600 Mbit/s Outside – 6 Mbit/s Inside

5G is slowly making its way into Cologne with incredible date rates. Recently, however, I discovered just what it means to have a simple insulating window between you and the network outside.

When I was recently asked to propose a place for dinner in Cologne, I  chose a restaurant that was right in between three 5G cell sites with n78 coverage. Yes, I wouldn’t let such an opportunity pass by to do a little experiment… Among other reasons, I chose the restaurant because it lay exactly in between those three cell site. In other words, I was at the cell edge between 3 locations, which means there’s a lot of interference, at least on the LTE layer.

Before entering the restaurant I checked the street level coverage. All three cell sites were not in the street so I had no direct line of site to any of the antennas and coverage is provided by reflections. Still, the 4G and 5G signal level was strong and due to the 5G n78 coverage I got 600 Mbit/s in the downlink direction out of the channel. Nice!

Then I entered the restaurant and the radio situation changed completely. The n78 layer on 3.6 GHz, gone. The LTE layer on band 7 (2.6 GHz) gone. The LTE layer on band 3 (1.8 GHz) gone. The only thing that remained was a 5 MHz LTE carrier on band 8 (900 MHz) with a measly RSRP of -110 dBm. Once through an insulating window, at a table 2 meters inside the restaurant, and my speed dropped from 600 Mbit/s to 6 Mbit/s. Wow!

Don’t get me wrong, I don’t want to complain, because the alternative to LTE on band 8 or band 20 is EDGE. And I really don’t want to be in EDGEland anymore.