A Discrete-Event Network Simulator
API
interference-helper.cc
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2005,2006 INRIA
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  * Authors: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
19  * Sébastien Deronne <sebastien.deronne@gmail.com>
20  */
21 
22 #include "interference-helper.h"
23 #include "wifi-phy.h"
24 #include "error-rate-model.h"
25 #include "ns3/simulator.h"
26 #include "ns3/log.h"
27 #include <algorithm>
28 
29 namespace ns3 {
30 
31 NS_LOG_COMPONENT_DEFINE ("InterferenceHelper");
32 
33 /****************************************************************
34  * Phy event class
35  ****************************************************************/
36 
37 InterferenceHelper::Event::Event (uint32_t size, WifiTxVector txVector,
38  enum WifiPreamble preamble,
39  Time duration, double rxPower)
40  : m_size (size),
41  m_txVector (txVector),
42  m_preamble (preamble),
43  m_startTime (Simulator::Now ()),
44  m_endTime (m_startTime + duration),
45  m_rxPowerW (rxPower)
46 {
47 }
48 
49 InterferenceHelper::Event::~Event ()
50 {
51 }
52 
53 Time
54 InterferenceHelper::Event::GetDuration (void) const
55 {
56  return m_endTime - m_startTime;
57 }
58 
59 Time
60 InterferenceHelper::Event::GetStartTime (void) const
61 {
62  return m_startTime;
63 }
64 
65 Time
66 InterferenceHelper::Event::GetEndTime (void) const
67 {
68  return m_endTime;
69 }
70 
71 double
72 InterferenceHelper::Event::GetRxPowerW (void) const
73 {
74  return m_rxPowerW;
75 }
76 
77 uint32_t
78 InterferenceHelper::Event::GetSize (void) const
79 {
80  return m_size;
81 }
82 
83 WifiTxVector
84 InterferenceHelper::Event::GetTxVector (void) const
85 {
86  return m_txVector;
87 }
88 
89 WifiMode
90 InterferenceHelper::Event::GetPayloadMode (void) const
91 {
92  return m_txVector.GetMode ();
93 }
94 
95 enum WifiPreamble
96 InterferenceHelper::Event::GetPreambleType (void) const
97 {
98  return m_preamble;
99 }
100 
101 
102 /****************************************************************
103  * Class which records SNIR change events for a
104  * short period of time.
105  ****************************************************************/
106 
107 InterferenceHelper::NiChange::NiChange (Time time, double delta)
108  : m_time (time),
109  m_delta (delta)
110 {
111 }
112 
113 Time
114 InterferenceHelper::NiChange::GetTime (void) const
115 {
116  return m_time;
117 }
118 
119 double
120 InterferenceHelper::NiChange::GetDelta (void) const
121 {
122  return m_delta;
123 }
124 
125 bool
126 InterferenceHelper::NiChange::operator < (const InterferenceHelper::NiChange& o) const
127 {
128  return (m_time < o.m_time);
129 }
130 
131 
132 /****************************************************************
133  * The actual InterferenceHelper
134  ****************************************************************/
135 
136 InterferenceHelper::InterferenceHelper ()
137  : m_errorRateModel (0),
138  m_firstPower (0.0),
139  m_rxing (false)
140 {
141 }
142 
143 InterferenceHelper::~InterferenceHelper ()
144 {
145  EraseEvents ();
146  m_errorRateModel = 0;
147 }
148 
149 Ptr<InterferenceHelper::Event>
150 InterferenceHelper::Add (uint32_t size, WifiTxVector txVector,
151  enum WifiPreamble preamble,
152  Time duration, double rxPowerW)
153 {
154  Ptr<InterferenceHelper::Event> event;
155 
156  event = Create<InterferenceHelper::Event> (size,
157  txVector,
158  preamble,
159  duration,
160  rxPowerW);
161  AppendEvent (event);
162  return event;
163 }
164 
165 
166 void
167 InterferenceHelper::SetNoiseFigure (double value)
168 {
169  m_noiseFigure = value;
170 }
171 
172 double
173 InterferenceHelper::GetNoiseFigure (void) const
174 {
175  return m_noiseFigure;
176 }
177 
178 void
179 InterferenceHelper::SetErrorRateModel (Ptr<ErrorRateModel> rate)
180 {
181  m_errorRateModel = rate;
182 }
183 
184 Ptr<ErrorRateModel>
185 InterferenceHelper::GetErrorRateModel (void) const
186 {
187  return m_errorRateModel;
188 }
189 
190 Time
191 InterferenceHelper::GetEnergyDuration (double energyW)
192 {
193  Time now = Simulator::Now ();
194  double noiseInterferenceW = 0.0;
195  Time end = now;
196  noiseInterferenceW = m_firstPower;
197  for (NiChanges::const_iterator i = m_niChanges.begin (); i != m_niChanges.end (); i++)
198  {
199  noiseInterferenceW += i->GetDelta ();
200  end = i->GetTime ();
201  if (end < now)
202  {
203  continue;
204  }
205  if (noiseInterferenceW < energyW)
206  {
207  break;
208  }
209  }
210  return end > now ? end - now : MicroSeconds (0);
211 }
212 
213 void
214 InterferenceHelper::AppendEvent (Ptr<InterferenceHelper::Event> event)
215 {
216  Time now = Simulator::Now ();
217  if (!m_rxing)
218  {
219  NiChanges::iterator nowIterator = GetPosition (now);
220  for (NiChanges::iterator i = m_niChanges.begin (); i != nowIterator; i++)
221  {
222  m_firstPower += i->GetDelta ();
223  }
224  m_niChanges.erase (m_niChanges.begin (), nowIterator);
225  m_niChanges.insert (m_niChanges.begin (), NiChange (event->GetStartTime (), event->GetRxPowerW ()));
