/src/linklayer/radio/Ieee80211aRadioModel.cc

https://github.com/Sorouri/inetmanet · C++ · 455 lines · 293 code · 85 blank · 77 comment · 87 complexity · 2040f5604c654cb035c60ee47201f2bf MD5 · raw file 

    

  1. //

    2. 

  2. // Copyright (C) 2006 Andras Varga, Levente Meszaros

    3. 

  3. // Based on the Mobility Framework's SnrEval by Marc Loebbers

    4. 

  4. //

    5. 

  5. // This program is free software; you can redistribute it and/or

    6. 

  6. // modify it under the terms of the GNU General Public License

    7. 

  7. // as published by the Free Software Foundation; either version 2

    8. 

  8. // of the License, or (at your option) any later version.

    9. 

  9. //

    10. 

  10. // This program is distributed in the hope that it will be useful,

    11. 

  11. // but WITHOUT ANY WARRANTY; without even the implied warranty of

    12. 

  12. // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    13. 

  13. // GNU General Public License for more details.

    14. 

  14. //

    15. 

  15. // You should have received a copy of the GNU General Public License

    16. 

  16. // along with this program; if not, write to the Free Software

    17. 

  17. // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

    18. 

  18. //

    19. 

  19. 

    20. 

  20. #define IEEE80211A

    21. 

  21. #include "Ieee80211aRadioModel.h"

    22. 

  22. #include "Ieee80211aConsts.h"

    23. 

  23. 

    24. 

  24. #include "FWMath.h"

    25. 

  25. 

    26. 

  26. #include "Modulation.h"

    27. 

  27. 

    28. 

  28. 

    29. 

  29. /* added by Sorin Cocorada sorin.cocorada@gmail.com*/

    30. 

  30. static const unsigned short comb_calc[15][15]=

    31. 

  31. {

    32. 

  32. {    1,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0 },

    33. 

  33. {    2,    1,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0 },

    34. 

  34. {    3,    3,    1,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0 },

    35. 

  35. {    4,    6,    4,    1,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0 },

    36. 

  36. {    5,   10,   10,    5,    1,    0,    0,    0,    0,    0,    0,    0,    0,    0 },

    37. 

  37. {    6,   15,   20,   15,    6,    1,    0,    0,    0,    0,    0,    0,    0,    0 },

    38. 

  38. {    7,   21,   35,   35,   21,    7,    1,    0,    0,    0,    0,    0,    0,    0 },

    39. 

  39. {    8,   28,   56,   70,   56,   28,    8,    1,    0,    0,    0,    0,    0,    0 },

    40. 

  40. {    9,   36,   84,  126,  126,   84,   36,    9,    1,    0,    0,    0,    0,    0 },

    41. 

  41. {   10,   45,  120,  210,  252,  210,  120,   45,   10,    1,    0,    0,    0,    0 },

    42. 

  42. {   11,   55,  165,  330,  462,  462,  330,  165,   55,   11,    1,    0,    0,    0 },

    43. 

  43. {   12,   66,  220,  495,  792,  924,  792,  495,  220,   66,   12,    1,    0,    0 },

    44. 

  44. {   13,   78,  286,  715, 1287, 1716, 1716, 1287,  715,  286,   78,   13,    1,    0 },

    45. 

  45. {   14,   91,  364, 1001, 2002, 3003, 3432, 3003, 2002, 1001,  364,   91,   14,    1 }

    46. 

  46. };

    47. 

  47. 

    48. 

  48. /*

    49. 

  49. int comb(int n,int k){

    50. 

  50.     int p1=1, p2=1,i;

    51. 

  51.     for(i=0; i<=k-1; i++)

    52. 

  52.         p1=p1*(n-i);

    53. 

  53.     for(i=2; i<=k; i++)

    54. 

  54.         p2=p2*i;

    55. 

  55.     return p1/p2;

    56. 

  56. }

    57. 

  57. */

    58. 

  58. 

    59. 

  59. static unsigned short comb(int n,int k)

    60. 

  60. {

    61. 

  61. //    ASSERT((n>=1) && (n<=14) (k>=1) && (k<=14));

    62. 

  62.     return comb_calc[n-1][k-1];

    63. 

  63. }

    64. 

  64. 

    65. 

  65. 

    66. 

  66. static double Pd(int d, double Pb)

    67. 

  67. {

    68. 

  68.     long double sum=0.0;

    69. 

  69.     int k;

    70. 

  70.     if(d%2 == 1){

    71. 

  71.         for(k=(d+1)/2; k<=d; k++)

    72. 

  72.             sum+=comb(d,k)*pow(Pb,k)*pow(1.0-Pb, d-k);

    73. 

  73.     }

    74. 

  74.     else{

    75. 

  75.         sum=0.5*comb(d,d/2)*pow(Pb, d/2)*pow(1.0-Pb,d/2);

    76. 

  76.         for(k=d/2+1; k<=d; k++)

    77. 

  77.              sum+=comb(d,k)*pow(Pb,k)*pow(1.0-Pb, d-k);

    78. 

