bsscheduler.cc

Ns2下Wimax的代码

/* This software was developed at the National Institute of Standards and
 * Technology by employees of the Federal Government in the course of
 * their official duties. Pursuant to title 17 Section 105 of the United
 * States Code this software is not subject to copyright protection and
 * is in the public domain.
 * NIST assumes no responsibility whatsoever for its use by other parties,
 * and makes no guarantees, expressed or implied, about its quality,
 * reliability, or any other characteristic.
 * <BR>
 * We would appreciate acknowledgement if the software is used.
 * <BR>
 * NIST ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION AND
 * DISCLAIM ANY LIABILITY OF ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING
 * FROM THE USE OF THIS SOFTWARE.
 * </PRE></P>
 * @author  rouil
 */

#include "bsscheduler.h"
#include "burst.h"
#include "dlburst.h"
#include "ulburst.h"
#include "random.h"
#include "wimaxctrlagent.h"
#include "mac802_16BS.h"

/**
 * Bridge to TCL for BSScheduler
 */
static class BSSchedulerClass : public TclClass {
public:
  BSSchedulerClass() : TclClass("WimaxScheduler/BS") {}
  TclObject* create(int, const char*const*) {
    return (new BSScheduler());
    
  }
} class_bsscheduler;

/*
 * Create a scheduler
 */
BSScheduler::BSScheduler () 
{
  debug2 ("BSScheduler created\n");
  default_mod_ = OFDM_BPSK_1_2;
  bind ("dlratio_", &dlratio_);

  //dlratio_ = DEFAULT_DL_RATIO;

  contention_size_ = MIN_CONTENTION_SIZE;

  nextDL_ = -1;
  nextUL_ = -1;
}
 
/**
 * Return the MAC casted to BSScheduler
 * @return The MAC casted to BSScheduler
 */
Mac802_16BS* BSScheduler::getMac()
{
  return (Mac802_16BS*)mac_;
}

/*
 * Interface with the TCL script
 * @param argc The number of parameter
 * @param argv The list of parameters
 */
int BSScheduler::command(int argc, const char*const* argv)
{
  if (argc == 3) {
    if (strcmp(argv[1], "set-default-modulation") == 0) {
      if (strcmp(argv[2], "OFDM_BPSK_1_2") == 0)
	default_mod_ = OFDM_BPSK_1_2;
      else if (strcmp(argv[2], "OFDM_QPSK_1_2") == 0)
	default_mod_ = OFDM_QPSK_1_2;
      else if (strcmp(argv[2], "OFDM_QPSK_3_4") == 0)
	default_mod_ = OFDM_QPSK_3_4;
      else if (strcmp(argv[2], "OFDM_16QAM_1_2") == 0)
	default_mod_ = OFDM_16QAM_1_2;
      else if (strcmp(argv[2], "OFDM_16QAM_3_4") == 0)
	default_mod_ = OFDM_16QAM_3_4;
      else if (strcmp(argv[2], "OFDM_64QAM_2_3") == 0)
	default_mod_ = OFDM_64QAM_2_3;
      else if (strcmp(argv[2], "OFDM_64QAM_3_4") == 0)
	default_mod_ = OFDM_64QAM_3_4;
      else
	return TCL_ERROR;
      return TCL_OK;
    }
    else if (strcmp(argv[1], "set-contention-size") == 0) {
      contention_size_ = atoi (argv[2]);
      assert (contention_size_>=0);
      return TCL_OK;      
    }
  }
  return TCL_ERROR;
}

/**
 * Initializes the scheduler
 */
void BSScheduler::init ()
{
  WimaxScheduler::init();

  // If the user did not set the profiles by hand, let's do it
  // automatically
  if (getMac()->getMap()->getDlSubframe()->getProfile (DIUC_PROFILE_1)==NULL) {
    Profile *p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_BPSK_1_2);
    p->setIUC (DIUC_PROFILE_1);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_QPSK_1_2);
    p->setIUC (DIUC_PROFILE_2);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_QPSK_3_4);
    p->setIUC (DIUC_PROFILE_3);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_16QAM_1_2);
    p->setIUC (DIUC_PROFILE_4);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_16QAM_3_4);
    p->setIUC (DIUC_PROFILE_5);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_64QAM_2_3);
    p->setIUC (DIUC_PROFILE_6);
    p = getMac()->getMap()->getDlSubframe()->addProfile ((int)round((getMac()->getPhy()->getFreq()/1000)), OFDM_64QAM_3_4);
    p->setIUC (DIUC_PROFILE_7);

    p = getMac()->getMap()->getUlSubframe()->addProfile (0, default_mod_);
    p->setIUC (UIUC_INITIAL_RANGING);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, default_mod_);
    p->setIUC (UIUC_REQ_REGION_FULL);  