226  }
227  else
228  {
229  AddNiChangeEvent (NiChange (event->GetStartTime (), event->GetRxPowerW ()));
230  }
231  AddNiChangeEvent (NiChange (event->GetEndTime (), -event->GetRxPowerW ()));
232 
233 }
234 
235 
236 double
237 InterferenceHelper::CalculateSnr (double signal, double noiseInterference, uint32_t channelWidth) const
238 {
239  //thermal noise at 290K in J/s = W
240  static const double BOLTZMANN = 1.3803e-23;
241  //Nt is the power of thermal noise in W
242  double Nt = BOLTZMANN * 290.0 * channelWidth * 1000000;
243  //receiver noise Floor (W) which accounts for thermal noise and non-idealities of the receiver
244  double noiseFloor = m_noiseFigure * Nt;
245  double noise = noiseFloor + noiseInterference;
246  double snr = signal / noise; //linear scale
247  NS_LOG_DEBUG ("bandwidth(MHz)=" << channelWidth << ", signal(W)= " << signal << ", noise(W)=" << noiseFloor << ", interference(W)=" << noiseInterference << ", snr(linear)=" << snr);
248  return snr;
249 }
250 
251 double
252 InterferenceHelper::CalculateNoiseInterferenceW (Ptr<InterferenceHelper::Event> event, NiChanges *ni) const
253 {
254  double noiseInterference = m_firstPower;
255  NS_ASSERT (m_rxing);
256  for (NiChanges::const_iterator i = m_niChanges.begin () + 1; i != m_niChanges.end (); i++)
257  {
258  if ((event->GetEndTime () == i->GetTime ()) && event->GetRxPowerW () == -i->GetDelta ())
259  {
260  break;
261  }
262  ni->push_back (*i);
263  }
264  ni->insert (ni->begin (), NiChange (event->GetStartTime (), noiseInterference));
265  ni->push_back (NiChange (event->GetEndTime (), 0));
266  return noiseInterference;
267 }
268 
269 double
270 InterferenceHelper::CalculateChunkSuccessRate (double snir, Time duration, WifiMode mode, WifiTxVector txVector) const
271 {
272  if (duration == NanoSeconds (0))
273  {
274  return 1.0;
275  }
276  uint32_t rate = mode.GetPhyRate (txVector);
277  uint64_t nbits = (uint64_t)(rate * duration.GetSeconds ());
278  double csr = m_errorRateModel->GetChunkSuccessRate (mode, txVector, snir, (uint32_t)nbits);
279  return csr;
280 }
281 
282 double
283 InterferenceHelper::CalculatePlcpPayloadPer (Ptr<const InterferenceHelper::Event> event, NiChanges *ni) const
284 {
285  NS_LOG_FUNCTION (this);
286  double psr = 1.0; /* Packet Success Rate */
287  NiChanges::iterator j = ni->begin ();
288  Time previous = (*j).GetTime ();
289  WifiMode payloadMode = event->GetPayloadMode ();
290  WifiPreamble preamble = event->GetPreambleType ();
291  Time plcpHeaderStart = (*j).GetTime () + WifiPhy::GetPlcpPreambleDuration (event->GetTxVector (), preamble); //packet start time + preamble
292  Time plcpHsigHeaderStart = plcpHeaderStart + WifiPhy::GetPlcpHeaderDuration (event->GetTxVector (), preamble); //packet start time + preamble + L-SIG
293  Time plcpHtTrainingSymbolsStart = plcpHsigHeaderStart + WifiPhy::GetPlcpHtSigHeaderDuration (preamble) + WifiPhy::GetPlcpVhtSigA1Duration (preamble) + WifiPhy::GetPlcpVhtSigA2Duration (preamble); //packet start time + preamble + L-SIG + HT-SIG or VHT-SIG-A (A1 + A2)
294  Time plcpPayloadStart = plcpHtTrainingSymbolsStart + WifiPhy::GetPlcpHtTrainingSymbolDuration (preamble, event->GetTxVector ()) + WifiPhy::GetPlcpVhtSigBDuration (preamble); //packet start time + preamble + L-SIG + HT-SIG or VHT-SIG-A (A1 + A2) + (V)HT Training + VHT-SIG-B
295  double noiseInterferenceW = (*j).GetDelta ();
296  double powerW = event->GetRxPowerW ();
297  j++;
298  while (ni->end () != j)
299  {
300  Time current = (*j).GetTime ();
301  NS_LOG_DEBUG ("previous= " << previous << ", current=" << current);
302  NS_ASSERT (current >= previous);
303  //Case 1: Both previous and current point to the payload
304  if (previous >= plcpPayloadStart)
305  {
306  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
307  noiseInterferenceW,
308  event->GetTxVector ().GetChannelWidth ()),
309  current - previous,
310  payloadMode, event->GetTxVector ());
311 
312  NS_LOG_DEBUG ("Both previous and current point to the payload: mode=" << payloadMode << ", psr=" << psr);
313  }
314  //Case 2: previous is before payload and current is in the payload
315  else if (current >= plcpPayloadStart)
316  {
317  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
318  noiseInterferenceW,
319  event->GetTxVector ().GetChannelWidth ()),
320  current - plcpPayloadStart,
321  payloadMode, event->GetTxVector ());
322  NS_LOG_DEBUG ("previous is before payload and current is in the payload: mode=" << payloadMode << ", psr=" << psr);
323  }
324 
325  noiseInterferenceW += (*j).GetDelta ();
326  previous = (*j).GetTime ();
327  j++;
328  }
329 
330  double per = 1 - psr;
331  return per;
332 }
333 
334 double
335 InterferenceHelper::CalculatePlcpHeaderPer (Ptr<const InterferenceHelper::Event> event, NiChanges *ni) const
336 {
337  NS_LOG_FUNCTION (this);
338  double psr = 1.0; /* Packet Success Rate */
339  NiChanges::iterator j = ni->begin ();
340  Time previous = (*j).GetTime ();
341  WifiMode payloadMode = event->GetPayloadMode ();
342  WifiPreamble preamble = event->GetPreambleType ();
