LimeSDR实验教程(5) WiFi解调

最新推荐文章于 2024-09-26 19:28:03 发布

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最新推荐文章于 2024-09-26 19:28:03 发布

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分类专栏： LimeSDR实验教程

本文链接：https://blog.youkuaiyun.com/shukebeta008/article/details/102780056

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本文介绍使用GNU Radio和USRP实现WiFi信号的接收、解调过程，以及通过软件定义无线电创建虚拟网卡进行数据包传输的方法。文中详细记录了安装流程、参数设置与调试技巧。

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这个wifi解调安装起来很简单，没什么坑，就是老外按照gnuradio不同版本也分了几个版本，我下载的是3.7版本。

先安装3.7版本的gr-foo再安装gr-ieee802-11就行。

下面的安装脚本下载的是主分支的，如果要针对3.7或者3.8的，可以在网页里直接选择对应版本下载。

或者从这里下载：

链接：https://pan.baidu.com/s/1sBmPa1X2IInwJLV4qFDa3Q
提取码：udhu

这是我下载的3.7版本的

git clone https://github.com/bastibl/gr-foo.git
cd gr-foo
mkdir build
cd build
cmake ..
make
sudo make install
sudo ldconfig

git clone git://github.com/bastibl/gr-ieee802-11.git
cd gr-ieee802-11
mkdir build
cd build
cmake ..
make
sudo make install
sudo ldconfig

还有一个问题，老外本来是用uhd模块做的收发，limesdr虽然能支持，但是很麻烦，osmocom也能用，但是噪声很多，我最后用的是gr-limesdr，把中心频率和采样率填进去就行，采样率还要填到几个滤波器带宽里去。

演示视频：https://www.bilibili.com/video/av73714958

我只实现了wifi接收和解调，能够看到我的路由器发出的星座图，并且可以把抓取的数据用wireshark分析数据包，我对比了gnuradio命令行输出的一些设备mac和路由器配置页面里的设备mac是一样的。但是发射还不行，如果用它的流图发射，我接收到的星座图很奇怪。老外还提供了一个transceiver流图，理论上可以用这个实现虚拟网卡和其他wifi设备做udp通信，但是我现在发射还不行，改天搞个usrp试试。

USRP B210发射:

https://www.bilibili.com/video/BV1UA411Y7b8/

不要装libuhd003.010.003，他现在配套的下载程序已经无法下载合适的firmware和gateware了。
要用新版的libuhd3.15.0，但是要添加ppa。
sudo add-apt-repository -y ppa:ettusresearch/uhd

sudo apt update

不要apt安装gnuradio,否则会自动安装libuhd003.010.003
从github下载gnuradio-maint-3.7 (3.7.13)然后编译安装

USRP B210 wifi虚拟网卡:

https://www.bilibili.com/video/BV1Sp4y1v7kq

电脑1运行:

sudo ifconfig tap0 down
sudo ifconfig tap0 hw ether 30:14:4a:e6:46:e4
sudo ifconfig tap0 mtu 440
sudo ifconfig tap0 up
sudo ifconfig tap0 192.168.123.2

sudo route del -net 192.168.123.0/24
sudo route add -net 192.168.123.0/24 mss 400 dev tap0

sudo tc qdisc add dev tap0 root netem delay 10ms

电脑1运行wifi_transceiver.py脚本

#!/usr/bin/env python2
# -*- coding: utf-8 -*-
##################################################
# GNU Radio Python Flow Graph
# Title: Wifi Transceiver
# GNU Radio version: 3.7.13.5
##################################################

if __name__ == '__main__':
    import ctypes
    import sys
    if sys.platform.startswith('linux'):
        try:
            x11 = ctypes.cdll.LoadLibrary('libX11.so')
            x11.XInitThreads()
        except:
            print "Warning: failed to XInitThreads()"

import os
import sys
sys.path.append(os.environ.get('GRC_HIER_PATH', os.path.expanduser('~/.grc_gnuradio')))

from PyQt4 import Qt
from PyQt4.QtCore import QObject, pyqtSlot
from gnuradio import blocks
from gnuradio import eng_notation
from gnuradio import gr
from gnuradio import qtgui
from gnuradio import uhd
from gnuradio.eng_option import eng_option
from gnuradio.filter import firdes
from gnuradio.qtgui import Range, RangeWidget
from optparse import OptionParser
from wifi_phy_hier import wifi_phy_hier  # grc-generated hier_block
import foo
import ieee802_11
import sip
import time
from gnuradio import qtgui


class wifi_transceiver(gr.top_block, Qt.QWidget):

    def __init__(self):
        gr.top_block.__init__(self, "Wifi Transceiver")
        Qt.QWidget.__init__(self)
        self.setWindowTitle("Wifi Transceiver")
        qtgui.util.check_set_qss()
        try:
            self.setWindowIcon(Qt.QIcon.fromTheme('gnuradio-grc'))
        except:
            pass
        self.top_scroll_layout = Qt.QVBoxLayout()
        self.setLayout(self.top_scroll_layout)
        self.top_scroll = Qt.QScrollArea()
        self.top_scroll.setFrameStyle(Qt.QFrame.NoFrame)
        self.top_scroll_layout.addWidget(self.top_scroll)
        self.top_scroll.setWidgetResizable(True)
        self.top_widget = Qt.QWidget()
        self.top_scroll.setWidget(self.top_widget)
        self.top_layout = Qt.QVBoxLayout(self.top_widget)
        self.top_grid_layout = Qt.QGridLayout()
        self.top_layout.addLayout(self.top_grid_layout)

        self.settings = Qt.QSettings("GNU Radio", "wifi_transceiver")
        self.restoreGeometry(self.settings.value("geometry").toByteArray())


        ##################################################
        # Variables
        ##################################################
        self.tx_gain = tx_gain = 0.75
        self.samp_rate = samp_rate = 5e6
        self.rx_gain = rx_gain = 0.75
        self.lo_offset = lo_offset = 0
        self.freq = freq = 5890000000
        self.encoding = encoding = 0
        self.chan_est = chan_est = 0

