I teach a non-geographical technical course, and the topic will be triangulation (..of suspects via mobile phone signals while using an archived well-known case). Since the system in questioned is GSM, we/they used the TA value (distance from tower quantized from [0:63], where each step is ~550 meters). So if TA is (eg.) 10, the distance from the tower is (in an ideal case) from "10*550m" to "10*550m+549.99m".
I have coordinates of three towers in lat,lon (WGS84), I have the TA values, and I would like to draw three donut shapes (inner radius=ta*550m, outer (ta+1)*550m) which would ideally intersect in one relatively small area. I also have a raster map (satellite images). I have already verified the raster layer and the basestation points are visualised OK, but I have no idea how to draw the 'donuts' (except photoshop and eyeballing it).
What would be the simplest way to visualise that in QGIS?