343  WifiMode htHeaderMode;
344  if (preamble == WIFI_PREAMBLE_HT_MF)
345  {
346  //mode for PLCP header fields sent with HT modulation
347  htHeaderMode = WifiPhy::GetHtPlcpHeaderMode (payloadMode);
348  }
349  else if (preamble == WIFI_PREAMBLE_VHT)
350  {
351  //mode for PLCP header fields sent with VHT modulation
352  htHeaderMode = WifiPhy::GetVhtPlcpHeaderMode (payloadMode);
353  }
354  WifiMode headerMode = WifiPhy::GetPlcpHeaderMode (payloadMode, preamble, event->GetTxVector ());
355  Time plcpHeaderStart = (*j).GetTime () + WifiPhy::GetPlcpPreambleDuration (event->GetTxVector (), preamble); //packet start time + preamble
356  Time plcpHsigHeaderStart = plcpHeaderStart + WifiPhy::GetPlcpHeaderDuration (event->GetTxVector (), preamble); //packet start time + preamble + L-SIG
357  Time plcpHtTrainingSymbolsStart = plcpHsigHeaderStart + WifiPhy::GetPlcpHtSigHeaderDuration (preamble) + WifiPhy::GetPlcpVhtSigA1Duration (preamble) + WifiPhy::GetPlcpVhtSigA2Duration (preamble); //packet start time + preamble + L-SIG + HT-SIG or VHT-SIG-A (A1 + A2)
358  Time plcpPayloadStart = plcpHtTrainingSymbolsStart + WifiPhy::GetPlcpHtTrainingSymbolDuration (preamble, event->GetTxVector ()) + WifiPhy::GetPlcpVhtSigBDuration (preamble); //packet start time + preamble + L-SIG + HT-SIG or VHT-SIG-A (A1 + A2) + (V)HT Training + VHT-SIG-B
359  double noiseInterferenceW = (*j).GetDelta ();
360  double powerW = event->GetRxPowerW ();
361  j++;
362  while (ni->end () != j)
363  {
364  Time current = (*j).GetTime ();
365  NS_LOG_DEBUG ("previous= " << previous << ", current=" << current);
366  NS_ASSERT (current >= previous);
367  //Case 1: previous and current after playload start: nothing to do
368  if (previous >= plcpPayloadStart)
369  {
370  psr *= 1;
371  NS_LOG_DEBUG ("Case 1 - previous and current after playload start: nothing to do");
372  }
373  //Case 2: previous is in (V)HT training or in VHT-SIG-B: Non (V)HT will not enter here since it didn't enter in the last two and they are all the same for non (V)HT
374  else if (previous >= plcpHtTrainingSymbolsStart)
375  {
376  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
377  //Case 2a: current after payload start
378  if (current >= plcpPayloadStart)
379  {
380  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
381  noiseInterferenceW,
382  event->GetTxVector ().GetChannelWidth ()),
383  plcpPayloadStart - previous,
384  htHeaderMode, event->GetTxVector ());
385 
386  NS_LOG_DEBUG ("Case 2a - previous is in (V)HT training or in VHT-SIG-B and current after payload start: mode=" << htHeaderMode << ", psr=" << psr);
387  }
388  //Case 2b: current is in (V)HT training or in VHT-SIG-B
389  else
390  {
391  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
392  noiseInterferenceW,
393  event->GetTxVector ().GetChannelWidth ()),
394  current - previous,
395  htHeaderMode, event->GetTxVector ());
396 
397  NS_LOG_DEBUG ("Case 2b - previous is in (V)HT training or in VHT-SIG-B and current is in (V)HT training or in VHT-SIG-B: mode=" << htHeaderMode << ", psr=" << psr);
398  }
399  }
400  //Case 3: previous is in HT-SIG or VHT-SIG-A: Non (V)HT will not enter here since it didn't enter in the last two and they are all the same for non (V)HT
401  else if (previous >= plcpHsigHeaderStart)
402  {
403  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
404  //Case 3a: current after payload start
405  if (current >= plcpPayloadStart)
406  {
407  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
408  noiseInterferenceW,
409  event->GetTxVector ().GetChannelWidth ()),
410  plcpPayloadStart - plcpHtTrainingSymbolsStart,
411  htHeaderMode, event->GetTxVector ());
412 
413  //Case 3ai: VHT format
414  if (preamble == WIFI_PREAMBLE_VHT)
415  {
416  //VHT-SIG-A is sent using legacy OFDM modulation
417  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
418  noiseInterferenceW,
419  event->GetTxVector ().GetChannelWidth ()),
420  plcpHtTrainingSymbolsStart - previous,
421  headerMode, event->GetTxVector ());
422 
423  NS_LOG_DEBUG ("Case 3ai - previous is in VHT-SIG-A and current after payload start: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
424  }
425  //Case 3aii: HT mixed format of HT greenfield
426  else
427  {
428  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
429  noiseInterferenceW,
430  event->GetTxVector ().GetChannelWidth ()),
431  plcpHtTrainingSymbolsStart - previous,
432  htHeaderMode, event->GetTxVector ());
433 
434  NS_LOG_DEBUG ("Case 3aii - previous is in HT-SIG and current after payload start: mode=" << htHeaderMode << ", psr=" << psr);
435  }
436  }
437  //Case 3b: current is in (V)HT training or in VHT-SIG-B
438  else if (current >= plcpHtTrainingSymbolsStart)
439  {
440  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
441  noiseInterferenceW,
442  event->GetTxVector ().GetChannelWidth ()),
443  current - plcpHtTrainingSymbolsStart,
444  htHeaderMode, event->GetTxVector ());
445 
446  //Case 3bi: VHT format
447  if (preamble == WIFI_PREAMBLE_VHT)
448  {
