Finding Distance From Driver Station

[Mark McLeod]

I don't follow what useful data you are looking to collect.

Are you looking for the latency of the robot's wireless bridge to FMS Access Point to derive the robot's distance from the AP?
Sounds like a step towards Zigbee triangulation...

All the rest of the communications are over a wired network with near-identical lengths of Ethernet cable, regardless of the Driver Station physical location. They'll all be at identical (wired) distance from the field Access Point, so I don't see that data as being useful.
It seems like any single ping (FMS or DS) would produce the same information, i.e. distance to AP or maybe length of the field Ethernet cables, speed of the network switches, frequency of collisions if you stretch it...
Assuming network collisions and retransmitted TCP/IP packets don't mess up your timings entirely...