Xbee Series 2 localization

Question

Hi guys, Im playing with some Xbee's modules. i made a small mesh network having 1 Coordinator + 1 Router + 1 End Device (All in API mode)

I'am trying to track the EndDevice :
1- i used the node discovery command (ND) from the Coordinator but it seems that this command list all the node's network and not only the nearby Xbee's.
2- i have tried the RSSI mecanisme and used the DB command but seems to give the RSSI from the last hope only !

I really don't know what to do next ...

Any hints are welcome. Thanks

Answer 1

Hi Sad,

That's correct. ND will find all nodes on the network, at least in theory.

DB will only show you the RSSI on the last received packet.

Keith

Comments

Hi Keith,
Any idea how to implement an RTLS system using a mesh network with XBee ZB S2 ?

I have started like this :
1- From the End Device i do a ND cmd
2- For each ND response, i send a ping to the node if it is a Router
3- From the Router : i receive the Ping and do a DB command to get the RSSI

But i won't get the correct RSSI as will get the RSSI of the last hop !!

Best regards

Answer 2

Hi Keith,

Sorry for being late.

I have switched to Xbee S1 so that i can get easily the RSSI without caring about 'hops' as no mesh any more.

Here is my setup : http://www.casimages.com/img.php?i=131113032946894827.png

Xbee N°4 has internet access
Xbee's N°2 and N°3 are fixed into the wall
Xbee N°1 is the mobile one.

---

XB1 is broadcasting each 5sec
XB2 and XB3 are listening and once they get a message from XB1 they get the RSSI from it.

==> Now the question is how can XB2 & XB3 transmit the final result to the gateway (XB4). ? in my situation only XB3 can transmit to the gateway as it is in the range. but not XB2.

Mesh would be helpful here but i cannot use it in that kind of projects due to the last hop issue ...

Any hints are welcome. and sorry for my bad English
BR