RE: One question about nRF9160 LTE RX test.

Hakon — Tue, 26 Apr 2022 11:16:02 GMT

Their response;

https://infocenter.nordicsemi.com/pdf/nrf91_at_commands_v2.0.pdf
--> Chapter 11.5 RX SNR test %XRFTEST

"The set command measures SNR.
To measure SNR correctly, the CW offset must be +330 kHz for the LTE-M mode and +45 kHz for the NB-IoT
mode."

--> This means not modulated sinusoidal RF signal offset from Channel Center Frequency set by %XRFTEST <param1> described in chapter 11.5

--> To set maximum gain for receiver recommended CW signal level is around -90dBm at nRF9160 LTE input pin, hence expected SNR result is in range 16...18dB.

--> For Rx SNR measurement it is recommended to use AFC calibration (Chapter 11.6) prior SNR test to get correct SNR result.

RE: One question about nRF9160 LTE RX test.

Hakon — Mon, 25 Apr 2022 11:05:24 GMT

Hello,

I have informed the modem team about this.