CC3235S: Is there any way to measure the field strength of any emission?

Hi Masashi,

In case we talk about radiated emissions, common way is to use spectrum analyser and proper far near and far field antenna (depending on what exactly you want to measure). But proper quantification may to be challenge due to calibration of measurement chain. For proper measurement is anechoic chamber required as well. If you not have available such equipment, you need to ask 3rd party. Be aware that such measurement from 3rd party will not be cheap.

For conductive measurement you can use spectrum analyser or wireless protocol analyser like devices from LitePoint, Keysight, R&S, etc. Budget alternative for spectrum analyser can be some SDR with 5GHz capability.

If you not have available such RF equipment, you can try to use some other WiFi device (cell phone, wireless network sniffer). But your results will be very raw and you will be able measure IEEE 802.11 communication only. Btw ... there are some models of AP (e.g. some types from Ubiquiti) with capability to scan RF background.

Update: if you are interesting about selecting less occupied channel from CC3235 code before starting AP mode, you can do WLAN scan and select less occupied channel. But you decision will be based on RSSI from WiFi management frames and will not count interferences from other 2.4GHz protocols.

Jan

Dear Jan,

Thank you for your detailed answer.

Please forgive me for the lack of explanation.

I want to do a radio channel scan to dynamically determine the AP's channel when the CC3235 device starts up.

In my understanding, I can use the API function "sl_WlanGetNetworkList ()" to get the AP scan results.

Is there any API function for CC3235 that can scan signal strengths other than AP?

Best Regards,

Masashi