The identification of users positioning is a challenge in any Mobile Network.
Having accurate information allows you to do a better Planning, Optimization and so on.
There are several ways to find it, for example using Tools (both commercial and free/open source).
One way is to use crowdsourcing tools (Telecom Crowd-sourced Data).
Also, you can do Traces and Drive Tests.
You can also find it using counters (every vendor has their own set of counters - but basically same info).
Counters are TA (Timing Advance) in 2G and 4G, and PD (Propagation Delay) in 3G and 4G.
(I wrote an article about it long time ago, when i was working in Design & Optimisation → Analyzing Coverage with Propagation Delay - PD and Timing Advance - TA (GSM-WCDMA-LTE)
I am working with telecomHall team to bring this kind of features in the new coming Hunter CE tool → Hunter CE - Before we begin