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wifi-simple-interference.cc
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1 /* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2009 The Boeing Company
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation;
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  *
18  */
19 
20 //
21 // This script configures three nodes on an 802.11b physical layer, with
22 // 802.11b NICs in adhoc mode. There is a transmitter, receiver, and
23 // interferer. The transmitter sends one packet to the receiver and
24 // the receiver receives it with a certain configurable RSS (by default,
25 // -80 dBm). The interferer does not do carrier sense and also sends
26 // the packet to interfere with the primary packet. The channel model
27 // is clear channel.
28 //
29 // Therefore, at the receiver, the reception looks like this:
30 //
31 // ------------------time---------------->
32 // t0
33 //
34 // |------------------------------------|
35 // | |
36 // | primary received frame (time t0) |
37 // | |
38 // |------------------------------------|
39 //
40 //
41 // t1
42 // |-----------------------------------|
43 // | |
44 // | interfering frame (time t1) |
45 // | |
46 // |-----------------------------------|
47 //
48 // The orientation is:
49 // n2 ---------> n0 <---------- n1
50 // interferer receiver transmitter
51 //
52 // The configurable parameters are:
53 // - Prss (primary rss) (-80 dBm default)
54 // - Irss (interfering rss) (-95 dBm default)
55 // - delta (microseconds, (t1-t0), may be negative, default 0)
56 // - PpacketSize (primary packet size) (bytes, default 1000)
57 // - IpacketSize (interferer packet size) (bytes, default 1000)
58 //
59 // For instance, for this configuration, the interfering frame arrives
60 // at -90 dBm with a time offset of 3.2 microseconds:
61 //
62 // ./waf --run "wifi-simple-interference --Irss=-90 --delta=3.2"
63 //
64 // Note that all ns-3 attributes (not just the ones exposed in the below
65 // script) can be changed at command line; see the documentation.
66 //
67 // This script can also be helpful to put the Wifi layer into verbose
68 // logging mode; this command will turn on all wifi logging:
69 //
70 // ./waf --run "wifi-simple-interference --verbose=1"
71 //
72 // When you are done, you will notice a pcap trace file in your directory.
73 // If you have tcpdump installed, you can try this:
74 //
75 // tcpdump -r wifi-simple-interference-0-0.pcap -nn -tt
76 // reading from file wifi-simple-interference-0-0.pcap, link-type IEEE802_11_RADIO (802.11 plus BSD radio information header)
77 // 10.008704 10008704us tsft 1.0 Mb/s 2437 MHz (0x00c0) -80dB signal -98dB noise IP 10.1.1.2.49153 > 10.1.1.255.80: UDP, length 1000
78 //
79 // Next, try this command and look at the tcpdump-- you should see two packets
80 // that are no longer interfering:
81 // ./waf --run "wifi-simple-interference --delta=30000"
82 
83 #include "ns3/core-module.h"
84 #include "ns3/network-module.h"
85 #include "ns3/mobility-module.h"
86 #include "ns3/config-store-module.h"
87 #include "ns3/wifi-module.h"
88 #include "ns3/internet-module.h"
89 
90 #include <iostream>
91 #include <fstream>
92 #include <vector>
93 #include <string>
94 
95 NS_LOG_COMPONENT_DEFINE ("WifiSimpleInterference");
96 
97 using namespace ns3;
98 
99 static inline std::string PrintReceivedPacket (Ptr<Socket> socket)
100 {
101  Address addr;
102  socket->GetSockName (addr);
104 
105  std::ostringstream oss;
106  oss << "Received one packet! Socket: " << iaddr.GetIpv4 () << " port: " << iaddr.GetPort ();
107 
108  return oss.str ();
109 }
110 
111 static void ReceivePacket (Ptr<Socket> socket)
112 {
114 }
115 
116 static void GenerateTraffic (Ptr<Socket> socket, uint32_t pktSize,
117  uint32_t pktCount, Time pktInterval )
118 {
119  if (pktCount > 0)
120  {
121  socket->Send (Create<Packet> (pktSize));
122  Simulator::Schedule (pktInterval, &GenerateTraffic,
123  socket, pktSize,pktCount-1, pktInterval);
124  }
125  else
126  {
127  socket->Close ();
128  }
129 }
130 
131 
132 int main (int argc, char *argv[])
133 {
134 // LogComponentEnable ("InterferenceHelper", LOG_LEVEL_ALL);
135 
136  std::string phyMode ("DsssRate1Mbps");
137  double Prss = -80; // -dBm
138  double Irss = -95; // -dBm
139  double delta = 0; // microseconds
140  uint32_t PpacketSize = 1000; // bytes
141  uint32_t IpacketSize = 1000; // bytes
142  bool verbose = false;
143 
144  // these are not command line arguments for this version
145  uint32_t numPackets = 1;
146  double interval = 1.0; // seconds
147  double startTime = 10.0; // seconds
148  double distanceToRx = 100.0; // meters
149 
150  double offset = 91; // This is a magic number used to set the
151  // transmit power, based on other configuration
152  CommandLine cmd;
153 
154  cmd.AddValue ("phyMode", "Wifi Phy mode", phyMode);