        ##################################################
        # Blocks
        ##################################################
        self._tx_gain_range = Range(0, 1, 0.01, 0.75, 200)
        self._tx_gain_win = RangeWidget(self._tx_gain_range, self.set_tx_gain, "tx_gain", "counter_slider", float)
        self.top_grid_layout.addWidget(self._tx_gain_win)
        self._samp_rate_options = [5e6, 10e6, 20e6]
        self._samp_rate_labels = ["5 MHz", "10 MHz", "20 MHz"]
        self._samp_rate_tool_bar = Qt.QToolBar(self)
        self._samp_rate_tool_bar.addWidget(Qt.QLabel("samp_rate"+": "))
        self._samp_rate_combo_box = Qt.QComboBox()
        self._samp_rate_tool_bar.addWidget(self._samp_rate_combo_box)
        for label in self._samp_rate_labels: self._samp_rate_combo_box.addItem(label)
        self._samp_rate_callback = lambda i: Qt.QMetaObject.invokeMethod(self._samp_rate_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._samp_rate_options.index(i)))
        self._samp_rate_callback(self.samp_rate)
        self._samp_rate_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_samp_rate(self._samp_rate_options[i]))
        self.top_grid_layout.addWidget(self._samp_rate_tool_bar)
        self._rx_gain_range = Range(0, 1, 0.01, 0.75, 200)
        self._rx_gain_win = RangeWidget(self._rx_gain_range, self.set_rx_gain, "rx_gain", "counter_slider", float)
        self.top_grid_layout.addWidget(self._rx_gain_win)
        self._lo_offset_options = (0, 6e6, 11e6, )
        self._lo_offset_labels = (str(self._lo_offset_options[0]), str(self._lo_offset_options[1]), str(self._lo_offset_options[2]), )
        self._lo_offset_tool_bar = Qt.QToolBar(self)
        self._lo_offset_tool_bar.addWidget(Qt.QLabel("lo_offset"+": "))
        self._lo_offset_combo_box = Qt.QComboBox()
        self._lo_offset_tool_bar.addWidget(self._lo_offset_combo_box)
        for label in self._lo_offset_labels: self._lo_offset_combo_box.addItem(label)
        self._lo_offset_callback = lambda i: Qt.QMetaObject.invokeMethod(self._lo_offset_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._lo_offset_options.index(i)))
        self._lo_offset_callback(self.lo_offset)
        self._lo_offset_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_lo_offset(self._lo_offset_options[i]))
        self.top_grid_layout.addWidget(self._lo_offset_tool_bar)
        self._freq_options = [2412000000.0, 2417000000.0, 2422000000.0, 2427000000.0, 2432000000.0, 2437000000.0, 2442000000.0, 2447000000.0, 2452000000.0, 2457000000.0, 2462000000.0, 2467000000.0, 2472000000.0, 2484000000.0, 5170000000.0, 5180000000.0, 5190000000.0, 5200000000.0, 5210000000.0, 5220000000.0, 5230000000.0, 5240000000.0, 5250000000.0, 5260000000.0, 5270000000.0, 5280000000.0, 5290000000.0, 5300000000.0, 5310000000.0, 5320000000.0, 5500000000.0, 5510000000.0, 5520000000.0, 5530000000.0, 5540000000.0, 5550000000.0, 5560000000.0, 5570000000.0, 5580000000.0, 5590000000.0, 5600000000.0, 5610000000.0, 5620000000.0, 5630000000.0, 5640000000.0, 5660000000.0, 5670000000.0, 5680000000.0, 5690000000.0, 5700000000.0, 5710000000.0, 5720000000.0, 5745000000.0, 5755000000.0, 5765000000.0, 5775000000.0, 5785000000.0, 5795000000.0, 5805000000.0, 5825000000.0, 5860000000.0, 5870000000.0, 5880000000.0, 5890000000.0, 5900000000.0, 5910000000.0, 5920000000.0]
        self._freq_labels = ['  1 | 2412.0 | 11g', '  2 | 2417.0 | 11g', '  3 | 2422.0 | 11g', '  4 | 2427.0 | 11g', '  5 | 2432.0 | 11g', '  6 | 2437.0 | 11g', '  7 | 2442.0 | 11g', '  8 | 2447.0 | 11g', '  9 | 2452.0 | 11g', ' 10 | 2457.0 | 11g', ' 11 | 2462.0 | 11g', ' 12 | 2467.0 | 11g', ' 13 | 2472.0 | 11g', ' 14 | 2484.0 | 11g', ' 34 | 5170.0 | 11a', ' 36 | 5180.0 | 11a', ' 38 | 5190.0 | 11a', ' 40 | 5200.0 | 11a', ' 42 | 5210.0 | 11a', ' 44 | 5220.0 | 11a', ' 46 | 5230.0 | 11a', ' 48 | 5240.0 | 11a', ' 50 | 5250.0 | 11a', ' 52 | 5260.0 | 11a', ' 54 | 5270.0 | 11a', ' 56 | 5280.0 | 11a', ' 58 | 5290.0 | 11a', ' 60 | 5300.0 | 11a', ' 62 | 5310.0 | 11a', ' 64 | 5320.0 | 11a', '100 | 5500.0 | 11a', '102 | 5510.0 | 11a', '104 | 5520.0 | 11a', '106 | 5530.0 | 11a', '108 | 5540.0 | 11a', '110 | 5550.0 | 11a', '112 | 5560.0 | 11a', '114 | 5570.0 | 11a', '116 | 5580.0 | 11a', '118 | 5590.0 | 11a', '120 | 5600.0 | 11a', '122 | 5610.0 | 11a', '124 | 5620.0 | 11a', '126 | 5630.0 | 11a', '128 | 5640.0 | 11a', '132 | 5660.0 | 11a', '134 | 5670.0 | 11a', '136 | 5680.0 | 11a', '138 | 5690.0 | 11a', '140 | 5700.0 | 11a', '142 | 5710.0 | 11a', '144 | 5720.0 | 11a', '149 | 5745.0 | 11a (SRD)', '151 | 5755.0 | 11a (SRD)', '153 | 5765.0 | 11a (SRD)', '155 | 5775.0 | 11a (SRD)', '157 | 5785.0 | 11a (SRD)', '159 | 5795.0 | 11a (SRD)', '161 | 5805.0 | 11a (SRD)', '165 | 5825.0 | 11a (SRD)', '172 | 5860.0 | 11p', '174 | 5870.0 | 11p', '176 | 5880.0 | 11p', '178 | 5890.0 | 11p', '180 | 5900.0 | 11p', '182 | 5910.0 | 11p', '184 | 5920.0 | 11p']
        self._freq_tool_bar = Qt.QToolBar(self)
        self._freq_tool_bar.addWidget(Qt.QLabel("freq"+": "))
        self._freq_combo_box = Qt.QComboBox()
        self._freq_tool_bar.addWidget(self._freq_combo_box)
        for label in self._freq_labels: self._freq_combo_box.addItem(label)
        self._freq_callback = lambda i: Qt.QMetaObject.invokeMethod(self._freq_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._freq_options.index(i)))
        self._freq_callback(self.freq)
        self._freq_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_freq(self._freq_options[i]))
        self.top_grid_layout.addWidget(self._freq_tool_bar)
        self._encoding_options = [0, 1, 2, 3, 4, 5, 6, 7]
        self._encoding_labels = ["BPSK 1/2", "BPSK 3/4", "QPSK 1/2", "QPSK 3/4", "16QAM 1/2", "16QAM 3/4", "64QAM 2/3", "64QAM 3/4"]
        self._encoding_group_box = Qt.QGroupBox("encoding")
        self._encoding_box = Qt.QHBoxLayout()
        class variable_chooser_button_group(Qt.QButtonGroup):
            def __init__(self, parent=None):
                Qt.QButtonGroup.__init__(self, parent)
            @pyqtSlot(int)
            def updateButtonChecked(self, button_id):
                self.button(button_id).setChecked(True)
        self._encoding_button_group = variable_chooser_button_group()
        self._encoding_group_box.setLayout(self._encoding_box)
        for i, label in enumerate(self._encoding_labels):
        	radio_button = Qt.QRadioButton(label)
        	self._encoding_box.addWidget(radio_button)
        	self._encoding_button_group.addButton(radio_button, i)
        self._encoding_callback = lambda i: Qt.QMetaObject.invokeMethod(self._encoding_button_group, "updateButtonChecked", Qt.Q_ARG("int", self._encoding_options.index(i)))
        self._encoding_callback(self.encoding)
        self._encoding_button_group.buttonClicked[int].connect(
        	lambda i: self.set_encoding(self._encoding_options[i]))
        self.top_grid_layout.addWidget(self._encoding_group_box)
        self._chan_est_options = [ieee802_11.LS, ieee802_11.LMS, ieee802_11.STA, ieee802_11.COMB]
        self._chan_est_labels = ["LS", "LMS", "STA", "Linear Comb"]
        self._chan_est_group_box = Qt.QGroupBox("chan_est")
        self._chan_est_box = Qt.QHBoxLayout()
        class variable_chooser_button_group(Qt.QButtonGroup):
            def __init__(self, parent=None):
                Qt.QButtonGroup.__init__(self, parent)
            @pyqtSlot(int)
            def updateButtonChecked(self, button_id):
                self.button(button_id).setChecked(True)
        self._chan_est_button_group = variable_chooser_button_group()
        self._chan_est_group_box.setLayout(self._chan_est_box)
        for i, label in enumerate(self._chan_est_labels):
        	radio_button = Qt.QRadioButton(label)
        	self._chan_est_box.addWidget(radio_button)
        	self._chan_est_button_group.addButton(radio_button, i)
        self._chan_est_callback = lambda i: Qt.QMetaObject.invokeMethod(self._chan_est_button_group, "updateButtonChecked", Qt.Q_ARG("int", self._chan_est_options.index(i)))
        self._chan_est_callback(self.chan_est)
        self._chan_est_button_group.buttonClicked[int].connect(
        	lambda i: self.set_chan_est(self._chan_est_options[i]))
        self.top_grid_layout.addWidget(self._chan_est_group_box)
        self.wifi_phy_hier_0 = wifi_phy_hier(
            bandwidth=samp_rate,
            chan_est=chan_est,
            encoding=encoding,
            frequency=freq,
            sensitivity=0.56,
        )
        self.uhd_usrp_source_0 = uhd.usrp_source(
        	",".join(('', "")),
        	uhd.stream_args(
        		cpu_format="fc32",
        		channels=range(1),
        	),
        )
        self.uhd_usrp_source_0.set_samp_rate(samp_rate)
        self.uhd_usrp_source_0.set_time_now(uhd.time_spec(time.time()), uhd.ALL_MBOARDS)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(freq, rf_freq = freq - lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_source_0.set_normalized_gain(rx_gain, 0)
        #self.uhd_usrp_source_0.set_auto_dc_offset("", 0)
        #self.uhd_usrp_source_0.set_auto_iq_balance("", 0)
        self.uhd_usrp_sink_0 = uhd.usrp_sink(
        	",".join(('', "")),
        	uhd.stream_args(
        		cpu_format="fc32",
        		channels=range(1),
        	),
        	'packet_len',
        )
        self.uhd_usrp_sink_0.set_samp_rate(samp_rate)
        self.uhd_usrp_sink_0.set_time_now(uhd.time_spec(time.time()), uhd.ALL_MBOARDS)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(freq, rf_freq = freq - lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_normalized_gain(tx_gain, 0)
        self.qtgui_const_sink_x_0 = qtgui.const_sink_c(
        	48*10, #size
        	"", #name
        	1 #number of inputs
        )
        self.qtgui_const_sink_x_0.set_update_time(0.10)
        self.qtgui_const_sink_x_0.set_y_axis(-2, 2)
        self.qtgui_const_sink_x_0.set_x_axis(-2, 2)
        self.qtgui_const_sink_x_0.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, "")
        self.qtgui_const_sink_x_0.enable_autoscale(False)
        self.qtgui_const_sink_x_0.enable_grid(False)
        self.qtgui_const_sink_x_0.enable_axis_labels(True)