  78.     }

    79. 

  79.     //printf("prob=%f d=%d sum=%f \n",Pb,d, sum);

    80. 

  80.     return sum;

    81. 

  81. 

    82. 

  82.     //return pow(4*Pb*(1-Pb), d/2);

    83. 

  83. }

    84. 

  84. 

    85. 

  85. 

    86. 

  86. static double Pb(int rate, double prob)

    87. 

  87. {

    88. 

  88.     long double probc;

    89. 

  89.     switch(rate){

    90. 

  90. 

    91. 

  91.     case 1:

    92. 

  92.     //11, 0, 38, 0, 193, 0, 1331, 0, 7275, 0, 40406, 0, 234969, 0, 1337714, 0, 7594819, 0, 433775588, 0,

    93. 

  93.     probc=11*Pd(10,prob) + 38*Pd(12,prob) + 193*Pd(14,prob);//+1331*Pd(16,prob);

    94. 

  94.     break;

    95. 

  95. 

    96. 

  96.     case 2:

    97. 

  97.     //1, 16, 48, 158, 642, 2435, 9174, 34701, 131533, 499312,

    98. 

  98.     probc=Pd(6,prob)+16*Pd(7,prob)+48*Pd(8,prob);//+158*Pd(9,prob)+642*Pd(10,prob)

    99. 

  99.     //+2435*Pd(11,prob)+ 9174*Pd(12,prob)+34701*Pd(13,prob)+131533*Pd(14,prob)+499312*Pd(15,prob);

    100. 

  100.     break;

    101. 

  101. 

    102. 

  102.     case 3:

    103. 

  103.     //(8, 31, 160, 892, 4512, 23297, 120976, 624304, 3229885, 16721329,

    104. 

  104.     probc=8*Pd(5,prob)+31*Pd(6,prob)+150*Pd(7,prob);//+892*Pd(8,prob)+4512*Pd(9,prob)

    105. 

  105.     //+23297*Pd(10,prob)+120976*Pd(11,prob)+624304*Pd(12,prob)+ 3229885*Pd(13,prob)+ 16721329*Pd(14,prob);

    106. 

  106.     break;

    107. 

  107.     default:

    108. 

  108.     ;

    109. 

  109.     }

    110. 

  110. 

    111. 

  111.     return probc;

    112. 

  112. }

    113. 

  113. 

    114. 

  114. 

    115. 

  115. static double ber_bpsk(double snir, double bandwidth, double bitrate, char channelModel)

    116. 

  116. {

    117. 

  117.     double y=snir*bandwidth/bitrate;

    118. 

  118. 

    119. 

  119.     if(channelModel=='r')//Rayleigh

    120. 

  120.         return 0.5*(1.0-sqrt(y/(1.0+y)));

    121. 

  121. 

    122. 

  122.     return 0.5*erfc(sqrt(y));//awgn

    123. 

  123. }

    124. 

  124. 

    125. 

  125. static double ber_qpsk(double snir, double bandwidth, double bitrate, char channelModel)

    126. 

  126. {

    127. 

  127.     double y=snir*bandwidth/bitrate;

    128. 

  128. 

    129. 

  129.     if(channelModel=='r')//Rayleigh

    130. 

  130.         return 0.5*(1.0-sqrt(y/(1.0+y)));

    131. 

  131.     return 0.5*erfc(sqrt(y));//awgn

    132. 

  132. }

    133. 

  133. 

    134. 

  134. static double ber_16qam(double snir, double bandwidth, double bitrate, char channelModel)

    135. 

  135. {

    136. 

  136.     double y=snir*bandwidth/bitrate;

    137. 

  137. 

    138. 

  138.     if(channelModel=='r')//Rayleigh

    139. 

  139.     return ( 5.0/8.0-3.0/8.0*sqrt(2.0*y/(5.0+2.0*y))-1.0/4.0*sqrt(18.0*y/(5.0+18.0*y)) );

    140. 

  140.     return ( 0.375*erfc(sqrt(0.4*y))+0.25*erfc(3.0*sqrt(0.4*y)) );//awgn

    141. 

  141. 

    142. 

  142. }

    143. 

  143. 

    144. 

  144. static double ber_64qam(double snir, double bandwidth, double bitrate, char channelModel)

    145. 

  145. {

    146. 

  146.     double y=snir*bandwidth/bitrate;

    147. 

  147. 

    148. 

  148.     if(channelModel=='r')//Rayleigh

    149. 

  149.         return ( 13.0/24.0-7.0/24.0*sqrt(y/(7.0+y))-1.0/4.0*sqrt(9.0*y/(7.0+9.0*y)) );

    150. 

  150.         return 7.0/24.0*erfc(sqrt(y/7.0))+0.25*erfc(3.0*sqrt(y/7.0));//awgn

    151. 

  151. }

    152. 

  152. 

    153. 

  153. 

    154. 

  154. /* end added by Sorin Cocorada sorin.cocorada@gmail.com*/

    155. 

  155. 

