Is it possible to make the nRF5340 IC transmit a CW ?

[Per Hillersborg]

Hello

Is it possible to make the nRF5340 IC transmit a CW ?

BR Per

[Kenneth]

You can look at this example:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/peripheral/radio_test/README.html 

I did make a small modification of the above example that can setup a fixed modulated carrier without uart, in case it can be of use.

6472.radio_test.zip

If you want an unmodulated carrier you can try to use test_config.type = UNMODULATED_TX, instead of MODULATED_TX.

Kenneth

[Per Hillersborg]

Hi I have some additional questions.

Q1: Is the (TX) CW, a normal CW (pure sine tone) or is it a burst'ed CW ?

Q2: Can the CW be used to estimate the TX RF transmitting output power (RFPHY/TRM/BV-01-C [Output power]) (I know that the Direct Test Mode (DTM) is the official way of testing BT, according BT SIG ?

Q3: Can the CW be used to estimate the Carrier frequency offset (RFPHY/TRM/BV-06-C [Carrier frequency offset and drift, uncoded data at 1 Ms/s]) ?

Q4:Can the CW be used to test the TX phase noise ?

Q5: Is there other ways to test the phase noise than using a CW ?

E.g. for clasic BT, EDR, the EVM test (2 or 3 MBit/s modulation characteristic) (RF/TRM/CA/BV-11-C [EDR Carrier Frequency Stability and Modulation Accuracy]) can perhaps be used (to some extend).

BR Per

[Kenneth]

Hello,

1. Pure carrier.

2-5. What is the backround to these questions? If you have access to for instance an Anritsu MT8852B it will measure all these characteristis within seconds using DTM as specified by BT core spec. In production test you can tdo a functional DTM test to verify the radio as suggested here:
https://infocenter.nordicsemi.com/topic/struct_appnotes/struct/appnotes_nan34.html 

Best regards,
Keneth