Can Link Quality Indication be viewed as Signal to Noise ratio?

[shreyas_patel21]

Hello Everyone!

I am using RF transceiver of atmel and it gives me some reading of RSSI and LQI in its register.
I need to display signal to noise ratio of RF signal, but there is not direct register for that.
How can I get signal to noise ratio?
can LQI gives measure of SNR? or what is the equation for SNR from RSSI and LQI?

Regards,
shreyas.

 

[vfone]

The RSSI is the sum of the pure received signal and the noise floor at the receiver.
The SNR describes how strong the pure received signal is in comparison with the receiver noise floor.
As the noise floor at different nodes can be different, the SNR metric should be better link quality estimator than RSSI.
Generally LQI is based on PER packet-error-ratio (or PRR packet-reception-ratio).
LQI can give a rough estimation for SNR, better than RSSI.

 

[shreyas_patel21]

Is there any equation for calculating SNR from LQI? what is the relation between SNR and LQI? If it can give the rough estimation then how can we get proper value of SNR?