    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_BPSK_1_2);
    p->setIUC (UIUC_PROFILE_1);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_QPSK_1_2);
    p->setIUC (UIUC_PROFILE_2);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_QPSK_3_4);
    p->setIUC (UIUC_PROFILE_3);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_16QAM_1_2);
    p->setIUC (UIUC_PROFILE_4);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_16QAM_3_4);
    p->setIUC (UIUC_PROFILE_5);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_64QAM_2_3);
    p->setIUC (UIUC_PROFILE_6);
    p = getMac()->getMap()->getUlSubframe()->addProfile (0, OFDM_64QAM_3_4);
    p->setIUC (UIUC_PROFILE_7);
  }

  //init contention slots
  ContentionSlot *slot = getMac()->getMap()->getUlSubframe()->getRanging ();
  slot->setSize (getInitRangingopportunity ());
  slot->setBackoff_start (getMac()->macmib_.rng_backoff_start);
  slot->setBackoff_stop (getMac()->macmib_.rng_backoff_stop);
  
  slot = getMac()->getMap()->getUlSubframe()->getBw_req ();
  slot->setSize (getBWopportunity ());
  slot->setBackoff_start (getMac()->macmib_.bw_backoff_start);
  slot->setBackoff_stop (getMac()->macmib_.rng_backoff_stop);

}

/**
 * Compute and return the bandwidth request opportunity size
 * @return The bandwidth request opportunity size
 */
int BSScheduler::getBWopportunity ()
{
  int nbPS = BW_REQ_PREAMBLE * getMac()->getPhy()->getSymbolPS();
  //add PS for carrying header
  nbPS += (int) round((getMac()->getPhy()->getTrxTime (HDR_MAC802_16_SIZE, getMac()->getMap()->getUlSubframe()->getProfile(UIUC_REQ_REGION_FULL)->getEncoding())/getMac()->getPhy()->getPS ()));
  //printf ("BWopportunity size=%d\n", nbPS);
  return nbPS;
}

/**
 * Compute and return the initial ranging opportunity size
 * @return The initial ranging opportunity size
 */
int BSScheduler::getInitRangingopportunity ()
{
  int nbPS = INIT_RNG_PREAMBLE * getMac()->getPhy()->getSymbolPS();
  //add PS for carrying header
  nbPS += (int) round((getMac()->getPhy()->getTrxTime (RNG_REQ_SIZE+HDR_MAC802_16_SIZE, getMac()->getMap()->getUlSubframe()->getProfile(UIUC_INITIAL_RANGING)->getEncoding())/getMac()->getPhy()->getPS ()));
  //printf ("Init ranging opportunity size=%d\n", nbPS);
  return nbPS;  
}

/**
 * Schedule bursts/packets
 */
void BSScheduler::schedule ()
{
  //The scheduler will perform the following steps:
  //1-Clear DL map
  //2-Allocate Burst for Broadcast message
  //3-Pick Unicast bursts for Downlink (Best Effort) in a RR fashion
  //4-Clear UL map
  //5-Allocate contention slots for initial ranging
  //6-Allocate contention slots for bandwidth requests
  //7-Allocate unicast burst for Uplink according to bandwidth requests received (RR fashion)

  Packet *p;
  struct hdr_cmn *ch;
  double txtime; //tx time for some data (in second)
  int txtime_s;  //number of symbols used to transmit the data
  DlBurst *db;
  PeerNode *peer;

