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wifi-interference-test-suite.cc
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1 /*
2  * Copyright (c) 2009 University of Washington
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5  * it under the terms of the GNU General Public License version 2 as
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11  * GNU General Public License for more details.
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15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16  */
17 
18 #include <iostream>
19 #include <fstream>
20 #include <vector>
21 #include <string>
22 
23 #include "ns3/log.h"
24 #include "ns3/callback.h"
25 #include "ns3/abort.h"
26 #include "ns3/test.h"
27 #include "ns3/pcap-file.h"
28 #include "ns3/config.h"
29 #include "ns3/string.h"
30 #include "ns3/uinteger.h"
31 #include "ns3/double.h"
32 #include "ns3/data-rate.h"
33 #include "ns3/inet-socket-address.h"
34 #include "ns3/internet-stack-helper.h"
35 #include "ns3/ipv4-address-helper.h"
36 #include "ns3/tcp-socket-factory.h"
37 #include "ns3/yans-wifi-helper.h"
38 #include "ns3/propagation-loss-model.h"
39 #include "ns3/propagation-delay-model.h"
40 #include "ns3/yans-wifi-channel.h"
41 #include "ns3/yans-wifi-phy.h"
42 #include "ns3/wifi-net-device.h"
43 #include "ns3/mobility-helper.h"
44 #include "ns3/constant-position-mobility-model.h"
45 #include "ns3/nqos-wifi-mac-helper.h"
46 #include "ns3/simulator.h"
47 
48 NS_LOG_COMPONENT_DEFINE ("WifiInterferenceTestSuite");
49 
50 using namespace ns3;
51 
52 class WifiInterferenceTestCase : public TestCase
53 {
54 public:
55  WifiInterferenceTestCase ();
56  virtual ~WifiInterferenceTestCase ();
57 
58 private:
59  virtual void DoRun (void);
60  void ReceivePacket (Ptr<Socket> socket);
61  static void GenerateTraffic (Ptr<Socket> socket, uint32_t pktSize, uint32_t pktCount, Time pktInterval);
62  void PrintEndSync (std::string context, uint32_t dataRate, double snr, double per);
63  double WifiSimpleInterference (std::string phyMode, double Prss, double Irss, double delta, uint32_t PpacketSize,
64  uint32_t IpacketSize, bool verbose, InternetStackHelper internet);
65  double m_PER;
66  double m_SNR;
67  uint32_t m_DataRate;
68 };
69 
70 // Add some help text to this case to describe what it is intended to test
71 WifiInterferenceTestCase::WifiInterferenceTestCase ()
72  : TestCase ("Test interference calculation when interfering frame exactly overlaps intended frame")
73 {
74 }
75 
76 WifiInterferenceTestCase::~WifiInterferenceTestCase ()
77 {
78 }
79 
80 static inline std::string
81 PrintReceivedPacket (Ptr<Socket> socket)
82 {
83  Address addr;
84  socket->GetSockName (addr);
85  InetSocketAddress iaddr = InetSocketAddress::ConvertFrom (addr);
86 
87  std::ostringstream oss;
88  oss << "Received one packet! Socket: " << iaddr.GetIpv4 () << " port: " << iaddr.GetPort ();
89 
90  return oss.str ();
91 }
92 
93 void
94 WifiInterferenceTestCase::ReceivePacket (Ptr<Socket> socket)
95 {
96  NS_LOG_UNCOND (PrintReceivedPacket (socket));
97 }
98 
99 void
100 WifiInterferenceTestCase::GenerateTraffic (Ptr<Socket> socket, uint32_t pktSize, uint32_t pktCount, Time pktInterval)
101 {
102  if (pktCount > 0)
103  {
104  socket->Send (Create<Packet> (pktSize));
105  Simulator::Schedule (pktInterval, &WifiInterferenceTestCase::GenerateTraffic, socket, pktSize, pktCount-1, pktInterval);
