7002 scan parameter

[William.wei]

hi support team,

customer is asking about how to using 7002 to scan 2.4g wifi or 5g wifi only, and want to know if 2.4g only will accelerate the scan duration time.

i could not find the parameter to set this for scan_info. and want to know exactly the coding if possible from Nordic 7002 side

Regards,

William.

[Simonr]

Hi William

Please check out the config WIFI_SCAN_BANDS_LIST in the wifi->scan project's Kconfig file. Here you can set the scanning band list to either 2 or 5 to scan on the 2.4GHz or 5GHz band respectively or 2, 5 to use both.

Best regards,

Simon

[William.wei]

Thanks Simonr,

one more question is from scan request to scan request done, the time it tooks is decided by what parameter.

or how it works? each channel one by one till the last channel?

the reason for this is, it tooks more than 4 seconds for one band only, it costs some current.

Regards,

William.

[Simonr]

Hi William

Sorry, but I don't know what pattern exactly is used for scanning, but I think it's random. 

By changing the wifi_scan_params you should be able to I.E. lower the dwell time on each channel so the scan will take less time I think, as the default in the sample is 50ms for each channel, or 130ms in Passive scan mode.

Best regards,

Simon

[William.wei]

Thanks Simonr,

i did the test with wifi scan demo, and looks like there is something wrong.

i set to scan 5g only and set passive scan time to 260 and 390 and 520, and scan done callback is returned accordingly:

the time spent for scaning is consistent to "CONFIG_WIFI_MGMT_SCAN_DWELL_TIME_PASSIVE"

CONFIG_WIFI_MGMT_SCAN_DWELL_TIME_ACTIVE=50

CONFIG_WIFI_MGMT_SCAN_DWELL_TIME_PASSIVE=520

CONFIG_WIFI_SCAN_BANDS_LIST="5"

it looks like we are scaning using passive scan mode, not active scan mode;

however, i can see that we set this to active scan:

another question is:

the default CONFIG_WIFI_SCAN_CHAN_LIST="", not as listed as:

may i ask how many channels are scaned in 5g band?

Regards,

William.

[Simonr]

Hi William

What times do you measure here where you decide it's using the passive scan parameter? From scan requested to scan request complete there are multiple seconds in these screenshots, and from num ID to scan request done it seems much closer to the ACTIVE parameter of 50ms. That being said, are you sure these time stamps come from the application and not the logger, as the logger/serial port setting the timestamps will not necessarily be the correct times of when this occurs.

From the snippet you share, the default channels that are used to scan on the 5GHz band are channels should be channels 36, 40, 44, 48, 149, 153, 157, 161 and 165 on the 5GHz band when you set the 5GHz band only. I'm not sure I understand what you're asking as the logs you share also seem to coincide with these channels.

Best regards,

Simon