How to get rssi value from Digi XBee-PRO 900HP module

I am new to Xbee and so far I figure out how to send and receive data but I was unable to get any RSSI value. My setup is as follows:
I have one module that will send device data and two modules that will receive that data. I also need to get RSSI value from two Rx modules since Tx module may change position in respect to two Rx modules. The RSSI data will be used to estimate position of the Tx device (closer to Rx1 or Rx2 module). I have Digi XBee-PRO 900HP kit.
Any help will be greatly appreciated.

Thanks.

You have to use the DB command/API frame (remember to prefix with AT, and enable command mode with +++ and waiting for OK response, if you are using transparent mode). With API mode it’s just a frame command you can send. This setup will also not work with DigiMesh because it only shows you the last hop.