106  }
107  else
108  {
109  socket->Close ();
110  }
111 }
112 
113 void
114 WifiInterferenceTestCase::PrintEndSync (std::string context, uint32_t dataRate, double snr, double per)
115 {
116  NS_LOG_UNCOND ("EndSync: Received frame with dataRate=" << dataRate << ", SNR=" << snr << ", PER =" << per);
117  m_PER = per;
118  m_SNR = snr;
119  m_DataRate = dataRate;
120 }
121 
122 double
123 WifiInterferenceTestCase::WifiSimpleInterference (std::string phyMode,double Prss, double Irss, double delta, uint32_t PpacketSize, uint32_t IpacketSize, bool verbose, InternetStackHelper internet)
124 {
125 
126  uint32_t numPackets = 1;
127  double interval = 1.0; // seconds
128  double startTime = 10.0; // seconds
129  double distanceToRx = 100.0; // meters
130 
131  double offset = 91; // This is a magic number used to set the
132  // transmit power, based on other configuration
133 
134  m_PER = 0;
135  m_SNR = 0;
136  m_DataRate = 0;
137 
138  // Convert to time object
139  Time interPacketInterval = Seconds (interval);
140 
141  // disable fragmentation for frames below 2200 bytes
142  Config::SetDefault ("ns3::WifiRemoteStationManager::FragmentationThreshold", StringValue ("2200"));
143  // turn off RTS/CTS for frames below 2200 bytes
144  Config::SetDefault ("ns3::WifiRemoteStationManager::RtsCtsThreshold", StringValue ("2200"));
145  // Fix non-unicast data rate to be the same as that of unicast
146  Config::SetDefault ("ns3::WifiRemoteStationManager::NonUnicastMode",
147  StringValue (phyMode));
148 
149  NodeContainer c;
150  c.Create (3);
151 
152  // The below set of helpers will help us to put together the wifi NICs we want
153  WifiHelper wifi;
154  wifi.SetStandard (WIFI_PHY_STANDARD_80211b);
155 
156  YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default ();
157  // This is one parameter that matters when using FixedRssLossModel
158  // set it to zero; otherwise, gain will be added
159  wifiPhy.Set ("RxGain", DoubleValue (0) );
160  wifiPhy.Set ("CcaMode1Threshold", DoubleValue (0.0) );
161 
162  // ns-3 supports RadioTap and Prism tracing extensions for 802.11b
163  wifiPhy.SetPcapDataLinkType (YansWifiPhyHelper::DLT_IEEE802_11_RADIO);
164 
165  YansWifiChannelHelper wifiChannel;
166  wifiChannel.SetPropagationDelay ("ns3::ConstantSpeedPropagationDelayModel");
167  wifiChannel.AddPropagationLoss ("ns3::LogDistancePropagationLossModel");
168  wifiPhy.SetChannel (wifiChannel.Create ());
169 
170  // Add a non-QoS upper mac, and disable rate control
171  NqosWifiMacHelper wifiMac = NqosWifiMacHelper::Default ();
172  wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager",
173  "DataMode",StringValue (phyMode),
174  "ControlMode",StringValue (phyMode));
175  // Set it to adhoc mode
176  wifiMac.SetType ("ns3::AdhocWifiMac");
177  NetDeviceContainer devices = wifi.Install (wifiPhy, wifiMac, c.Get (0));
178  // This will disable these sending devices from detecting a signal
179  // so that they do not backoff
180  wifiPhy.Set ("EnergyDetectionThreshold", DoubleValue (0.0) );
181  wifiPhy.Set ("TxGain", DoubleValue (offset + Prss) );
182  devices.Add (wifi.Install (wifiPhy, wifiMac, c.Get (1)));
183  wifiPhy.Set ("TxGain", DoubleValue (offset + Irss) );
184  devices.Add (wifi.Install (wifiPhy, wifiMac, c.Get (2)));
185 
186  // Note that with FixedRssLossModel, the positions below are not
187  // used for received signal strength.
