Mobile Coverage Explorer – Technical Detail
Mobile Coverage Explorer is a representation of the area covered by mobile networks around the world. It is supplied as raster data which has been created from submissions made directly to Collins Bartholomew or the GSMA from network operators who provide roaming detail for inclusion in the GSMA’s Network Coverage Maps web application. This data is supplemented with coverage created from OpenCelliD, the world’s largest open database of cell towers.
Mobile Coverage is released annually in January each year. This data release is named 2022. Any operator data received up to the end of the year 2021 is included in this release. The coverage data is supplied in two folders to differentiate the two sources of data – Data_MCE and Data_OCI.
Data_MCE
Coverages in the Data_MCE folder have been sourced directly from the network operators. However, not every operator has submitted data and so there are inevitable gaps in coverage. The following table shows the percentage number of operators in the latest release that have submitted their coverage data compared to the estimated total number of operators who are members of the GSMA with licences for each technology.
| Technology | % Operator Submissions |
| 2G | 47 |
| 3G | 49 |
| 4G | 28 |
| 5G | 2 |
In 2021, 22 operators submitted new or updated coverage data for inclusion in the MCE datasets.
There are two folders in Data_MCE:
Global – Contains the merged global coverages. The file naming convention is MCE_Global<Technology>_<DataRelease> where technology is either ‘2G’, ‘3G’, ‘4G’, or ‘5G’.
ByCountry – Contains subfolders for 2G, 3G, 4G, and 5G technologies. Each subfolder contains rasters depicting the network coverage in each country. A country is not defined by its border extent but rather by the coverage supplied by network operators with licences in that country. Countries are identified using their ISO 3166-1 code, and the file naming convention is MCE_<ISO2Code><Technology>_<DataRelease>.
Operators are asked to submit strong and variable signal strengths as defined below:
| Network Type | Strong/Indoor | Variable/Outdoor |
| 2G (GSM) | Greater than -92 dBm | -92 to -100 dBm |
| 3G (UMTS) | Greater than -92 dBm | -92 to -100 dBm |
| 4G (LTE) | Greater than -105 dBm | -105 to -120 dBm |
| 5G | Not yet classified | Not yet classified |
However, the data received from operators often does not include signal strength information or does not follow the above guidelines. Therefore, whilst the rasters retain the strong and variable distinctions, this inconsistency must be understood by the user.
The cell values in the MCE rasters are as follows: 1 – strong signal strength; 2 – variable signal strength
Data_OCI
Data in the Data_OCI folder has been created using OpenCelliD tower locations. These interpolated locations have been used as the centre points of a radius of coverage: 12 kilometres for GSM networks, 4km for 3G and 4G networks, and 500m for 5G networks. These circles of coverage from each tower have then been merged to create an overall representation of network coverage. The following limitations are noteworthy:
- The values for the radius of coverage from the tower locations are based on similar information provided by operator submissions, with a tendency towards minimum values.
- Tower locations are interpolated from the location of mobile phone users and so the coverage tends to be concentrated along routes and built-up areas.
- Only a small number of Android or Blackberry apps collect data and so the coverage tends to be concentrated in countries where certain apps are popular.
- The accuracy of tower locations is dependent on multiple measurements to the same tower. The tower’s location is the average position of mobile phone users receiving signals from that tower.
- The derived coverage does not take account of obstructing factors such as terrain variations
Because of these limitations, the OCI data is intended to fill the gaps where network operators have not yet submitted coverage data and should be viewed as an approximation only.
Further information on OpenCelliD tower locations can be found at their What Is OpenCelliD and Glossary pages.
It should also be noted that, despite online documentation from the likes of ITU and mcc-mnc.com, it is difficult to match the MNC codes within the OpenCelliD database to the correct network operator due to variations in operator names or the names of their parent companies. Every effort has been made to match the correct codes to operators where possible.
There are two folders in Data_OCI:
Global – Contains the merged global coverages. The file naming convention is OCI_Global<Technology>_<DataRelease> where technology is either ‘2G’, ‘3G’, ‘4G’, or ‘5G’.
ByCountry – Contains subfolders for 2G, 3G, 4G, and 5G technologies. Each subfolder contains rasters depicting the network coverage in each country. A country is not defined by its border extent but rather by the coverage created from operator networks in each country. Countries are identified using their ISO 3166-1 code, and the file naming convention is OCI_<ISO2Code><Technology>_<DataRelease>
The cell values in the OCI rasters are as follows: 1 – approximate coverage
Data Format
The data is made available in GeoTIFF as either 2-BIT (MCE) or 1-BIT (OCI) raster format with pre-built pyramids using nearest-neighbour resampling. The map projection used is Web Mercator (EPSG:3857), with a nominal resolution of approximately 260 metres on the ground at the equator.
Colourmaps showing strong and variable coverages where relevant are included with each raster.
If you have a requirement for data in a different format or map projection, then please contact us.
Metadata
Information on the individual networks included in the MCE and OCI folders is provided as an Excel spreadsheet called Mobile Coverage Explorer Metadata.xlsx. The columns in the spreadsheet are as follows:
OPERATOR_ID – a unique numerical identifier assigned to each network operator
NAME – the name of the network operator
CNTRY_ISO2 – the ISO 3166-1 country code used to describe the territory that the mobile network covers
COUNTRY – country name, in English, according to Collins Bartholomew’s naming policy
MCE_<Technology> – A date indicates that this network is included in the MCE coverage data. The date is the year when the operator’s coverage data was last updated.
OCI_<Technology> – A ‘Y’ indicates that this network is included in the OCI coverage data.
If an operator is not listed in the spreadsheet then they have not submitted coverage data to Collins Bartholomew and are not identified in the OpenCelliD database.
Changelog
As the method of processing the operator data submissions has evolved so too has this aggregated coverage. The following are the main changes between the annual releases:
- From 2010, Collins Bartholomew became the exclusive mapping partner to the GSMA. Datasets prior to this date were processed by previous partners and are available as a separate “Legacy” data product. Only the network data whose source is known in the ‘Legacy’ data has been included in the data from 2010 onwards.
- In 2021, all previous annual releases back to 2010 were recreated into a consistent raster format to allow easier comparison.
FAQs
Q: Is it possible to access individual operator networks in the data?
A: Unfortunately, the data is restricted to show merged country coverages only. This is to ensure that users are not able to make direct comparisons between operators which might show one operator unfavourably against another. We rely on operators voluntarily submitting their coverages to us to complete this global coverage dataset and so we do not want to discourage them from submitting this information.
Q: Is it possible to determine the growth or decline of network coverage over time?
A: Since the data is released annually then it is possible to analyse the change in network coverage over time. However, the data is limited to the networks that have been submitted by operators. Therefore, a change could be the result of a growth or decline of a network but it could also be because an operator has submitted data to us for the first time. Until we reach the stage where we have a high percentage of operators submitting their coverage data regularly, the data could be regarded as a record of increased operator submissions rather than the growth of network coverage.
Q. Why are some networks that existed in the Legacy 2009 Q1 release not included in subsequent releases?
A. Collins Bartholomew became the official mapping partner to the GSMA in 2010 and we have created the 2010 annual data release using the network data that was made available to us up to the end of 2009. Simply merging the global 2009 Q1 data with the networks made available to us would have introduced data whose source is unknown, and would have made it difficult to remove networks as they are switched off over time. For that reason, the datasets from 2010 exist separately from the Legacy datasets created up to 2009 Q1.