UMTS 3g cell id

#1

Hi there!

I’m currently trying to get a match for a BOUYGUES cell id in france:
We know for sure that the report from the tower should be 208 20 4F61 0176, active in dec 2018.
On the map, we get various LAC that are the same in decimal, 20321, but I cannot translate the Cell ID into any number we found on the CID of any cell tower near the location.

It could be a cell near the location mapped out as:
208 20 20321 93847836, which position is 46.002419; 4.101914, measured in february 2019.
How OpenCellid creates/reads those CID?

can you help me with that?
Thanks,

L.

#2

Hi,

Can you confirm the CID you’re seeing is 0176? We generally see a longer CID, but its entirely possible we do not have data on that particular identifier.

#3

Hi Sagar,

Thank you for your response
For context, those numbers come from a very badly printed police report. We are trying to help with the investigation !
We are working from a printed doc from 2018, where we can find various ‘antenne relais’ data:
We managed to find out all the 4g LTE cells id from the same doc, which are from the same area.
And we are still missing the following 3G cell ID:

20820 4F61 01 C0
20820 4F61 01 5 - ending by 0 or E
20820 4F61 01 76

It’s crucial for us to locate those cells to prove that the mobile user was at that time in a certain area of the city!
Thank you for any help you can provide!

#4

20820 4F61 01 C0
20820 4F61 01 5 - ending by 0 or E
20820 4F61 01 76

Each cell has a unique identifier in the format MCC-MNC-LAC-CID. From the data you shared:

MCC: 208
MNC: 20
LAC: 4F61 (20321 when converted to decimal)
CID: 93847836 (from your first message)

According to our database, we have it that cell identifier here:

{
    "status": "ok",
    "balance": 5099,
    "lat": 46.010702,
    "lon": 4.092223,
    "accuracy": 2583,
    "address": "Chemin du Domaine Berger, Le Coteau, Roanne, Loire, Auvergne-Rhône-Alpes, Metropolitan France, 42120, France",
    "address_detail": {
        "county": "Loire",
        "state": "Auvergne-Rhône-Alpes",
        "country": "France",
        "country_code": "FR",
        "postal_code": "42120",
        "road": "Chemin du Domaine Berger"
    }
}

The accuracy of 2583 indicates an error margin.

How OpenCellid creates/reads those CID?

OpenCelliD data is contributed by volunteers from the community via observations from devices.

#5

Hi Sagar,

Thank you for your response!
To be super clear: We are trying to locate (approximately) a person at a precise time and date.
This person was working and during work hours, is connected to 3g and 4g cells, according to the report from the company, that the police shared with us. Then this person took their car to a more rural area, through the highway, exited the highway, took a secondary road and killed my brother-in-law, to be super clear.

What we are trying to do here is to show that it was speeding before the accident. We have the time of the handovers and the lenght of the connection to each cell in the report, and we were able to locate all the 4G thanks to cell id.

Our problem is to understand how Bouygues, the company, is coding the Cell ID of its 3g cells because it feels too short, since only the last two digits are changing. For sure its mapped out in OpenCellId with a different number, which is very frustrating!

Still looking for this 3 Cell Ids :

20820 4F61 01 C0
20820 4F61 01 5D
20820 4F61 01 76

Do you have an idea on how to translate those data?
Thanks a lot,

L.