449  //VHT-SIG-A is sent using legacy OFDM modulation
450  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
451  noiseInterferenceW,
452  event->GetTxVector ().GetChannelWidth ()),
453  plcpHtTrainingSymbolsStart - previous,
454  headerMode, event->GetTxVector ());
455 
456  NS_LOG_DEBUG ("Case 3bi - previous is in VHT-SIG-A and current is in VHT training or in VHT-SIG-B: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
457  }
458  //Case 3bii: HT mixed format of HT greenfield
459  else
460  {
461  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
462  noiseInterferenceW,
463  event->GetTxVector ().GetChannelWidth ()),
464  plcpHtTrainingSymbolsStart - previous,
465  htHeaderMode, event->GetTxVector ());
466 
467  NS_LOG_DEBUG ("Case 3bii - previous is in HT-SIG and current is in HT training: mode=" << htHeaderMode << ", psr=" << psr);
468  }
469  }
470  //Case 3c: current with previous in HT-SIG or VHT-SIG-A
471  else
472  {
473  //Case 3bi: VHT format
474  if (preamble == WIFI_PREAMBLE_VHT)
475  {
476  //VHT-SIG-A is sent using legacy OFDM modulation
477  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
478  noiseInterferenceW,
479  event->GetTxVector ().GetChannelWidth ()),
480  current - previous,
481  headerMode, event->GetTxVector ());
482 
483  NS_LOG_DEBUG ("Case 3ci - previous with current in VHT-SIG-A: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
484  }
485  //Case 3bii: HT mixed format of HT greenfield
486  else
487  {
488  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
489  noiseInterferenceW,
490  event->GetTxVector ().GetChannelWidth ()),
491  current - previous,
492  htHeaderMode, event->GetTxVector ());
493 
494  NS_LOG_DEBUG ("Case 3cii - previous with current in HT-SIG: mode=" << htHeaderMode << ", psr=" << psr);
495  }
496  }
497  }
498  //Case 4: previous in L-SIG: HT GF will not reach here because it will execute the previous if and exit
499  else if (previous >= plcpHeaderStart)
500  {
501  NS_ASSERT (preamble != WIFI_PREAMBLE_HT_GF);
502  //Case 4a: current after payload start
503  if (current >= plcpPayloadStart)
504  {
505  //Case 4ai: Non (V)HT format
506  if (preamble == WIFI_PREAMBLE_LONG || preamble == WIFI_PREAMBLE_SHORT)
507  {
508  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
509  noiseInterferenceW,
510  event->GetTxVector ().GetChannelWidth ()),
511  plcpPayloadStart - previous,
512  headerMode, event->GetTxVector ());
513 
514  NS_LOG_DEBUG ("Case 4ai - previous in L-SIG and current after payload start: mode=" << headerMode << ", psr=" << psr);
515  }
516  //Case 4aii: VHT format
517  else if (preamble == WIFI_PREAMBLE_VHT)
518  {
519  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
520  noiseInterferenceW,
521  event->GetTxVector ().GetChannelWidth ()),
522  plcpPayloadStart - plcpHtTrainingSymbolsStart,
523  htHeaderMode, event->GetTxVector ());
524 
525  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
526  noiseInterferenceW,
527  event->GetTxVector ().GetChannelWidth ()),
528  plcpHtTrainingSymbolsStart - previous,
529  headerMode, event->GetTxVector ());
530 
531  NS_LOG_DEBUG ("Case 4aii - previous is in L-SIG and current after payload start: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
532  }
533  //Case 4aiii: HT mixed format
534  else
535  {
536  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
537  noiseInterferenceW,
538  event->GetTxVector ().GetChannelWidth ()),
539  plcpPayloadStart - plcpHsigHeaderStart,
540  htHeaderMode, event->GetTxVector ());
541 
542  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
543  noiseInterferenceW,
544  event->GetTxVector ().GetChannelWidth ()),
545  plcpHsigHeaderStart - previous,
546  headerMode, event->GetTxVector ());
547 
548  NS_LOG_DEBUG ("Case 4aiii - previous in L-SIG and current after payload start: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
549  }
550  }
551  //Case 4b: current is in (V)HT training or in VHT-SIG-B. Non (V)HT will not come here since it went in previous if or if the previous if is not true this will be not true
552  else if (current >= plcpHtTrainingSymbolsStart)
553  {
554  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
555 
556  //Case 4bi: VHT format
557  if (preamble == WIFI_PREAMBLE_VHT)
558  {
559  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
560  noiseInterferenceW,
561  event->GetTxVector ().GetChannelWidth ()),
562  current - plcpHtTrainingSymbolsStart,
563  htHeaderMode, event->GetTxVector ());
564 
565  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
566  noiseInterferenceW,
567  event->GetTxVector ().GetChannelWidth ()),
568  plcpHtTrainingSymbolsStart - previous,
569  headerMode, event->GetTxVector ());
570 
571  NS_LOG_DEBUG ("Case 4bi - previous is in L-SIG and current in VHT training or in VHT-SIG-B: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
572  }
573  //Case 4bii: HT mixed format
574  else
575  {
576  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
577  noiseInterferenceW,
578  event->GetTxVector ().GetChannelWidth ()),