        if not True:
          self.qtgui_const_sink_x_0.disable_legend()

        labels = ['', '', '', '', '',
                  '', '', '', '', '']
        widths = [1, 1, 1, 1, 1,
                  1, 1, 1, 1, 1]
        colors = ["blue", "red", "red", "red", "red",
                  "red", "red", "red", "red", "red"]
        styles = [0, 0, 0, 0, 0,
                  0, 0, 0, 0, 0]
        markers = [0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0]
        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
                  1.0, 1.0, 1.0, 1.0, 1.0]
        for i in xrange(1):
            if len(labels[i]) == 0:
                self.qtgui_const_sink_x_0.set_line_label(i, "Data {0}".format(i))
            else:
                self.qtgui_const_sink_x_0.set_line_label(i, labels[i])
            self.qtgui_const_sink_x_0.set_line_width(i, widths[i])
            self.qtgui_const_sink_x_0.set_line_color(i, colors[i])
            self.qtgui_const_sink_x_0.set_line_style(i, styles[i])
            self.qtgui_const_sink_x_0.set_line_marker(i, markers[i])
            self.qtgui_const_sink_x_0.set_line_alpha(i, alphas[i])

        self._qtgui_const_sink_x_0_win = sip.wrapinstance(self.qtgui_const_sink_x_0.pyqwidget(), Qt.QWidget)
        self.top_grid_layout.addWidget(self._qtgui_const_sink_x_0_win)
        self.ieee802_11_parse_mac_0 = ieee802_11.parse_mac(False, True)
        self.ieee802_11_mac_0 = ieee802_11.mac(([0x30, 0x14, 0x4a, 0xe6, 0x46, 0xe4]), ([0x12, 0x34, 0x56, 0x78, 0x90, 0xab]), ([0x42, 0x42, 0x42, 0x42, 0x42, 0x42]))
        self.ieee802_11_ether_encap_0 = ieee802_11.ether_encap(False)
        self.foo_packet_pad2_0 = foo.packet_pad2(False, False, 0.001, 10000, 10000)
        (self.foo_packet_pad2_0).set_min_output_buffer(100000)
        self.blocks_tuntap_pdu_0 = blocks.tuntap_pdu('tap0', 440, False)
        self.blocks_pdu_to_tagged_stream_0_0 = blocks.pdu_to_tagged_stream(blocks.complex_t, 'packet_len')
        self.blocks_multiply_const_vxx_0 = blocks.multiply_const_vcc((0.6, ))
        (self.blocks_multiply_const_vxx_0).set_min_output_buffer(100000)



        ##################################################
        # Connections
        ##################################################
        self.msg_connect((self.blocks_tuntap_pdu_0, 'pdus'), (self.ieee802_11_ether_encap_0, 'from tap'))
        self.msg_connect((self.ieee802_11_ether_encap_0, 'to tap'), (self.blocks_tuntap_pdu_0, 'pdus'))
        self.msg_connect((self.ieee802_11_ether_encap_0, 'to wifi'), (self.ieee802_11_mac_0, 'app in'))
        self.msg_connect((self.ieee802_11_mac_0, 'phy out'), (self.wifi_phy_hier_0, 'mac_in'))
        self.msg_connect((self.wifi_phy_hier_0, 'carrier'), (self.blocks_pdu_to_tagged_stream_0_0, 'pdus'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_ether_encap_0, 'from wifi'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_mac_0, 'phy in'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_parse_mac_0, 'in'))
        self.connect((self.blocks_multiply_const_vxx_0, 0), (self.foo_packet_pad2_0, 0))
        self.connect((self.blocks_pdu_to_tagged_stream_0_0, 0), (self.qtgui_const_sink_x_0, 0))
        self.connect((self.foo_packet_pad2_0, 0), (self.uhd_usrp_sink_0, 0))
        self.connect((self.uhd_usrp_source_0, 0), (self.wifi_phy_hier_0, 0))
        self.connect((self.wifi_phy_hier_0, 0), (self.blocks_multiply_const_vxx_0, 0))

    def closeEvent(self, event):
        self.settings = Qt.QSettings("GNU Radio", "wifi_transceiver")
        self.settings.setValue("geometry", self.saveGeometry())
        event.accept()

    def get_tx_gain(self):
        return self.tx_gain

    def set_tx_gain(self, tx_gain):
        self.tx_gain = tx_gain
        self.uhd_usrp_sink_0.set_normalized_gain(self.tx_gain, 0)


    def get_samp_rate(self):
        return self.samp_rate

    def set_samp_rate(self, samp_rate):
        self.samp_rate = samp_rate
        self._samp_rate_callback(self.samp_rate)
        self.wifi_phy_hier_0.set_bandwidth(self.samp_rate)
        self.uhd_usrp_source_0.set_samp_rate(self.samp_rate)
        self.uhd_usrp_sink_0.set_samp_rate(self.samp_rate)

    def get_rx_gain(self):
        return self.rx_gain

    def set_rx_gain(self, rx_gain):
        self.rx_gain = rx_gain
        self.uhd_usrp_source_0.set_normalized_gain(self.rx_gain, 0)


    def get_lo_offset(self):
        return self.lo_offset

    def set_lo_offset(self, lo_offset):
        self.lo_offset = lo_offset
        self._lo_offset_callback(self.lo_offset)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)

    def get_freq(self):
        return self.freq

    def set_freq(self, freq):
        self.freq = freq
        self._freq_callback(self.freq)
        self.wifi_phy_hier_0.set_frequency(self.freq)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)

    def get_encoding(self):
        return self.encoding

    def set_encoding(self, encoding):
        self.encoding = encoding
        self._encoding_callback(self.encoding)
        self.wifi_phy_hier_0.set_encoding(self.encoding)

    def get_chan_est(self):
        return self.chan_est

    def set_chan_est(self, chan_est):
        self.chan_est = chan_est
        self._chan_est_callback(self.chan_est)
        self.wifi_phy_hier_0.set_chan_est(self.chan_est)


def main(top_block_cls=wifi_transceiver, options=None):

    from distutils.version import StrictVersion
    if StrictVersion(Qt.qVersion()) >= StrictVersion("4.5.0"):
        style = gr.prefs().get_string('qtgui', 'style', 'raster')
        Qt.QApplication.setGraphicsSystem(style)
    qapp = Qt.QApplication(sys.argv)

    tb = top_block_cls()
    tb.start()
    tb.show()

    def quitting():
        tb.stop()
        tb.wait()
    qapp.connect(qapp, Qt.SIGNAL("aboutToQuit()"), quitting)
    qapp.exec_()


if __name__ == '__main__':
    main()

