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min max RSSI values

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I have a project where I like to trilaterate the position a client using 3 provided RSSI feedbacks from 3 different positions. It would be helpful to know the quantisation of the RSSI feedback of the products XBee-Pro ZigBee, XBee Wi-Fi and XBee DigiMesh 2.4. using the "DB" command from the commandset.
As RSSI values tend to differ from vendor to vendor, What value range can I expect?
asked Mar 22, 2016 in RF Solutions and XBee by c_m New to the Community (0 points)

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1 Answer

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Do not use a Mesh product for this. You really need to use a Point to point or a point to multi-point product. Trying to use a Mesh product with a remote AT command will only allow you to get the RSSI level of the Remote AT command and not the value you are looking for.

Now if you want to use say the Digi Mesh 900 H, then you may be able to use some of the Diagnostic features to do what you want.
answered Mar 22, 2016 by mvut Veteran of the Digi Community (12,354 points)
Thanks for your answer.
I don't intend to measure the RSSI via remote command over a mesh network as I know the DB command only gets me the RSSI of the last hop. Nevertheless, having only 2 DigiMesh modules communicating with another, that would be a point-to-point-connection, in this case wouldn't the DB command give me exactly what I seek?

I am interested in the value range for this case. The DB command gets me the RSSI as a hexadecimal, the manual having an example "0x60 = -96dBm" but not specifying a value range.
Am I correct in assuming that the maximum value is 0x00 for highest signal strength, and the minimum value is around the value of the sensitivity of the modules (as they can't quantise the RSSI any further)?
Still a mesh product should not be used for this.  I would strongly recommend using something like the XBee 802.15.4 module.  They will give you the ability to see the RSSI level in a Point to point, peer to peer or point to multi-point network topology.

If I recall, the RSSI runs through one of the Analog channels so the value ranges from the receiver sensitivity on the low end to about -40 on the high side.
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