579  current - plcpHsigHeaderStart,
580  htHeaderMode, event->GetTxVector ());
581 
582  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
583  noiseInterferenceW,
584  event->GetTxVector ().GetChannelWidth ()),
585  plcpHsigHeaderStart - previous,
586  headerMode, event->GetTxVector ());
587 
588  NS_LOG_DEBUG ("Case 4bii - previous in L-SIG and current in HT training: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
589  }
590  }
591  //Case 4c: current in HT-SIG or in VHT-SIG-A. Non (V)HT will not come here since it went in previous if or if the previous if is not true this will be not true
592  else if (current >= plcpHsigHeaderStart)
593  {
594  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
595 
596  //Case 4ci: VHT format
597  if (preamble == WIFI_PREAMBLE_VHT)
598  {
599  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
600  noiseInterferenceW,
601  event->GetTxVector ().GetChannelWidth ()),
602  current - previous,
603  headerMode, event->GetTxVector ());
604 
605  NS_LOG_DEBUG ("Case 4ci - previous is in L-SIG and current in VHT-SIG-A: mode=" << headerMode << ", psr=" << psr);
606  }
607  //Case 4cii: HT mixed format
608  else
609  {
610  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
611  noiseInterferenceW,
612  event->GetTxVector ().GetChannelWidth ()),
613  current - plcpHsigHeaderStart,
614  htHeaderMode, event->GetTxVector ());
615 
616  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
617  noiseInterferenceW,
618  event->GetTxVector ().GetChannelWidth ()),
619  plcpHsigHeaderStart - previous,
620  headerMode, event->GetTxVector ());
621 
622  NS_LOG_DEBUG ("Case 4cii - previous in L-SIG and current in HT-SIG: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
623  }
624  }
625  //Case 4d: current with previous in L-SIG
626  else
627  {
628  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
629  noiseInterferenceW,
630  event->GetTxVector ().GetChannelWidth ()),
631  current - previous,
632  headerMode, event->GetTxVector ());
633 
634  NS_LOG_DEBUG ("Case 3c - current with previous in L-SIG: mode=" << headerMode << ", psr=" << psr);
635  }
636  }
637  //Case 5: previous is in the preamble works for all cases
638  else
639  {
640  //Case 5a: current after payload start
641  if (current >= plcpPayloadStart)
642  {
643  //Case 5ai: Non HT format (No HT-SIG or Training Symbols)
644  if (preamble == WIFI_PREAMBLE_LONG || preamble == WIFI_PREAMBLE_SHORT)
645  {
646  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
647  noiseInterferenceW,
648  event->GetTxVector ().GetChannelWidth ()),
649  plcpPayloadStart - plcpHeaderStart,
650  headerMode, event->GetTxVector ());
651 
652  NS_LOG_DEBUG ("Case 5a - previous is in the preamble and current is after payload start: mode=" << headerMode << ", psr=" << psr);
653  }
654  //Case 5aii: VHT format
655  else if (preamble == WIFI_PREAMBLE_VHT)
656  {
657  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
658  noiseInterferenceW,
659  event->GetTxVector ().GetChannelWidth ()),
660  plcpPayloadStart - plcpHtTrainingSymbolsStart,
661  htHeaderMode, event->GetTxVector ());
662 
663  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
664  noiseInterferenceW,
665  event->GetTxVector ().GetChannelWidth ()),
666  plcpHtTrainingSymbolsStart - plcpHeaderStart,
667  headerMode, event->GetTxVector ());
668 
669  NS_LOG_DEBUG ("Case 5aii - previous is in the preamble and current is after payload start: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
670  }
671 
672  //Case 5aiii: HT format
673  else
674  {
675  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
676  noiseInterferenceW,
677  event->GetTxVector ().GetChannelWidth ()),
678  plcpPayloadStart - plcpHsigHeaderStart,
679  htHeaderMode, event->GetTxVector ());
680 
681  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
682  noiseInterferenceW,
683  event->GetTxVector ().GetChannelWidth ()),
684  plcpHsigHeaderStart - plcpHeaderStart, //HT GF: plcpHsigHeaderStart - plcpHeaderStart = 0
685  headerMode, event->GetTxVector ());
686 
687  NS_LOG_DEBUG ("Case 4a - previous is in the preamble and current is after payload start: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
688  }
689  }
690  //Case 5b: current is in (V)HT training or in VHT-SIG-B. Non (V)HT will not come here since it went in previous if or if the previous if is not true this will be not true
691  else if (current >= plcpHtTrainingSymbolsStart)
692  {
693  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
694 
695  //Case 5bi: VHT format
696  if (preamble == WIFI_PREAMBLE_VHT)
697  {
698  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
699  noiseInterferenceW,
700  event->GetTxVector ().GetChannelWidth ()),
701  current - plcpHtTrainingSymbolsStart,
702  htHeaderMode, event->GetTxVector ());
703 
704  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
705  noiseInterferenceW,
706  event->GetTxVector ().GetChannelWidth ()),
707  plcpHtTrainingSymbolsStart - plcpHeaderStart,
708  headerMode, event->GetTxVector ());
709 
