NRF7002 monitor mode sends signal out

RE: NRF7002 monitor mode sends signal out

Nulla — Fri, 10 Jan 2025 06:49:34 GMT

Hello,

No worries. Thank you for the explanation.

Currently, I will set your answer as verified, if we later need to change channel switch behaviour, we'll contact local sales manager.

RE: NRF7002 monitor mode sends signal out

Elfving — Thu, 09 Jan 2025 10:16:26 GMT

I've gotten a reply back from the relevant team now.

The Wi-Fi device has to do some channel calibrations every time a channel change is done to ensure best performance. Some short transmissions are required to accomplish these calibrations and you are seeing these in the spectrum analyzer when changing channels. This is expected. Note that when the Wi-Fi device is in the monitor mode, it will not do any SCAN, so CONFIG_WIFI_MGMT_FORCED_PASSIVE_SCAN does not affect operation in this mode.

So the current functionality available unfortunately doesn't allow you to ensure absolutely no TX during calibrations. If this is an important feature for you, please contact your local Regional Sales Manager about it (or ask me if you need info on who that would be for you).

Regards,

Elfving

RE: NRF7002 monitor mode sends signal out

Elfving — Wed, 08 Jan 2025 16:27:55 GMT

Sorry about the wait Nulla,

You might have to set the regulatory region, as whether or not active or passive scan being allowed varies between them.

I've asked about this internally, but in the meantime could you try setting CONFIG_NRF70_REG_DOMAIN?

Regards,

Elfving

RE: NRF7002 monitor mode sends signal out

Nulla — Wed, 08 Jan 2025 07:58:48 GMT

Hello Elfving,

Would it be possible to investigate why this signal occurs?

Best regards

RE: NRF7002 monitor mode sends signal out

Mike@PebbleStack — Fri, 03 Jan 2025 07:04:46 GMT

Hi Nulla,

It's way beyond my expertise, so I'll defer to someone from Nordic.

Happy New Year!

rgds...mike

RE: NRF7002 monitor mode sends signal out

Nulla — Fri, 03 Jan 2025 06:37:10 GMT

Hello,

Can I get any update on that please?

RE: NRF7002 monitor mode sends signal out

Nulla — Fri, 20 Dec 2024 07:08:10 GMT

Hello,

Yes, I tried using CONFIG_WIFI_MGMT_FORCED_PASSIVE_SCAN. This signal still appears.

RE: NRF7002 monitor mode sends signal out

Elfving — Thu, 19 Dec 2024 14:56:06 GMT

Hello,

Like Michael and the AI suggested, did you try CONFIG_WIFI_MGMT_FORCED_PASSIVE_SCAN?

Regards,

Elfving

RE: NRF7002 monitor mode sends signal out

Mike@PebbleStack — Thu, 19 Dec 2024 00:10:34 GMT

Have you tried using the AI? If found it really good at finding similar questions and suggesting answers.

Based on the information provided in the knowledge sources, I can address your question about the nRF7002 monitor mode sending signals out when changing Wi-Fi channels.

The behavior you're observing is likely related to the way the nRF7002 performs channel scanning and configuration. According to the [Wi-Fi regulatory support documentation](docs.nordicsemi.com/.../regulatory_support.html), the nRF70 Series devices typically use a combination of active and passive scanning, depending on the regulatory rules in place.

However, for monitor mode operation, we want to ensure that the device is only passively listening and not transmitting. To achieve this, you can try the following:

1. Enable forced passive scanning: As mentioned in the [DevZone forum post about nRF7000](devzone.nordicsemi.com/.../486207), you can set passive scanning in your configuration by setting "CONFIG_WIFI_MGMT_FORCED_PASSIVE_SCAN=y". This should prevent the device from performing active probing (transmitting) during channel changes.

2. Configure packet filter settings: The [Monitor mode receive operation filter configuration documentation](docs.nordicsemi.com/.../sniffer_rx_operation.html suggests that you can configure the type of IEEE 802.11 receive packets that the application receives. You might want to ensure that your filter settings are configured to receive only, without any transmission.

3. Check TX injection mode: Make sure that TX injection mode is not enabled unintentionally. As per the [Monitor mode receive operation in conjunction with TX injection documentation](docs.nordicsemi.com/.../sniffer_rx_operation.html, TX injection mode allows the transmission of raw 802.11 packets. Ensure that the `CONFIG_NRF70_RAW_DATA_TX` Kconfig option is not enabled in your project configuration unless you specifically need it.

If after applying these suggestions you still observe unwanted transmissions, it might be worth reaching out to Nordic Semiconductor's technical support for further assistance, as this behavior seems to contradict the expected operation of monitor mode.

Remember that the nRF7002 is designed to comply with various regulatory requirements, which might influence its behavior during channel changes. Always ensure that your usage complies with local regulatory standards for Wi-Fi devices.

An since it's AI, remember to verify any info provided before making any decision!