最后，电脑1命令行再运行：

sudo arp -s 192.168.123.1 12:34:56:78:90:ab

电脑2命令行运行:

sudo ifconfig tap0 down
sudo ifconfig tap0 hw ether 12:34:56:78:90:ab
sudo ifconfig tap0 mtu 440
sudo ifconfig tap0 up
sudo ifconfig tap0 192.168.123.1

sudo route del -net 192.168.123.0/24
sudo route add -net 192.168.123.0/24 mss 400 dev tap0

sudo tc qdisc del dev tap0 root
sudo tc qdisc add dev tap0 root netem delay 10ms

电脑2运行wifi_transceiver.py脚本

#!/usr/bin/env python2
# -*- coding: utf-8 -*-
##################################################
# GNU Radio Python Flow Graph
# Title: Wifi Transceiver
# GNU Radio version: 3.7.13.5
##################################################

if __name__ == '__main__':
    import ctypes
    import sys
    if sys.platform.startswith('linux'):
        try:
            x11 = ctypes.cdll.LoadLibrary('libX11.so')
            x11.XInitThreads()
        except:
            print "Warning: failed to XInitThreads()"

import os
import sys
sys.path.append(os.environ.get('GRC_HIER_PATH', os.path.expanduser('~/.grc_gnuradio')))

from PyQt4 import Qt
from PyQt4.QtCore import QObject, pyqtSlot
from gnuradio import blocks
from gnuradio import eng_notation
from gnuradio import gr
from gnuradio import qtgui
from gnuradio import uhd
from gnuradio.eng_option import eng_option
from gnuradio.filter import firdes
from gnuradio.qtgui import Range, RangeWidget
from optparse import OptionParser
from wifi_phy_hier import wifi_phy_hier  # grc-generated hier_block
import foo
import ieee802_11
import sip
import time
from gnuradio import qtgui


class wifi_transceiver(gr.top_block, Qt.QWidget):

    def __init__(self):
        gr.top_block.__init__(self, "Wifi Transceiver")
        Qt.QWidget.__init__(self)
        self.setWindowTitle("Wifi Transceiver")
        qtgui.util.check_set_qss()
        try:
            self.setWindowIcon(Qt.QIcon.fromTheme('gnuradio-grc'))
        except:
            pass
        self.top_scroll_layout = Qt.QVBoxLayout()
        self.setLayout(self.top_scroll_layout)
        self.top_scroll = Qt.QScrollArea()
        self.top_scroll.setFrameStyle(Qt.QFrame.NoFrame)
        self.top_scroll_layout.addWidget(self.top_scroll)
        self.top_scroll.setWidgetResizable(True)
        self.top_widget = Qt.QWidget()
        self.top_scroll.setWidget(self.top_widget)
        self.top_layout = Qt.QVBoxLayout(self.top_widget)
        self.top_grid_layout = Qt.QGridLayout()
        self.top_layout.addLayout(self.top_grid_layout)

        self.settings = Qt.QSettings("GNU Radio", "wifi_transceiver")
        self.restoreGeometry(self.settings.value("geometry").toByteArray())


        ##################################################
        # Variables
        ##################################################
        self.tx_gain = tx_gain = 0.75
        self.samp_rate = samp_rate = 5e6
        self.rx_gain = rx_gain = 0.75
        self.lo_offset = lo_offset = 0
        self.freq = freq = 5890000000
        self.encoding = encoding = 0
        self.chan_est = chan_est = 0