710  NS_LOG_DEBUG ("Case 5bi - previous is in the preamble and current in VHT training or in VHT-SIG-B: VHT mode=" << htHeaderMode << ", non-VHT mode=" << headerMode << ", psr=" << psr);
711  }
712  //Case 45ii: HT mixed format
713  else
714  {
715  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
716  noiseInterferenceW,
717  event->GetTxVector ().GetChannelWidth ()),
718  current - plcpHsigHeaderStart,
719  htHeaderMode, event->GetTxVector ());
720 
721  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
722  noiseInterferenceW,
723  event->GetTxVector ().GetChannelWidth ()),
724  plcpHsigHeaderStart - plcpHeaderStart,
725  headerMode, event->GetTxVector ());
726 
727  NS_LOG_DEBUG ("Case 5bii - previous is in the preamble and current in HT training: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
728  }
729  }
730  //Case 5c: current in HT-SIG or in VHT-SIG-A. Non (V)HT will not come here since it went in previous if or if the previous if is not true this will be not true
731  else if (current >= plcpHsigHeaderStart)
732  {
733  NS_ASSERT ((preamble != WIFI_PREAMBLE_LONG) && (preamble != WIFI_PREAMBLE_SHORT));
734 
735  //Case 5ci: VHT format
736  if (preamble == WIFI_PREAMBLE_VHT)
737  {
738  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
739  noiseInterferenceW,
740  event->GetTxVector ().GetChannelWidth ()),
741  current - plcpHeaderStart,
742  headerMode, event->GetTxVector ());
743 
744  NS_LOG_DEBUG ("Case 5ci - previous is in preamble and current in VHT-SIG-A: mode=" << headerMode << ", psr=" << psr);
745  }
746  //Case 5cii: HT mixed format
747  else
748  {
749  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
750  noiseInterferenceW,
751  event->GetTxVector ().GetChannelWidth ()),
752  current - plcpHsigHeaderStart,
753  htHeaderMode, event->GetTxVector ());
754 
755  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
756  noiseInterferenceW,
757  event->GetTxVector ().GetChannelWidth ()),
758  plcpHsigHeaderStart - plcpHeaderStart, //HT GF: plcpHsigHeaderStart - plcpHeaderStart = 0
759  headerMode, event->GetTxVector ());
760 
761  NS_LOG_DEBUG ("Case 5cii - previous in preamble and current in HT-SIG: HT mode=" << htHeaderMode << ", non-HT mode=" << headerMode << ", psr=" << psr);
762  }
763  }
764  //Case 5d: current is in L-SIG. HT GF will not come here
765  else if (current >= plcpHeaderStart)
766  {
767  NS_ASSERT (preamble != WIFI_PREAMBLE_HT_GF);
768 
769  psr *= CalculateChunkSuccessRate (CalculateSnr (powerW,
770  noiseInterferenceW,
771  event->GetTxVector ().GetChannelWidth ()),
772  current - plcpHeaderStart,
773  headerMode, event->GetTxVector ());
774 
775  NS_LOG_DEBUG ("Case 5d - previous is in the preamble and current is in L-SIG: mode=" << headerMode << ", psr=" << psr);
776  }
777  }
778 
779  noiseInterferenceW += (*j).GetDelta ();
780  previous = (*j).GetTime ();
781  j++;
782  }
783 
784  double per = 1 - psr;
785  return per;
786 }
787 
788 struct InterferenceHelper::SnrPer
789 InterferenceHelper::CalculatePlcpPayloadSnrPer (Ptr<InterferenceHelper::Event> event)
790 {
791  NiChanges ni;
792  double noiseInterferenceW = CalculateNoiseInterferenceW (event, &ni);
793  double snr = CalculateSnr (event->GetRxPowerW (),
794  noiseInterferenceW,
795  event->GetTxVector ().GetChannelWidth ());
796 
797  /* calculate the SNIR at the start of the packet and accumulate
798  * all SNIR changes in the snir vector.
799  */
800  double per = CalculatePlcpPayloadPer (event, &ni);
801 
802  struct SnrPer snrPer;
803  snrPer.snr = snr;
804  snrPer.per = per;
805  return snrPer;
806 }
807 
808 struct InterferenceHelper::SnrPer
809 InterferenceHelper::CalculatePlcpHeaderSnrPer (Ptr<InterferenceHelper::Event> event)
810 {
811  NiChanges ni;
812  double noiseInterferenceW = CalculateNoiseInterferenceW (event, &ni);
813  double snr = CalculateSnr (event->GetRxPowerW (),
814  noiseInterferenceW,
815  event->GetTxVector ().GetChannelWidth ());
816 
817  /* calculate the SNIR at the start of the plcp header and accumulate
818  * all SNIR changes in the snir vector.
819  */
820  double per = CalculatePlcpHeaderPer (event, &ni);
821 
822  struct SnrPer snrPer;
823  snrPer.snr = snr;
824  snrPer.per = per;
825  return snrPer;
826 }
827 
828 void
829 InterferenceHelper::EraseEvents (void)
830 {
831  m_niChanges.clear ();
832  m_rxing = false;
833  m_firstPower = 0.0;
834 }
835 
836 InterferenceHelper::NiChanges::iterator
837 InterferenceHelper::GetPosition (Time moment)
838 {
839  return std::upper_bound (m_niChanges.begin (), m_niChanges.end (), NiChange (moment, 0));
840 }
841 
842 void
843 InterferenceHelper::AddNiChangeEvent (NiChange change)
844 {
845  m_niChanges.insert (GetPosition (change.GetTime ()), change);
846 }
847 
848 void
849 InterferenceHelper::NotifyRxStart ()
850 {
851  NS_LOG_FUNCTION (this);
852  m_rxing = true;
853 }
854 
855 void
856 InterferenceHelper::NotifyRxEnd ()
857 {
858  NS_LOG_FUNCTION (this);
859  m_rxing = false;
860 }
861 
862 } //namespace ns3
ns3::Time
Simulation virtual time values and global simulation resolution.
