RX SNR testing

To measure Signal-to-Noise Ratio (SNR) correctly, the Carrier Wave (CW) offset must be +330 kHz for the M1 mode and +45 kHz for NB1.

The parameters and their values are the following:

3 – RX SNR
1 – ON
Note: "OFF" is not needed due to automatic stop.
3GPP band number. Use 24 for Global Positioning System (GPS) reception.
Frequency 100 kHz (,i.e. 2140 MHz is expressed as 21400).
RX signal power at the System in Package (SiP) antenna port in dBm.

Valid range from −127 to −25.

System mode.

Valid range 0–1. NB1 (0) or M1 (1).

Enabling AFC correction during SNR test.

1 – Enable

0 – Disable

If <param4> is not given, AFC correction is disabled.

Response syntax when <operation> is ON:

%XRFTEST: <snr>,<antenna_power>

The response parameters and their values are the following:

Result of the Serial Number (SNR) measurement in q4 dB. q4 means that dividing the result by 24 = 16 dB.
Measured signal power at the SiP antenna port in q8 dBm. q8 means divided dividing the result by 28 = 256 gives dBm.

The following command example enables the RX SNR measurement and RF receiver for Band 1, 2140.0 MHz, −65 dBm, M1 mode, AFC correction enabled:

%XRFTEST: 496,-17002
Note: 496/16 = 31 dB and −17002/256 = −66.4 dBm.