Xbee node selection by range from main Xbee

Hi

Have tried google it but not sure what search terms to use.
I need some help figuring out how to get a main Xbee talking to the Xbee node thats closest.

Made some overview images, hope this explains it good enough.

The different Xbee nodes are sending sensor values, so the main Xbee needs to receive the values thats most relevant to its position.

Many thanks!

There is an assumption in your question that will be very difficult to deal with. That is, the "main XBee" has ti know which other XBee is closest. How do you propose to know that?

Once you do, talking to that specific XBee should be trivial.

All of the nodes and the main will have gps

All of the nodes and the main will have gps

Fine. Then as long as each XBee sends it's location, you can determine the closest one, and communicate with just that one.

What will you do if that particular XBee, or the master, moves, so that XBee is no longer the closest one?