        ##################################################
        # Blocks
        ##################################################
        self._tx_gain_range = Range(0, 1, 0.01, 0.75, 200)
        self._tx_gain_win = RangeWidget(self._tx_gain_range, self.set_tx_gain, "tx_gain", "counter_slider", float)
        self.top_grid_layout.addWidget(self._tx_gain_win)
        self._samp_rate_options = [5e6, 10e6, 20e6]
        self._samp_rate_labels = ["5 MHz", "10 MHz", "20 MHz"]
        self._samp_rate_tool_bar = Qt.QToolBar(self)
        self._samp_rate_tool_bar.addWidget(Qt.QLabel("samp_rate"+": "))
        self._samp_rate_combo_box = Qt.QComboBox()
        self._samp_rate_tool_bar.addWidget(self._samp_rate_combo_box)
        for label in self._samp_rate_labels: self._samp_rate_combo_box.addItem(label)
        self._samp_rate_callback = lambda i: Qt.QMetaObject.invokeMethod(self._samp_rate_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._samp_rate_options.index(i)))
        self._samp_rate_callback(self.samp_rate)
        self._samp_rate_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_samp_rate(self._samp_rate_options[i]))
        self.top_grid_layout.addWidget(self._samp_rate_tool_bar)
        self._rx_gain_range = Range(0, 1, 0.01, 0.75, 200)
        self._rx_gain_win = RangeWidget(self._rx_gain_range, self.set_rx_gain, "rx_gain", "counter_slider", float)
        self.top_grid_layout.addWidget(self._rx_gain_win)
        self._lo_offset_options = (0, 6e6, 11e6, )
        self._lo_offset_labels = (str(self._lo_offset_options[0]), str(self._lo_offset_options[1]), str(self._lo_offset_options[2]), )
        self._lo_offset_tool_bar = Qt.QToolBar(self)
        self._lo_offset_tool_bar.addWidget(Qt.QLabel("lo_offset"+": "))
        self._lo_offset_combo_box = Qt.QComboBox()
        self._lo_offset_tool_bar.addWidget(self._lo_offset_combo_box)
        for label in self._lo_offset_labels: self._lo_offset_combo_box.addItem(label)
        self._lo_offset_callback = lambda i: Qt.QMetaObject.invokeMethod(self._lo_offset_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._lo_offset_options.index(i)))
        self._lo_offset_callback(self.lo_offset)
        self._lo_offset_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_lo_offset(self._lo_offset_options[i]))
        self.top_grid_layout.addWidget(self._lo_offset_tool_bar)
        self._freq_options = [2412000000.0, 2417000000.0, 2422000000.0, 2427000000.0, 2432000000.0, 2437000000.0, 2442000000.0, 2447000000.0, 2452000000.0, 2457000000.0, 2462000000.0, 2467000000.0, 2472000000.0, 2484000000.0, 5170000000.0, 5180000000.0, 5190000000.0, 5200000000.0, 5210000000.0, 5220000000.0, 5230000000.0, 5240000000.0, 5250000000.0, 5260000000.0, 5270000000.0, 5280000000.0, 5290000000.0, 5300000000.0, 5310000000.0, 5320000000.0, 5500000000.0, 5510000000.0, 5520000000.0, 5530000000.0, 5540000000.0, 5550000000.0, 5560000000.0, 5570000000.0, 5580000000.0, 5590000000.0, 5600000000.0, 5610000000.0, 5620000000.0, 5630000000.0, 5640000000.0, 5660000000.0, 5670000000.0, 5680000000.0, 5690000000.0, 5700000000.0, 5710000000.0, 5720000000.0, 5745000000.0, 5755000000.0, 5765000000.0, 5775000000.0, 5785000000.0, 5795000000.0, 5805000000.0, 5825000000.0, 5860000000.0, 5870000000.0, 5880000000.0, 5890000000.0, 5900000000.0, 5910000000.0, 5920000000.0]
        self._freq_labels = ['  1 | 2412.0 | 11g', '  2 | 2417.0 | 11g', '  3 | 2422.0 | 11g', '  4 | 2427.0 | 11g', '  5 | 2432.0 | 11g', '  6 | 2437.0 | 11g', '  7 | 2442.0 | 11g', '  8 | 2447.0 | 11g', '  9 | 2452.0 | 11g', ' 10 | 2457.0 | 11g', ' 11 | 2462.0 | 11g', ' 12 | 2467.0 | 11g', ' 13 | 2472.0 | 11g', ' 14 | 2484.0 | 11g', ' 34 | 5170.0 | 11a', ' 36 | 5180.0 | 11a', ' 38 | 5190.0 | 11a', ' 40 | 5200.0 | 11a', ' 42 | 5210.0 | 11a', ' 44 | 5220.0 | 11a', ' 46 | 5230.0 | 11a', ' 48 | 5240.0 | 11a', ' 50 | 5250.0 | 11a', ' 52 | 5260.0 | 11a', ' 54 | 5270.0 | 11a', ' 56 | 5280.0 | 11a', ' 58 | 5290.0 | 11a', ' 60 | 5300.0 | 11a', ' 62 | 5310.0 | 11a', ' 64 | 5320.0 | 11a', '100 | 5500.0 | 11a', '102 | 5510.0 | 11a', '104 | 5520.0 | 11a', '106 | 5530.0 | 11a', '108 | 5540.0 | 11a', '110 | 5550.0 | 11a', '112 | 5560.0 | 11a', '114 | 5570.0 | 11a', '116 | 5580.0 | 11a', '118 | 5590.0 | 11a', '120 | 5600.0 | 11a', '122 | 5610.0 | 11a', '124 | 5620.0 | 11a', '126 | 5630.0 | 11a', '128 | 5640.0 | 11a', '132 | 5660.0 | 11a', '134 | 5670.0 | 11a', '136 | 5680.0 | 11a', '138 | 5690.0 | 11a', '140 | 5700.0 | 11a', '142 | 5710.0 | 11a', '144 | 5720.0 | 11a', '149 | 5745.0 | 11a (SRD)', '151 | 5755.0 | 11a (SRD)', '153 | 5765.0 | 11a (SRD)', '155 | 5775.0 | 11a (SRD)', '157 | 5785.0 | 11a (SRD)', '159 | 5795.0 | 11a (SRD)', '161 | 5805.0 | 11a (SRD)', '165 | 5825.0 | 11a (SRD)', '172 | 5860.0 | 11p', '174 | 5870.0 | 11p', '176 | 5880.0 | 11p', '178 | 5890.0 | 11p', '180 | 5900.0 | 11p', '182 | 5910.0 | 11p', '184 | 5920.0 | 11p']
        self._freq_tool_bar = Qt.QToolBar(self)
        self._freq_tool_bar.addWidget(Qt.QLabel("freq"+": "))
        self._freq_combo_box = Qt.QComboBox()
        self._freq_tool_bar.addWidget(self._freq_combo_box)
