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I would like to ask if it is possible to receive UDP or TCP packets instead of just the Physical layer by configuring the wifi_rx.grc 1 flow graph in GNU Radio.

wifi_rx.grc 1 is from the example in gr-ieee80211 I am using a LimeSDR-Mini as rx source

Marvin Leong
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You can use the Wireshark Connector block to write the decoded frames in a PCAP file and inspect all layers with Wireshark/tcpdump/tshark just with like a normal WLAN card.

The flow graph you are referring to already contains these blocks albeit they are disabled by default. Click on them and click Enable in the context menu. Then run the flow graph and open the file in Wireshark. If you want live decoding you can write to a Linux pipe. See the rx_demo.sh script in the apps folder on how to do that.

bastibl
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  • I did enabled and use the Wireshark Connector but all I received was of type ieee 802.11 protocol headers with a length of roughly 27 - 140 bytes without the UDP packet. Most of the packets received are ACK. How can I set the number of ACK retries to zero and handle retransmits on higher layers? – Marvin Leong Feb 25 '19 at 19:00
  • There is no MAC implemented in gr-ieee802-11. It will not send ACKs and it will not wait for ACKs. Since you already see WLAN traffic in your dump, it just means that the frames you are looking for were not decoded. This can have many reasons (gain, hardware impairments like DC offset, PC not fast enough, bus not fast enough, etc etc) – bastibl Feb 26 '19 at 12:07