Receive very short bursts with LimeSDR

Can some hardware or software limitations prevent LimeSDR to receive short burst?

Recently I tried to receive Wi-Fi signals from access point. I can successfully see transmitted frames on waterfall but do not see any trace of beacon frames. They should be transmitted about 10 times per second but their duration is very short.

I tried to use Gnuradio 3.7 and GQRX 2.6 for these tests.

Any ideas?

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try using gr-fosphor in gnuradio instead of a normal fft-sink. this should show EVERY sample, so the waterfall is very fast

Thanks for suggestion!
I believe it is not the case of fft sink in gnuradio.
I tried to record the IQ file in gqrx and then analyze it with baudline. No traces of beacons even with big zoom. I think that using fft sink should not affect iq file being recorded as stream from LimeSDR.

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just wondering…
You managed to run gr-fosphor and Lime on ubuntu?


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I’ve had success with LimeSDR and gr-ieee802-11.

Examples/wifi_rx will create a PCAP you can look at in wireshark. The beacon frames will be there if everything works ok.

The osmocom source settings that I got to work:

RF Gain: 10
Device Arguments = driver=lime,soapy=0
IF Gain: 20
BB Gain: 20
Sample Rate: 20e6
Frequency: 2.412e9
Antenna: LNAW

You’ll need to play with some of the parameters based on what channels are around you, specifically the frequency. You should be able to occasionally observe nice little bumps in the frequency plot when you’ve tuned to a good frequency and gain settings are acceptable.