to 4G networks on different spectrum bands, and found that they varied widely.
Our smartphone users in Rio de Janeiro on average enjoyed 33.9 Mbps in 4G Download Speed when they connected to 4G networks on the 2600 MHz band. But when they could not access LTE networks on the higher 4G frequency band, and connected on either the 1800 MHz or 700 MHz bands, their average 4G Download Speed dropped by more than 20 Mbps.
Opensignal’s data suggests that smartphone users in the urban area of Rio de Janeiro benefitted from the deployment of the 700 MHz band in terms of extended 4G reach and additional time they could access 4G networks, thanks to the better indoor penetration of the newly deployed sub-1 GHz band. But when users connected to the 700 MHz band, they experienced on average a lower 4G Download Speed of 13.2 Mbps, highlighting the limited capacity of the spectrum band, and the necessary trade-off between increased reach and faster speeds.