Mobile signal strength measurement data from Network Rail's engineering trains
Since October 2017, Ofcom has been collecting data related to mobile signal strengths along the rail network in England, Scotland and Wales, using antennas mounted on the top of four of Network Rail’s yellow engineering trains (“the yellow trains”).
The data collected between June 2018 and June 2019 is plotted on the maps below.
The raw data was over 5GB in size, so to improve performance the data was rationalised to keep no more than one sample for each 10m.
The data represents the strongest mobile signal (per mobile operator) received at the antenna on the roof of the train; it is therefore not representative of the mobile signal a passenger would
expect to receive inside a train travelling on the same route, or an worker would expect to receive working at track level. (The signal in modern trains is often hindered by metalised windows used for their thermal properties).
The data includes measurements for 2G, 3G and 4G mobile signal, which have been plotted on separate maps, using Tableau. You can use the tick boxes to select specific operators if desired.
(It's a little bit slow due to the volume of data, but hopefully useable with modest patience)