188  MobilityHelper mobility;
189  Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();
190  positionAlloc->Add (Vector (0.0, 0.0, 0.0));
191  positionAlloc->Add (Vector (distanceToRx, 0.0, 0.0));
192  positionAlloc->Add (Vector (-1*distanceToRx, 0.0, 0.0));
193  mobility.SetPositionAllocator (positionAlloc);
194  mobility.SetMobilityModel ("ns3::ConstantPositionMobilityModel");
195  mobility.Install (c);
196 
197  // InternetStackHelper internet;
198  internet.Install (c);
199 
200  Ipv4AddressHelper ipv4;
201  NS_LOG_INFO ("Assign IP Addresses.");
202  ipv4.SetBase ("10.1.1.0", "255.255.255.0");
203  Ipv4InterfaceContainer i = ipv4.Assign (devices);
204 
205  TypeId tid = TypeId::LookupByName ("ns3::UdpSocketFactory");
206  Ptr<Socket> recvSink = Socket::CreateSocket (c.Get (0), tid);
207  InetSocketAddress local = InetSocketAddress (Ipv4Address ("10.1.1.1"), 80);
208  recvSink->Bind (local);
209  recvSink->SetRecvCallback (MakeCallback (&WifiInterferenceTestCase::ReceivePacket, this));
210 
211  Ptr<Socket> source = Socket::CreateSocket (c.Get (1), tid);
212  InetSocketAddress remote = InetSocketAddress (Ipv4Address ("255.255.255.255"), 80);
213  source->Connect (remote);
214 
215  // Interferer will send to a different port; we will not see a
216  // "Received packet" message
217  Ptr<Socket> interferer = Socket::CreateSocket (c.Get (2), tid);
218  InetSocketAddress interferingAddr = InetSocketAddress (Ipv4Address ("255.255.255.255"), 49000);
219  interferer->Connect (interferingAddr);
220 
221  Config::Connect ("/NodeList/0/DeviceList/0/$ns3::WifiNetDevice/Phy/$ns3::YansWifiPhy/EndSync", MakeCallback (&WifiInterferenceTestCase::PrintEndSync, this));
222  // Tracing
223 // wifiPhy.EnablePcap ("wifi-simple-interference", devices.Get (0));
224 
225  Simulator::ScheduleWithContext (source->GetNode ()->GetId (),
226  Seconds (startTime), &GenerateTraffic,
227  source, PpacketSize, numPackets, interPacketInterval);
228 
229  Simulator::ScheduleWithContext (interferer->GetNode ()->GetId (),
230  Seconds (startTime + delta/1000000.0), &GenerateTraffic,
231  interferer, IpacketSize, numPackets, interPacketInterval);
232 
233  Simulator::Run ();
234  Simulator::Destroy ();
235 
236  return m_PER;
237 }
238 
239 void
240 WifiInterferenceTestCase::DoRun (void)
241 {
242 
243  std::string phyMode ("DsssRate1Mbps");
244  double Prss = -90; // -dBm
245  double Irss = -90; // -dBm
246  double delta = 0; // microseconds
247  uint32_t PpacketSize = 1000; // bytes
248  uint32_t IpacketSize = 1000; // bytes
249  bool verbose = false;
250  double PER, PER1, PER2;
251  InternetStackHelper internet;
252 
253  // Compute the packet error rate (PER) when delta=0 microseconds. This
254  // means that the interferer arrives at exactly the same time as the
255  // intended packet
256  PER = WifiSimpleInterference (phyMode,Prss,Irss,delta,PpacketSize,IpacketSize,verbose,internet);
257 
258  // Now rerun this test case and compute the PER when the delta time between
259  // arrival of the intended frame and interferer is 1 microsecond.
260  delta = 1;
261  PER1 = WifiSimpleInterference (phyMode,Prss,Irss,delta,PpacketSize,IpacketSize,verbose,internet);
262 
263  // Now rerun this test case and compute the PER when the delta time between
264  // arrival of the intended frame and interferer is 2 microseconds.
265  delta = 2;
266  PER2 = WifiSimpleInterference (phyMode,Prss,Irss,delta,PpacketSize,IpacketSize,verbose,internet);
267 
268  double PERDiff1 = PER - PER1;
269 
270  double PERDiff2 = PER1 - PER2;
271 
272  NS_TEST_ASSERT_MSG_EQ (PERDiff1, PERDiff2,
273  "The PER difference due to 1 microsecond difference in arrival shouldn't depend on absolute arrival");
274 }
275 
276 class WifiInterferenceTestSuite : public TestSuite
277 {
278 public:
279  WifiInterferenceTestSuite ();
280 };
281 
282 WifiInterferenceTestSuite::WifiInterferenceTestSuite ()
283  : TestSuite ("ns3-wifi-interference", UNIT)
284 {
285  AddTestCase (new WifiInterferenceTestCase, TestCase::QUICK);
286 }
287 
288 static WifiInterferenceTestSuite wifiInterferenceTestSuite;
289