Definition: nstime.h:102
ns3::InterferenceHelper::SnrPer
A struct for both SNR and PER.
Definition: interference-helper.h:127
ns3::Ptr
Smart pointer class similar to boost::intrusive_ptr.
Definition: ptr.h:73
NS_LOG_FUNCTION
#define NS_LOG_FUNCTION(parameters)
If log level LOG_FUNCTION is enabled, this macro will output all input parameters separated by "...
Definition: log-macros-enabled.h:213
ns3::Simulator
Control the scheduling of simulation events.
Definition: simulator.h:70
ns3::InterferenceHelper::GetErrorRateModel
Ptr< ErrorRateModel > GetErrorRateModel(void) const
Return the error rate model.
Definition: interference-helper.cc:185
ns3::WifiTxVector
This class mimics the TXVECTOR which is to be passed to the PHY in order to define the parameters whi...
Definition: wifi-tx-vector.h:61
ns3::InterferenceHelper::NiChange::operator<
bool operator<(const NiChange &o) const
Compare the event time of two NiChange objects (a < o).
Definition: interference-helper.cc:126
ns3::InterferenceHelper::NiChanges
std::vector< NiChange > NiChanges
typedef for a vector of NiChanges
Definition: interference-helper.h:261
ns3::InterferenceHelper
handles interference calculations
Definition: interference-helper.h:42
ns3::WifiPhy::GetHtPlcpHeaderMode
static WifiMode GetHtPlcpHeaderMode(WifiMode payloadMode)
Definition: wifi-phy.cc:122
ns3::WifiPhy::GetPlcpHtSigHeaderDuration
static Time GetPlcpHtSigHeaderDuration(WifiPreamble preamble)
Definition: wifi-phy.cc:180
NS_ASSERT
#define NS_ASSERT(condition)
At runtime, in debugging builds, if this condition is not true, the program prints the source file...
Definition: assert.h:67
ns3::InterferenceHelper::GetEnergyDuration
Time GetEnergyDuration(double energyW)
Definition: interference-helper.cc:191
NS_LOG_COMPONENT_DEFINE
#define NS_LOG_COMPONENT_DEFINE(name)
Define a Log component with a specific name.
Definition: log.h:201
ns3::InterferenceHelper::CalculateChunkSuccessRate
double CalculateChunkSuccessRate(double snir, Time duration, WifiMode mode, WifiTxVector txVector) const
Calculate the success rate of the chunk given the SINR, duration, and Wi-Fi mode. ...
Definition: interference-helper.cc:270
ns3::InterferenceHelper::Event::GetRxPowerW
double GetRxPowerW(void) const
Return the receive power (w).
Definition: interference-helper.cc:72
ns3::InterferenceHelper::m_errorRateModel
Ptr< ErrorRateModel > m_errorRateModel
Definition: interference-helper.h:327
ns3::InterferenceHelper::GetPosition
NiChanges::iterator GetPosition(Time moment)
Returns an iterator to the first nichange, which is later than moment.
Definition: interference-helper.cc:837
ns3::WifiMode
represent a single transmission modeA WifiMode is implemented by a single integer which is used to lo...
Definition: wifi-mode.h:99
ns3::InterferenceHelper::Event::GetSize
uint32_t GetSize(void) const
Return the size of the packet (bytes).
Definition: interference-helper.cc:78
ns3::WifiPhy::GetVhtPlcpHeaderMode
static WifiMode GetVhtPlcpHeaderMode(WifiMode payloadMode)
Definition: wifi-phy.cc:128
ns3::WifiMode::GetPhyRate
uint64_t GetPhyRate(uint32_t channelWidth, bool isShortGuardInterval, uint8_t nss) const
Definition: wifi-mode.cc:74
ns3::WifiPreamble
WifiPreamble
The type of preamble to be used by an IEEE 802.11 transmission.
Definition: wifi-preamble.h:30
ns3::InterferenceHelper::SetErrorRateModel
void SetErrorRateModel(Ptr< ErrorRateModel > rate)
Set the error rate model for this interference helper.
Definition: interference-helper.cc:179
ns3::Time::GetSeconds
double GetSeconds(void) const
Get an approximation of the time stored in this instance in the indicated unit.
Definition: nstime.h:341
ns3::InterferenceHelper::CalculateNoiseInterferenceW
double CalculateNoiseInterferenceW(Ptr< Event > event, NiChanges *ni) const
Calculate noise and interference power in W.
Definition: interference-helper.cc:252
ns3::InterferenceHelper::Event::GetStartTime
Time GetStartTime(void) const
Return the start time of the signal.
Definition: interference-helper.cc:60
ns3::InterferenceHelper::Event::GetTxVector
WifiTxVector GetTxVector(void) const
Return the TXVECTOR of the packet.
Definition: interference-helper.cc:84
ns3::NanoSeconds
Time NanoSeconds(uint64_t value)
Construct a Time in the indicated unit.
Definition: nstime.h:919
ns3::WifiPhy::GetPlcpHeaderMode
static WifiMode GetPlcpHeaderMode(WifiMode payloadMode, WifiPreamble preamble, WifiTxVector txVector)
Definition: wifi-phy.cc:237
ns3::InterferenceHelper::m_niChanges
NiChanges m_niChanges
Experimental: needed for energy duration calculation.
Definition: interference-helper.h:329
ns3::InterferenceHelper::AddNiChangeEvent
void AddNiChangeEvent(NiChange change)
Add NiChange to the list at the appropriate position.
Definition: interference-helper.cc:843
ns3::InterferenceHelper::NiChange::GetTime
Time GetTime(void) const
Return the event time.
