Unable to sniff CTE packets in wireshark with nRF52840

[Lihua.Liu]

Good day,

We developed AOA transmitter with nRF52833. It works great, able to send out all the packets correctly, including periodic advertising packet with CTE, here is the source code if you are interested github.com/.../c209-aoa-tag

I am trying to use nRF52840 to sniff the periodic advertising packet, and analysis the carried CTE.

I am able to find the advertising packets from the advertising channels(37,38,39), and I could find AUX_ADV_IND packet after that in the data channel, but I can not find periodic advertising packet in the data channel. 

Below attach the AUX_ADV_IND packet, it doesn't show where to find the AUX_SYNC_IND packet. 

Any suggestion is appreciated, or do I have to use a aoa supported chip in order to see CTE packet?

BR

Lihua

[Simonr]

Hi Lihua

I'll have to ask the team behind the nRF Sniffer internally about this as I'm not sure if this is supported (we don't mention this feature/support in the nRF Sniffer release notes at least), but my guess is that you will at least have to use a chipset that support Direction Finding and CTE to sniff CTE data.

Best regards,

Simon

[piethan]

Hello, on my machine I can read the CTE info field you picture with an NRF52840 and the NRF sniffer/wireshark software. I have almost the same setup, being NRF52833 transmitting CTE on periodic packet and NRF52840 receiving. I'm sure it doesn't actually read the CTE part of the packet, but I can confirm it for sure can read the CTE info in the extended headers. 

[Simonr]

Hi

This would most likely be because the nRF52840 doesn't support AOA or CTE packets, and thus won't be able to read the CTE part of an advertising packet. You will need to have I.E. an nRF52833 on both ends of the communication to correctly transmit and receive CTE data correctly.

Best regards,

Simon