        for label in self._freq_labels: self._freq_combo_box.addItem(label)
        self._freq_callback = lambda i: Qt.QMetaObject.invokeMethod(self._freq_combo_box, "setCurrentIndex", Qt.Q_ARG("int", self._freq_options.index(i)))
        self._freq_callback(self.freq)
        self._freq_combo_box.currentIndexChanged.connect(
        	lambda i: self.set_freq(self._freq_options[i]))
        self.top_grid_layout.addWidget(self._freq_tool_bar)
        self._encoding_options = [0, 1, 2, 3, 4, 5, 6, 7]
        self._encoding_labels = ["BPSK 1/2", "BPSK 3/4", "QPSK 1/2", "QPSK 3/4", "16QAM 1/2", "16QAM 3/4", "64QAM 2/3", "64QAM 3/4"]
        self._encoding_group_box = Qt.QGroupBox("encoding")
        self._encoding_box = Qt.QHBoxLayout()
        class variable_chooser_button_group(Qt.QButtonGroup):
            def __init__(self, parent=None):
                Qt.QButtonGroup.__init__(self, parent)
            @pyqtSlot(int)
            def updateButtonChecked(self, button_id):
                self.button(button_id).setChecked(True)
        self._encoding_button_group = variable_chooser_button_group()
        self._encoding_group_box.setLayout(self._encoding_box)
        for i, label in enumerate(self._encoding_labels):
        	radio_button = Qt.QRadioButton(label)
        	self._encoding_box.addWidget(radio_button)
        	self._encoding_button_group.addButton(radio_button, i)
        self._encoding_callback = lambda i: Qt.QMetaObject.invokeMethod(self._encoding_button_group, "updateButtonChecked", Qt.Q_ARG("int", self._encoding_options.index(i)))
        self._encoding_callback(self.encoding)
        self._encoding_button_group.buttonClicked[int].connect(
        	lambda i: self.set_encoding(self._encoding_options[i]))
        self.top_grid_layout.addWidget(self._encoding_group_box)
        self._chan_est_options = [ieee802_11.LS, ieee802_11.LMS, ieee802_11.STA, ieee802_11.COMB]
        self._chan_est_labels = ["LS", "LMS", "STA", "Linear Comb"]
        self._chan_est_group_box = Qt.QGroupBox("chan_est")
        self._chan_est_box = Qt.QHBoxLayout()
        class variable_chooser_button_group(Qt.QButtonGroup):
            def __init__(self, parent=None):
                Qt.QButtonGroup.__init__(self, parent)
            @pyqtSlot(int)
            def updateButtonChecked(self, button_id):
                self.button(button_id).setChecked(True)
        self._chan_est_button_group = variable_chooser_button_group()
        self._chan_est_group_box.setLayout(self._chan_est_box)
        for i, label in enumerate(self._chan_est_labels):
        	radio_button = Qt.QRadioButton(label)
        	self._chan_est_box.addWidget(radio_button)
        	self._chan_est_button_group.addButton(radio_button, i)
        self._chan_est_callback = lambda i: Qt.QMetaObject.invokeMethod(self._chan_est_button_group, "updateButtonChecked", Qt.Q_ARG("int", self._chan_est_options.index(i)))
        self._chan_est_callback(self.chan_est)
        self._chan_est_button_group.buttonClicked[int].connect(
        	lambda i: self.set_chan_est(self._chan_est_options[i]))
        self.top_grid_layout.addWidget(self._chan_est_group_box)
        self.wifi_phy_hier_0 = wifi_phy_hier(
            bandwidth=samp_rate,
            chan_est=chan_est,
            encoding=encoding,
            frequency=freq,
            sensitivity=0.56,
        )
        self.uhd_usrp_source_0 = uhd.usrp_source(
        	",".join(('', "")),
        	uhd.stream_args(
        		cpu_format="fc32",
        		channels=range(1),
        	),
        )
        self.uhd_usrp_source_0.set_samp_rate(samp_rate)
        self.uhd_usrp_source_0.set_time_now(uhd.time_spec(time.time()), uhd.ALL_MBOARDS)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(freq, rf_freq = freq - lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_source_0.set_normalized_gain(rx_gain, 0)
        #self.uhd_usrp_source_0.set_auto_dc_offset("", 0)
        #self.uhd_usrp_source_0.set_auto_iq_balance("", 0)
        self.uhd_usrp_sink_0 = uhd.usrp_sink(
        	",".join(('', "")),
        	uhd.stream_args(
        		cpu_format="fc32",
        		channels=range(1),
        	),
        	'packet_len',
        )
        self.uhd_usrp_sink_0.set_samp_rate(samp_rate)
        self.uhd_usrp_sink_0.set_time_now(uhd.time_spec(time.time()), uhd.ALL_MBOARDS)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(freq, rf_freq = freq - lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_normalized_gain(tx_gain, 0)
        self.qtgui_const_sink_x_0 = qtgui.const_sink_c(
        	48*10, #size
        	"", #name
        	1 #number of inputs
        )
        self.qtgui_const_sink_x_0.set_update_time(0.10)
        self.qtgui_const_sink_x_0.set_y_axis(-2, 2)
        self.qtgui_const_sink_x_0.set_x_axis(-2, 2)
        self.qtgui_const_sink_x_0.set_trigger_mode(qtgui.TRIG_MODE_FREE, qtgui.TRIG_SLOPE_POS, 0.0, 0, "")
        self.qtgui_const_sink_x_0.enable_autoscale(False)
        self.qtgui_const_sink_x_0.enable_grid(False)
        self.qtgui_const_sink_x_0.enable_axis_labels(True)

