failures in getting SCAN_RSP packet for a SCAN_REQ packet

[Kaviya.S]

Hi,

I am sending a SCAN_REQ packet from my code after receiving an Advertising packet from the NRF5340 DUT. Sometimes I receive the SCAN_RSP packet, but other times I encounter failures. I have captured the Over-the-Air waveform log with the NRF52840 sniffer. In the snippet below, the sniffer indicates that the CRC matches for the SCAN_REQ packet, but I am not receiving a response from the DUT. I am conducting this test inside an RF chamber. Out of 50 attempts, I do not receive a response around 15 times. Could you please suggest possible reasons for these failures and areas where I can improve?

Regards,

Kaviya

   

[Simonr]

Hi

Can you share the full sniffer log, as well as what adv/scan/connection parameters you're using on your devices here? Have you enabled any logging in order to debug on the boards themselves to see if any error messages are returned from the peripheral? I don't have any clear ideas/suggestions as to what might cause this I'm afraid, and it seems very strange in a RF chamber without any other noise. Any chance the antenna design on the DUT is not optimal so that it doesn't receive these scan requests. One option is to try with an nRF5340 DK on both sides to see if you can reproduce it with two DKs as well. If you can't, it's likely HW related and we can review the HW files for you if you'd like.

Best regards,

Simon

[Kaviya.S]

Hi Simon,

Thank you for your response. I’ve made some improvements to the signal quality, and it seems to be working fine now. It turns out that poor signal quality was causing CRC failures, which was the root of the issue.

Best regards,

Kaviya

[Simonr]

I see, glad you were able to find the root cause Kaviya!

Best regards,

Simon