155  cmd.AddValue ("Prss", "Intended primary received signal strength (dBm)", Prss);
156  cmd.AddValue ("Irss", "Intended interfering received signal strength (dBm)", Irss);
157  cmd.AddValue ("delta", "time offset (microseconds) for interfering signal", delta);
158  cmd.AddValue ("PpacketSize", "size of application packet sent", PpacketSize);
159  cmd.AddValue ("IpacketSize", "size of interfering packet sent", IpacketSize);
160  cmd.AddValue ("verbose", "turn on all WifiNetDevice log components", verbose);
161 
162  cmd.Parse (argc, argv);
163  // Convert to time object
164  Time interPacketInterval = Seconds (interval);
165 
166  // disable fragmentation for frames below 2200 bytes
167  Config::SetDefault ("ns3::WifiRemoteStationManager::FragmentationThreshold", StringValue ("2200"));
168  // turn off RTS/CTS for frames below 2200 bytes
169  Config::SetDefault ("ns3::WifiRemoteStationManager::RtsCtsThreshold", StringValue ("2200"));
170  // Fix non-unicast data rate to be the same as that of unicast
171  Config::SetDefault ("ns3::WifiRemoteStationManager::NonUnicastMode",
172  StringValue (phyMode));
173 
174  NodeContainer c;
175  c.Create (3);
176 
177  // The below set of helpers will help us to put together the wifi NICs we want
178  WifiHelper wifi;
179  if (verbose)
180  {
181  wifi.EnableLogComponents (); // Turn on all Wifi logging
182  }
184 
186  // set it to zero; otherwise, gain will be added
187  wifiPhy.Set ("RxGain", DoubleValue (0) );
188  wifiPhy.Set ("CcaMode1Threshold", DoubleValue (0.0) );
189 
190  // ns-3 supports RadioTap and Prism tracing extensions for 802.11b
192 
193  YansWifiChannelHelper wifiChannel;
194  wifiChannel.SetPropagationDelay ("ns3::ConstantSpeedPropagationDelayModel");
195  wifiChannel.AddPropagationLoss ("ns3::LogDistancePropagationLossModel");
196  wifiPhy.SetChannel (wifiChannel.Create ());
197 
198  // Add a non-QoS upper mac, and disable rate control
200  wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager",
201  "DataMode",StringValue (phyMode),
202  "ControlMode",StringValue (phyMode));
203  // Set it to adhoc mode
204  wifiMac.SetType ("ns3::AdhocWifiMac");
205  NetDeviceContainer devices = wifi.Install (wifiPhy, wifiMac, c.Get (0));
206  // This will disable these sending devices from detecting a signal
207  // so that they do not backoff
208  wifiPhy.Set ("EnergyDetectionThreshold", DoubleValue (0.0) );
209  wifiPhy.Set ("TxGain", DoubleValue (offset + Prss) );
210  devices.Add (wifi.Install (wifiPhy, wifiMac, c.Get (1)));
211  wifiPhy.Set ("TxGain", DoubleValue (offset + Irss) );
212  devices.Add (wifi.Install (wifiPhy, wifiMac, c.Get (2)));
213 
214  // Note that with FixedRssLossModel, the positions below are not
215  // used for received signal strength.
216  MobilityHelper mobility;
217  Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();
218  positionAlloc->Add (Vector (0.0, 0.0, 0.0));
219  positionAlloc->Add (Vector (distanceToRx, 0.0, 0.0));
220  positionAlloc->Add (Vector (-1*distanceToRx, 0.0, 0.0));
221  mobility.SetPositionAllocator (positionAlloc);
222  mobility.SetMobilityModel ("ns3::ConstantPositionMobilityModel");
223  mobility.Install (c);
224 
225  InternetStackHelper internet;
226  internet.Install (c);
227 
228  Ipv4AddressHelper ipv4;
229  NS_LOG_INFO ("Assign IP Addresses.");
230  ipv4.SetBase ("10.1.1.0", "255.255.255.0");
231  Ipv4InterfaceContainer i = ipv4.Assign (devices);
232 
233  TypeId tid = TypeId::LookupByName ("ns3::UdpSocketFactory");
234  Ptr<Socket> recvSink = Socket::CreateSocket (c.Get (0), tid);
235  InetSocketAddress local = InetSocketAddress (Ipv4Address ("10.1.1.1"), 80);
236  recvSink->Bind (local);
238 
239  Ptr<Socket> source = Socket::CreateSocket (c.Get (1), tid);
240  InetSocketAddress remote = InetSocketAddress (Ipv4Address ("255.255.255.255"), 80);
241  source->SetAllowBroadcast (true);
242  source->Connect (remote);
243 
244  // Interferer will send to a different port; we will not see a
245  // "Received packet" message
246  Ptr<Socket> interferer = Socket::CreateSocket (c.Get (2), tid);
247  InetSocketAddress interferingAddr = InetSocketAddress (Ipv4Address ("255.255.255.255"), 49000);
248  interferer->SetAllowBroadcast (true);
249  interferer->Connect (interferingAddr);
250 
251  // Tracing
252  wifiPhy.EnablePcap ("wifi-simple-interference", devices.Get (0));
253 
254  // Output what we are doing
255  NS_LOG_UNCOND ("Primary packet RSS=" << Prss << " dBm and interferer RSS=" << Irss << " dBm at time offset=" << delta << " ms");
256 
258  Seconds (startTime), &GenerateTraffic,
259  source, PpacketSize, numPackets, interPacketInterval);
260 
261  Simulator::ScheduleWithContext (interferer->GetNode ()->GetId (),
262  Seconds (startTime + delta/1000000.0), &GenerateTraffic,
263  interferer, IpacketSize, numPackets, interPacketInterval);
264 
265  Simulator::Run ();
267 
268  return 0;
269 }
270