        if not True:
          self.qtgui_const_sink_x_0.disable_legend()

        labels = ['', '', '', '', '',
                  '', '', '', '', '']
        widths = [1, 1, 1, 1, 1,
                  1, 1, 1, 1, 1]
        colors = ["blue", "red", "red", "red", "red",
                  "red", "red", "red", "red", "red"]
        styles = [0, 0, 0, 0, 0,
                  0, 0, 0, 0, 0]
        markers = [0, 0, 0, 0, 0,
                   0, 0, 0, 0, 0]
        alphas = [1.0, 1.0, 1.0, 1.0, 1.0,
                  1.0, 1.0, 1.0, 1.0, 1.0]
        for i in xrange(1):
            if len(labels[i]) == 0:
                self.qtgui_const_sink_x_0.set_line_label(i, "Data {0}".format(i))
            else:
                self.qtgui_const_sink_x_0.set_line_label(i, labels[i])
            self.qtgui_const_sink_x_0.set_line_width(i, widths[i])
            self.qtgui_const_sink_x_0.set_line_color(i, colors[i])
            self.qtgui_const_sink_x_0.set_line_style(i, styles[i])
            self.qtgui_const_sink_x_0.set_line_marker(i, markers[i])
            self.qtgui_const_sink_x_0.set_line_alpha(i, alphas[i])

        self._qtgui_const_sink_x_0_win = sip.wrapinstance(self.qtgui_const_sink_x_0.pyqwidget(), Qt.QWidget)
        self.top_grid_layout.addWidget(self._qtgui_const_sink_x_0_win)
        self.ieee802_11_parse_mac_0 = ieee802_11.parse_mac(False, True)
        self.ieee802_11_mac_0 = ieee802_11.mac(([0x12, 0x34, 0x56, 0x78, 0x90, 0xab]), ([0x30, 0x14, 0x4a, 0xe6, 0x46, 0xe4]), ([0x42, 0x42, 0x42, 0x42, 0x42, 0x42]))
        self.ieee802_11_ether_encap_0 = ieee802_11.ether_encap(False)
        self.foo_wireshark_connector_0 = foo.wireshark_connector(127, False)
        self.foo_packet_pad2_0 = foo.packet_pad2(False, False, 0.001, 10000, 10000)
        (self.foo_packet_pad2_0).set_min_output_buffer(100000)
        self.blocks_tuntap_pdu_0 = blocks.tuntap_pdu('tap0', 440, False)
        self.blocks_pdu_to_tagged_stream_0_0 = blocks.pdu_to_tagged_stream(blocks.complex_t, 'packet_len')
        self.blocks_multiply_const_vxx_0 = blocks.multiply_const_vcc((0.6, ))
        (self.blocks_multiply_const_vxx_0).set_min_output_buffer(100000)
        self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_char*1, '/tmp/wifi.pcap', True)
        self.blocks_file_sink_0.set_unbuffered(True)



