Missing packets compared to Sniffle

[XenoKovah]

I set up capture for just channel 38 with ice9-sniffer as follows (from ticket #24):

./ice9-bluetooth -l -c 2427 -C 8 -sv -i bladerf0 -w ice9CH38.pcap

And then I let it run for ~10 seconds, because I know it is in direct physical proximity to a custom advertiser.

When I dump a summary of the pcap with tshark, I see very few packets, despite the fact that I know the advertiser is sending a lot of ADV_INDs:

tshark -r ice9CH38.pcap 
    1   0.000000 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    2   0.735162              →              LE LL 36 L2CAP Fragment Start
    3   1.986453 13:37:be:cf:00:01 → Broadcast    LE LL 36 ADV_IND
    4   2.195894              →              LE LL 36 
    5   3.449131 11:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    6   3.870494              →              LE LL 36 

I set up Sniffle to sniff only channel 38 with a Sonoff TI1352 dongle as follows:

sudo python3 sniff_receiver.py -s /dev/ttyUSB0 -m 13:37:be:ef:00:01 -c 38 -o sniffleCH38.pca

I told it to filter down to only the BDADDR 13:37:be:ef:00:01 of the advertiser, just so I could see its approximate advertisement frequency (even though I'm only listening on 1 channel, not all 3). So what is shown in Sniffle should be a subset of the other potential packets that occurred on channel 38 during the same time period. Dumping the pcap from Sniffle, we can see it captured a lot more packets over the same basic timeframe:

tshark -r sniffleCH38.pcap 
    1   0.000000 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    2   0.102657 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    3   0.204705 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    4   0.313130 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    5   0.418778 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    6   0.520613 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    7   0.627543 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    8   0.735420 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
    9   0.842593 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   10   0.947235 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   11   1.048949 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   12   1.153651 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   13   1.256522 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   14   1.361315 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   15   1.468398 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   16   1.571697 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   17   1.678842 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   18   1.781896 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   19   1.888094 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   20   1.992278 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   21   2.094020 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   22   2.195733 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   23   2.300375 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   24   2.405046 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   25   2.513868 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   26   2.615305 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   27   2.716012 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   28   2.822606 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   29   2.928223 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   30   3.031615 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   31   3.137903 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   32   3.240623 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   33   3.347339 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   34   3.448990 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   35   3.552258 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   36   3.654001 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   37   3.761817 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   38   3.868412 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   39   3.971771 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   40   4.076931 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   41   4.182976 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   42   4.288716 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   43   4.388721 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   44   4.493057 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   45   4.596813 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   46   4.702675 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   47   4.806981 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   48   5.014159 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   49   5.118618 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   50   5.219872 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   51   5.325001 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   52   5.430804 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   53   5.533705 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   54   5.642040 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   55   5.751807 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   56   5.858433 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   57   5.960510 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   58   6.070218 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   59   6.175622 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   60   6.280111 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   61   6.385790 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   62   6.495741 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   63   6.597088 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   64   6.806096 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   65   6.906312 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   66   7.015623 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   67   7.123379 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   68   7.228630 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   69   7.333119 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   70   7.436905 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   71   7.542127 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   72   7.652048 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   73   7.760901 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   74   7.868472 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   75   7.974854 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   76   8.081966 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND
   77   8.187341 13:37:be:ef:00:01 → Broadcast    LE LL 36 ADV_IND

Are there any things about the design of ice9-sniffer software or bladeRF hardware that would lead to this apparent rate limit of seeing packets only once per 1.5 when the actual rate is more like .1s?

[mikeryan]

There aren't any fundamental design limits that should be causing this. It's likely a case of my packet detection algorithms just not being very good. I have a few ideas for how to improve them and now seems like a good time to investigate that.

Do you still have base_name set to something? If so, clear out all the fc32/f32/txt files it's generated, and capture 1-2 seconds of your advertiser. Send me the generated fc32/f32/txt files and I can investigate in which part of the RX chain they're getting lost.

[XenoKovah]

files are in the attached example_capture.tar.gz, thanks