1 /* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */

     2 /*

     3  * Copyright (c) 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  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

    19  */

    20 #include "ideal-wifi-manager.h"

    21 #include "wifi-phy.h"

    22 #include "ns3/assert.h"

    23 #include "ns3/double.h"

    24 #include <math.h>

    25 

    26 #define noIDEAL_DEBUG 1

    27 

    28 #ifdef IDEAL_DEBUG

    29 #include <iostream>

    30 #  define TRACE(x) \

    31 std::cout << "IDEAL TRACE " << x << std::endl;

    32 #else

    33 #  define TRACE(x)

    34 #endif

    35 

    36 

    37 namespace ns3 {

    38 

    39 NS_OBJECT_ENSURE_REGISTERED (IdealWifiManager);

    40 

    41 TypeId 

    42 IdealWifiManager::GetTypeId (void)

    43 {

    44   static TypeId tid = TypeId ("IdealWifiManager")

    45     .SetParent<WifiRemoteStationManager> ()

    46     .AddConstructor<IdealWifiManager> ()

    47     .AddAttribute ("BerThreshold",

    48                    "The maximum Bit Error Rate acceptable at any transmission mode",

    49                    Double (10e-6),

    50                    MakeDoubleAccessor (&IdealWifiManager::m_ber),

    51                    MakeDoubleChecker<double> ())

    52     ;

    53   return tid;

    54 }

    55 

    56 IdealWifiManager::IdealWifiManager ()

    57 {}

    58 IdealWifiManager::~IdealWifiManager ()

    59 {}

    60 

    61 void 

    62 IdealWifiManager::SetupPhy (Ptr<WifiPhy> phy)

    63 {

    64   uint32_t nModes = phy->GetNModes ();

    65   for (uint32_t i = 0; i < nModes; i++) 

    66     {

    67       WifiMode mode = phy->GetMode (i);

    68       AddModeSnrThreshold (mode, phy->CalculateSnr (mode, m_ber));

    69     }

    70   

    71   WifiRemoteStationManager::SetupPhy (phy);

    72 }

    73 

    74 WifiRemoteStation *

    75 IdealWifiManager::CreateStation (void)

    76 {

    77   return new IdealWifiRemoteStation (this);

    78 }

    79 

    80 double 

    81 IdealWifiManager::GetSnrThreshold (WifiMode mode) const

    82 {

    83   for (Thresholds::const_iterator i = m_thresholds.begin (); i != m_thresholds.end (); i++) 

    84     {

    85       if (mode == i->second)

    86         {

    87           return i->first;

    88         }

    89     }

    90   NS_ASSERT (false);

    91   return 0.0;

    92 }

    93 

    94 void 

    95 IdealWifiManager::AddModeSnrThreshold (WifiMode mode, double snr)

    96 {

    97   m_thresholds.push_back (std::make_pair (snr,mode));

    98 }

    99 

   100 IdealWifiRemoteStation::IdealWifiRemoteStation (Ptr<IdealWifiManager> manager)

   101   : m_manager (manager),

   102     m_lastSnr (0.0)

   103 {}

   104 IdealWifiRemoteStation::~IdealWifiRemoteStation ()

   105 {}

   106 void 

   107 IdealWifiRemoteStation::ReportRxOk (double rxSnr, WifiMode txMode)

   108 {}

   109 void 

   110 IdealWifiRemoteStation::ReportRtsFailed (void)

   111 {}

   112 void 

   113 IdealWifiRemoteStation::ReportDataFailed (void)

   114 {}

   115 void 

   116 IdealWifiRemoteStation::ReportRtsOk (double ctsSnr, WifiMode ctsMode, double rtsSnr)

   117 {

   118   TRACE ("got cts for rts snr="<<rtsSnr);

   119   m_lastSnr = rtsSnr;

   120 }

   121 void 

   122 IdealWifiRemoteStation::ReportDataOk (double ackSnr, WifiMode ackMode, double dataSnr)

   123 {

   124   TRACE ("got cts for rts snr="<<dataSnr);

   125   m_lastSnr = dataSnr;

   126 }

   127 void 

   128 IdealWifiRemoteStation::ReportFinalRtsFailed (void)

   129 {}

   130 void 

   131 IdealWifiRemoteStation::ReportFinalDataFailed (void)

   132 {}

   133 

   134 WifiMode

   135 IdealWifiRemoteStation::DoGetDataMode (uint32_t size)

   136 {

   137   // We search within the Supported rate set the mode with the 

   138   // highest snr threshold possible which is smaller than m_lastSnr 

   139   // to ensure correct packet delivery.

   140   double maxThreshold = 0.0;

   141   WifiMode maxMode = m_manager->GetDefaultMode ();

   142   for (uint32_t i = 0; i < GetNSupportedModes (); i++)

   143     {

   144       WifiMode mode = GetSupportedMode (i);

   145       double threshold = m_manager->GetSnrThreshold (mode);

   146       if (threshold > maxThreshold && 

   147           threshold < m_lastSnr)

   148         {

   149           maxThreshold = threshold;

   150           maxMode = mode;

   151         }

   152     }

   153   return maxMode;

   154 }

   155 WifiMode

   156 IdealWifiRemoteStation::DoGetRtsMode (void)

   157 {

   158   // We search within the Basic rate set the mode with the highest 

   159   // snr threshold possible which is smaller than m_lastSnr to 

   160   // ensure correct packet delivery.

   161   double maxThreshold = 0.0;

   162   WifiMode maxMode = m_manager->GetDefaultMode ();

   163   for (uint32_t i = 0; i < m_manager->GetNBasicModes (); i++)

   164     {

   165       WifiMode mode = m_manager->GetBasicMode (i);

   166       double threshold = m_manager->GetSnrThreshold (mode);

   167       if (threshold > maxThreshold && 

   168           threshold < m_lastSnr)

   169         {

   170           maxThreshold = threshold;

   171           maxMode = mode;

   172         }

   173     }

   174   return maxMode;

   175 }

   176 Ptr<WifiRemoteStationManager>

   177 IdealWifiRemoteStation::GetManager (void) const

   178 {

   179   return m_manager;

   180 }

   181 

   182 } // namespace ns3