Definition: interference-helper.cc:114
ns3::InterferenceHelper::CalculatePlcpPayloadPer
double CalculatePlcpPayloadPer(Ptr< const Event > event, NiChanges *ni) const
Calculate the error rate of the given plcp payload.
Definition: interference-helper.cc:283
ns3::WIFI_PREAMBLE_VHT
Definition: wifi-preamble.h:36
ns3::InterferenceHelper::m_noiseFigure
double m_noiseFigure
noise figure (linear)
Definition: interference-helper.h:326
ns3
Every class exported by the ns3 library is enclosed in the ns3 namespace.
ns3::InterferenceHelper::NotifyRxStart
void NotifyRxStart()
Notify that RX has started.
Definition: interference-helper.cc:849
ns3::InterferenceHelper::NiChange
Noise and Interference (thus Ni) event.
Definition: interference-helper.h:223
ns3::InterferenceHelper::EraseEvents
void EraseEvents(void)
Erase all events.
Definition: interference-helper.cc:829
ns3::InterferenceHelper::Add
Ptr< InterferenceHelper::Event > Add(uint32_t size, WifiTxVector txVector, enum WifiPreamble preamble, Time duration, double rxPower)
Add the packet-related signal to interference helper.
Definition: interference-helper.cc:150
ns3::InterferenceHelper::Event::Event
Event(uint32_t size, WifiTxVector txVector, enum WifiPreamble preamble, Time duration, double rxPower)
Create an Event with the given parameters.
Definition: interference-helper.cc:37
ns3::WIFI_PREAMBLE_LONG
Definition: wifi-preamble.h:32
ns3::WIFI_PREAMBLE_HT_GF
Definition: wifi-preamble.h:35
ns3::InterferenceHelper::CalculatePlcpHeaderPer
double CalculatePlcpHeaderPer(Ptr< const Event > event, NiChanges *ni) const
Calculate the error rate of the plcp header.
Definition: interference-helper.cc:335
ns3::InterferenceHelper::NiChange::GetDelta
double GetDelta(void) const
Return the power.
Definition: interference-helper.cc:120
ns3::WifiPhy::GetPlcpVhtSigA1Duration
static Time GetPlcpVhtSigA1Duration(WifiPreamble preamble)
Definition: wifi-phy.cc:195
ns3::Simulator::Now
static Time Now(void)
Return the current simulation virtual time.
Definition: simulator.cc:223
ns3::InterferenceHelper::Event::GetEndTime
Time GetEndTime(void) const
Return the end time of the signal.
Definition: interference-helper.cc:66
ns3::InterferenceHelper::Event::GetPreambleType
enum WifiPreamble GetPreambleType(void) const
Return the preamble type of the packet.
Definition: interference-helper.cc:96
ns3::InterferenceHelper::NotifyRxEnd
void NotifyRxEnd()
Notify that RX has ended.
Definition: interference-helper.cc:856
ns3::InterferenceHelper::NiChange::NiChange
NiChange(Time time, double delta)
Create a NiChange at the given time and the amount of NI change.
Definition: interference-helper.cc:107
ns3::InterferenceHelper::CalculateSnr
double CalculateSnr(double signal, double noiseInterference, uint32_t channelWidth) const
Calculate SNR (linear ratio) from the given signal power and noise+interference power.
Definition: interference-helper.cc:237
ns3::InterferenceHelper::Event::GetDuration
Time GetDuration(void) const
Return the duration of the signal.
Definition: interference-helper.cc:54
ns3::InterferenceHelper::SetNoiseFigure
void SetNoiseFigure(double value)
Set the noise figure.
Definition: interference-helper.cc:167
ns3::InterferenceHelper::Event::GetPayloadMode
WifiMode GetPayloadMode(void) const
Return the Wi-Fi mode used for the payload.
Definition: interference-helper.cc:90
NS_LOG_DEBUG
#define NS_LOG_DEBUG(msg)
Use NS_LOG to output a message of level LOG_DEBUG.
Definition: log.h:236
ns3::WifiPhy::GetPlcpHeaderDuration
static Time GetPlcpHeaderDuration(WifiTxVector txVector, WifiPreamble preamble)
Definition: wifi-phy.cc:282
ns3::InterferenceHelper::AppendEvent
void AppendEvent(Ptr< Event > event)
Append the given Event.
Definition: interference-helper.cc:214
ns3::MicroSeconds
Time MicroSeconds(uint64_t value)
Construct a Time in the indicated unit.
Definition: nstime.h:911
ns3::Now
Time Now(void)
create an ns3::Time instance which contains the current simulation time.
Definition: simulator.cc:330
ns3::InterferenceHelper::GetNoiseFigure
double GetNoiseFigure(void) const
Return the noise figure.
Definition: interference-helper.cc:173
ns3::WIFI_PREAMBLE_SHORT
Definition: wifi-preamble.h:33
ns3::WifiPhy::GetPlcpHtTrainingSymbolDuration
static Time GetPlcpHtTrainingSymbolDuration(WifiPreamble preamble, WifiTxVector txVector)
Definition: wifi-phy.cc:134
ns3::WifiPhy::GetPlcpVhtSigBDuration
static Time GetPlcpVhtSigBDuration(WifiPreamble preamble)
Definition: wifi-phy.cc:223
ns3::WifiPhy::GetPlcpPreambleDuration
static Time GetPlcpPreambleDuration(WifiTxVector txVector, WifiPreamble preamble)
Definition: wifi-phy.cc:346
ns3::WifiPhy::GetPlcpVhtSigA2Duration
static Time GetPlcpVhtSigA2Duration(WifiPreamble preamble)
Definition: wifi-phy.cc:209
ns3::WIFI_PREAMBLE_HT_MF
Definition: wifi-preamble.h:34