        ##################################################
        # Connections
        ##################################################
        self.msg_connect((self.blocks_tuntap_pdu_0, 'pdus'), (self.ieee802_11_ether_encap_0, 'from tap'))
        self.msg_connect((self.ieee802_11_ether_encap_0, 'to tap'), (self.blocks_tuntap_pdu_0, 'pdus'))
        self.msg_connect((self.ieee802_11_ether_encap_0, 'to wifi'), (self.ieee802_11_mac_0, 'app in'))
        self.msg_connect((self.ieee802_11_mac_0, 'phy out'), (self.wifi_phy_hier_0, 'mac_in'))
        self.msg_connect((self.wifi_phy_hier_0, 'carrier'), (self.blocks_pdu_to_tagged_stream_0_0, 'pdus'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.foo_wireshark_connector_0, 'in'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_ether_encap_0, 'from wifi'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_mac_0, 'phy in'))
        self.msg_connect((self.wifi_phy_hier_0, 'mac_out'), (self.ieee802_11_parse_mac_0, 'in'))
        self.connect((self.blocks_multiply_const_vxx_0, 0), (self.foo_packet_pad2_0, 0))
        self.connect((self.blocks_pdu_to_tagged_stream_0_0, 0), (self.qtgui_const_sink_x_0, 0))
        self.connect((self.foo_packet_pad2_0, 0), (self.uhd_usrp_sink_0, 0))
        self.connect((self.foo_wireshark_connector_0, 0), (self.blocks_file_sink_0, 0))
        self.connect((self.uhd_usrp_source_0, 0), (self.wifi_phy_hier_0, 0))
        self.connect((self.wifi_phy_hier_0, 0), (self.blocks_multiply_const_vxx_0, 0))

    def closeEvent(self, event):
        self.settings = Qt.QSettings("GNU Radio", "wifi_transceiver")
        self.settings.setValue("geometry", self.saveGeometry())
        event.accept()

    def get_tx_gain(self):
        return self.tx_gain

    def set_tx_gain(self, tx_gain):
        self.tx_gain = tx_gain
        self.uhd_usrp_sink_0.set_normalized_gain(self.tx_gain, 0)


    def get_samp_rate(self):
        return self.samp_rate

    def set_samp_rate(self, samp_rate):
        self.samp_rate = samp_rate
        self._samp_rate_callback(self.samp_rate)
        self.wifi_phy_hier_0.set_bandwidth(self.samp_rate)
        self.uhd_usrp_source_0.set_samp_rate(self.samp_rate)
        self.uhd_usrp_sink_0.set_samp_rate(self.samp_rate)

    def get_rx_gain(self):
        return self.rx_gain

    def set_rx_gain(self, rx_gain):
        self.rx_gain = rx_gain
        self.uhd_usrp_source_0.set_normalized_gain(self.rx_gain, 0)


    def get_lo_offset(self):
        return self.lo_offset

    def set_lo_offset(self, lo_offset):
        self.lo_offset = lo_offset
        self._lo_offset_callback(self.lo_offset)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)

    def get_freq(self):
        return self.freq

    def set_freq(self, freq):
        self.freq = freq
        self._freq_callback(self.freq)
        self.wifi_phy_hier_0.set_frequency(self.freq)
        self.uhd_usrp_source_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)
        self.uhd_usrp_sink_0.set_center_freq(uhd.tune_request(self.freq, rf_freq = self.freq - self.lo_offset, rf_freq_policy=uhd.tune_request.POLICY_MANUAL), 0)

    def get_encoding(self):
        return self.encoding

    def set_encoding(self, encoding):
        self.encoding = encoding
        self._encoding_callback(self.encoding)
        self.wifi_phy_hier_0.set_encoding(self.encoding)

    def get_chan_est(self):
        return self.chan_est

    def set_chan_est(self, chan_est):
        self.chan_est = chan_est
        self._chan_est_callback(self.chan_est)
        self.wifi_phy_hier_0.set_chan_est(self.chan_est)


def main(top_block_cls=wifi_transceiver, options=None):

    from distutils.version import StrictVersion
    if StrictVersion(Qt.qVersion()) >= StrictVersion("4.5.0"):
        style = gr.prefs().get_string('qtgui', 'style', 'raster')
        Qt.QApplication.setGraphicsSystem(style)
    qapp = Qt.QApplication(sys.argv)

    tb = top_block_cls()
    tb.start()
    tb.show()

    def quitting():
        tb.stop()
        tb.wait()
    qapp.connect(qapp, Qt.SIGNAL("aboutToQuit()"), quitting)
    qapp.exec_()


if __name__ == '__main__':
    main()

最后电脑2运行：

sudo arp -s 192.168.123.2 30:14:4a:e6:46:e4

两个电脑运行的东西都差不多，主要是ip和mac不一样，另外wifi_transceiver里的dst和src的mac地址也要调换一下。

HackRF接收

如果你没有LimeSDR或者USRP这些昂贵的设备，你也可以用HackRF来接收WiFi数据包。

它的DC offset比较大，所以不能直接用wifi_rx.grc流图，而是要在osmocom source后面接一个FFT Filter实现的高通滤波器。如下图：

然后你保持采样率20MHz不变，耐心地切换各个中心频点，直到观察到类似上面的QAM图形或者2PSK图像就说明能解出数据包了。

这时回到gnuradio界面，左下角会有数据包里对应的Mac地址信息。

流图下载：

https://github.com/bastibl/gr-ieee802-11/files/6813359/wifi_rx_hackrf.zip