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PCAP file writer of protocol packets


    The pcapWriter object writes generated and recovered protocol packets to a packet capture (PCAP) file (.pcap).

    You can write these packet types to a PCAP file:

    • Generated and recovered WLAN protocol packets

    • Generated and recovered 5G NR protocol packets (requires 5G Toolbox™)

    • Generated and recovered Bluetooth® low energy (BLE) link layer (LL) packets (requires Communications Toolbox™ Library for the Bluetooth Protocol)



    pcapObj = pcapWriter creates a default PCAP file writer object.


    pcapObj = pcapWriter(Name,Value) sets properties using one or more name-value pair arguments. Enclose each property name in quotes. For example, 'ByteOrder','big-endian' specifies the byte order as big-endian.


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    The pcapWriter object does not overwrite the existing PCAP file. During each call of this object, specify a unique PCAP file name.

    Name of the PCAP file, specified as a character row vector or a string scalar.

    Data Types: char | string

    Byte order, specified as 'little-endian' or 'big-endian'.

    Data Types: char | string

    Object Functions

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    writeWrite protocol packet data to PCAP or PCAPNG file
    writeGlobalHeaderWrite global header to PCAP file


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    Create a PCAP file writer object, specifying the name of the PCAP file. Specify the link type for WLAN packet.

    pcapObj = pcapWriter('FileName','writeWLANpacketdata2');
    wlanLinkType = 105;

    Write a global header to the PCAP file.


    Specify a WLAN packet.

    mpdu = 'B4000000FFFFFFFFFFFF00123456789BA79A5B28';

    Write the WLAN packet to the PCAP file.

    timestamp = 124800; % Number of microseconds


    [1] “Radiotap - Introduction.” Accessed May 20, 2020.

    [2] Group, The Tcpdump. “Tcpdump/Libpcap Public Repository.” Accessed May 20, 2020.

    [3] “Development/LibpcapFileFormat - The Wireshark Wiki.” Accessed May 20, 2020.

    Extended Capabilities

    C/C++ Code Generation

    See Also


    Introduced in R2020b