  OFDMPhy *phy = mac_->getPhy();
  //variables for scheduling
  FrameMap *map = mac_->getMap();
  int nbPS = (int) floor((mac_->getFrameDuration()/phy->getPS()));
  assert (nbPS*phy->getPS()<=mac_->getFrameDuration()); //check for rounding errors
  int nbPS_left = nbPS - mac_->phymib_.rtg - mac_->phymib_.ttg;
  int nbSymbols = (int) floor((phy->getPS()*nbPS_left)/phy->getSymbolTime());
  assert (nbSymbols*phy->getSymbolTime()+(mac_->phymib_.rtg + mac_->phymib_.ttg)*phy->getPS() < mac_->getFrameDuration());
  int maxdlduration = (int) (nbSymbols / (1.0/dlratio_)); //number of symbols for downlink
  int dlduration = DL_PREAMBLE;                             //number of symbols currently used for downlink
  int nbdlbursts = 0;
  int maxulduration = nbSymbols - maxdlduration;            //number of symbols for uplink
  int ulduration = 0;                                       //number of symbols currently used for uplink
  int nbulpdus = 0;

  //printf ("%d %9f\n",phy->getSymbolPS(), (nbSymbols*phy->getSymbolPS()+mac_->phymib_.rtg + mac_->phymib_.ttg)*phy->getPS());

  assert ((nbSymbols*phy->getSymbolPS()+mac_->phymib_.rtg + mac_->phymib_.ttg)*phy->getPS()< mac_->getFrameDuration());

  assert (maxdlduration*phy->getSymbolTime()+mac_->phymib_.rtg*phy->getPS()+maxulduration*phy->getSymbolTime()+mac_->phymib_.ttg*phy->getPS() < mac_->getFrameDuration());
  

  debug2 ("Frame: duration=%f, PSduration=%e, symboltime=%e, nbPS=%d, rtg=%d, ttg=%d, PSleft=%d, nbSymbols=%d, ", \
	  mac_->getFrameDuration(), phy->getPS(), phy->getSymbolTime(), nbPS, mac_->phymib_.rtg, mac_->phymib_.ttg, nbPS_left, nbSymbols);
  debug2 ("maxdlduration=%d, maxulduration=%d\n",maxdlduration, maxulduration);

  map->getDlSubframe()->getPdu()->removeAllBursts();
  //1-First burst for broadcast messages are using DIUC_PROFILE_4
  db = (DlBurst*) map->getDlSubframe()->getPdu ()->addBurst (nbdlbursts++);
  db->setCid ( BROADCAST_CID );
  db->setIUC (map->getDlSubframe()->getProfile (DIUC_PROFILE_4)->getIUC());
  db->setStarttime (dlduration); //after preamble and fch
  db->setPreamble(true); //this is the first burst after preamble
  
  //time to send DL_MAP and UL_MAP
  txtime = phy->getTrxSymbolTime (2*sizeof (struct gen_mac_header_t)+sizeof (struct mac802_16_dl_map_frame)+sizeof (struct mac802_16_ul_map_frame), map->getDlSubframe()->getProfile (db->getIUC())->getEncoding());
  txtime_s = (int) round(txtime/phy->getSymbolTime ()); //in units of symbol
  if ((dlduration+txtime_s) > maxdlduration) {
    fprintf (stderr, "Error: Not enough symbols on the downlink subframe to send synchronization messages\n");
    fprintf (stderr, "       maxdlduration=%d, needed=%d\n", maxdlduration, dlduration+txtime_s);
    fprintf (stderr, "       Consider incrementing the dlratio_ or using a better modulation\n");
    exit(0);
  }
  
  db->setDuration (txtime_s); //enough to send DL_MAP...
  
  //check if we have to add DCD and/or UCD to transmit and increase burst size if
  //necessary
  if (getMac()->sendDCD || map->getDlSubframe()->getCCC()!= getMac()->dlccc_) {
    p = map->getDCD();
    ch = HDR_CMN(p);
    txtime = phy->getTrxTime (ch->size(), map->getDlSubframe()->getProfile (db->getIUC())->getEncoding());
    ch->txtime() = txtime;
    txtime_s = (int) ceil(txtime/phy->getSymbolTime ()); //in units of symbol
    assert ((dlduration+db->getDuration()+txtime_s) <= maxdlduration); //if this occurs, increase dlratio
    db->setDuration (db->getDuration()+txtime_s);
  }
  if (getMac()->sendUCD || map->getUlSubframe()->getCCC()!= getMac()->ulccc_) {
    p = map->getUCD();
    ch = HDR_CMN(p);
    txtime = phy->getTrxTime (ch->size(), map->getDlSubframe()->getProfile (db->getIUC())->getEncoding());