Non-modulated emissions in 802.15.4

RE: Non-modulated emissions in 802.15.4

Carton_ — Mon, 14 Nov 2022 13:22:58 GMT

Thanks!

RE: Non-modulated emissions in 802.15.4

ketiljo — Mon, 14 Nov 2022 13:21:08 GMT

Yes, this is most likely what happens.

RE: Non-modulated emissions in 802.15.4

Carton_ — Fri, 11 Nov 2022 12:19:43 GMT

Hi,

Thanks a lot for your answer!

So could my issue be related to this part of the RADIO section in nrf52840 documentation:

As illustrated in Transmit sequence the RADIO will by default transmit '1's between READY and START, and between END and DISABLED. What is transmitted can be programmed through the DTX field in the MODECNF0 register.

RIOT OS driver doesn't use shortcut between END events and DISABLED.

RE: Non-modulated emissions in 802.15.4

ketiljo — Fri, 11 Nov 2022 09:36:12 GMT

It looks like it's the RIOS OS radio driver that does this. It seems to keep the TX on after the modulation is finished at the end of the packet.

This is how a 15.4 carrier looks like when the radio test example is used to setup a carrier.50% duty cycle just to have some on/off toggling.

The radio test example (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/peripheral/radio_test/README.html) uses the NCS radio driver.