TX functionality test

The %XRFTEST TX test enables the RF transmitter with the given parameters. It also returns the internal measurement result of TX power. OFF <operation> disables the RF transmitter.

Using high TX power levels results in high current consumption. This should be considered in the power supply setup if several products are tested in parallel.

Note: Starting the %XRFTEST TX test with a high power level causes RF disturbance that may interfere with other cellular users. Using an RF shielded chamber for this kind of testing is recommended.

nRF9160 responds to the %XRFTEST TX test with the measured TX power at the antenna. The power level is given in the q4 (dB) format. Dividing the result by 2⁴ = 16 gives the dB value of the antenna power.

The following command example executes a TX test:

%XRFTEST=1,1,5,8300,17,0,3,12,0,0,0,0,0 // TX ON (B5,830.0MHz,+17dBm, NB1,BPSK,12 tones, tone
start position 0, subcarrier spacing 15kHz, system BW NB1, NB index 0, TX burst mode disabled)
%XRFTEST: 271	// Result: 271/16 = 16.9dBm OK

%XRFTEST=1,0	// TX OFF OK

The TX functionality test input parameters are described in the following table:

Table 1. Input parameters of TX functionality test
Parameter name	Parameter description	Range	Value description
<param0>	3GPP band number	1–66	Bands supported by nRF9160
<param1>	Frequency 100 kHz raster	6000–22000	Corresponds to 600–2200 MHz
<param2>	TX signal power	+23 to –50	TX signal power at the antenna
<param3>	System mode	0–1	NB1 = 0 M1 = 1
<param4>	Modulation	CW– 16QAM	TX signal properties. Available options depend on the selected system mode.
<param5>	Resource Block (RB) or SC count	1–12	TX signal properties. Available options depend on the selected system mode.
<param6>	RB or SC start position	0–11	TX signal properties. Available options depend on the selected system mode.
<param7>	Subcarrier spacing	0–1	TX signal properties. Available options depend on the selected system mode.
<param8>	System bandwidth	0–4	TX signal properties. Available options depend on the selected system mode.
<param9>	Narrowband index	0–3	TX signal properties. Available options depend on the selected system mode.
<param10>	TX burst mode	0–1	TX signal properties. Enables non-continuous TX transmission.

For details on parameters supported by each modem firmware release, see nRF91 AT Commands Reference Guide.

For bands supported by nRF9160, see nRF9160 Product Specification.

For more information on TX testing with the %XRFTEST AT command, see TX test %XRFTEST in nRF91 AT Commands Reference Guide.