    156. 

  156. 

    157. 

  157. Register_Class(Ieee80211aRadioModel);

    158. 

  158. 

    159. 

  159. Ieee80211aRadioModel::~Ieee80211aRadioModel()

    160. 

  160. {

    161. 

  161.     if(phyOpMode=='a')

    162. 

  162.     {

    163. 

  163.         for (ModesCI j = modes.begin (); j != modes.end (); j++) {

    164. 

  164.             delete (*j);

    165. 

  165.         }

    166. 

  166.         modes.erase (modes.begin (), modes.end ());

    167. 

  167. 

    168. 

  168.         if (IS_ERROR_MASK_GENERATED)

    169. 

  169.             fclose(error_masks);

    170. 

  170.     }

    171. 

  171. }

    172. 

  172. 

    173. 

  173. void Ieee80211aRadioModel::initializeFrom(cModule *radioModule)

    174. 

  174. {

    175. 

  175.     snirThreshold = dB2fraction(radioModule->par("snirThreshold"));

    176. 

  176. 	//snirThreshold = dB2fraction(4);

    177. 

  177. 

    178. 

  178.     phyOpMode = radioModule->hasPar("phyOpMode") ? radioModule->par("phyOpMode") : 'b';

    179. 

  179.     if (phyOpMode==1)

    180. 

  180.           phyOpMode='b';

    181. 

  181.     else if (phyOpMode==2)

    182. 

  182.           phyOpMode='g';

    183. 

  183.     else if (phyOpMode==3)

    184. 

  184.           phyOpMode='a';

    185. 

  185.    else

    186. 

  186.          phyOpMode='b';

    187. 

  187. 

    188. 

  188.     channelModel = radioModule->hasPar("channelModel") ? radioModule->par("channelModel") : 'r';

    189. 

  189. 

    190. 

  190.     if (channelModel==1)

    191. 

  191.           channelModel='r';

    192. 

  192.     else if (channelModel==2)

    193. 

  193.           channelModel='a';

    194. 

  194.     else

    195. 

  195.           channelModel='r';

    196. 

  196. 

    197. 

  197. 

    198. 

  198.     snirVector.setName("snirVector");

    199. 

  199.     perVector.setName("PER");

    200. 

  200. 

    201. 

  201. 	i=0;

    202. 

  202. 

    203. 

  203.     if(phyOpMode=='a')

    204. 

  204.     {

    205. 

  205.         configure80211a();

    206. 

  206.         error_masks = 0;

    207. 

  207. 

    208. 

  208.         if (IS_ERROR_MASK_GENERATED)

    209. 

  209.         {

    210. 

  210. 	        char str[80];

    211. 

  211. 	        sprintf(str,"%s%i%s","error_masks",(int)radioModule->par("ID"),".dat");

    212. 

  212. 			error_masks= fopen(str, "w+");

    213. 

  213. 			EV<<"Generation mask file : "<<str<<endl;

    214. 

  214.         }

    215. 

  215.     }

    216. 

  216. }

    217. 

  217. 

    218. 

  218. double Ieee80211aRadioModel::calculateDuration(AirFrame *airframe)

    219. 

  219. {

    220. 

  220.     double duration = 0;

    221. 

  221. 

    222. 

  222.     if(phyOpMode=='a')

    223. 

  223.         duration= (16+airframe->getBitLength()*8+6)/airframe->getBitrate()+PLCP_PREAMBLE_DELAY+PLCP_SIGNAL_DELAY+T_SYM/2;

    224. 

  224.     else if(phyOpMode=='g')

    225. 

  225.         duration=4*ceil((16+airframe->getBitLength()+6)/(airframe->getBitrate()/1e6*4))*1e-6 + 26e-6;

    226. 

  226.     else

    227. 

  227.     // The physical layer header is sent with 1Mbit/s and the rest with the frame's bitrate

    228. 

  228.         duration=airframe->getBitLength()/airframe->getBitrate() + 192/BITRATE_HEADER;

    229. 

  229.     EV<<"Radio:frameDuration="<<duration*1e6<<"us("<<airframe->getBitLength()<<"bits)"<<endl;

    230. 

  230.     return duration;

    231. 

  231. }

    232. 

  232. 

    233. 

  233. bool Ieee80211aRadioModel::isReceivedCorrectly(AirFrame *airframe, const SnrList& receivedList)

    234. 

  234. {

    235. 

  235. 

    236. 

  236. //    unsigned char packet_ok;

    237. 

  237. //    unsigned long length;

    238. 

  238.     unsigned char *buffer=NULL;

    239. 

  239. 

    240. 

  240. //	buffer=(unsigned char*)malloc(airframe->getBitLength()*sizeof(unsigned char));

    241. 

  241.     if (buffer)

    242. 

  242.     for(int j=0;j<airframe->getBitLength();j++)

    243. 

  243.  	//	buffer[i] = airframe->getBuffer(i);

    244. 

  244. 	    buffer[j] = 0;///Error, there is no getBuffer() to airframe ;

    245. 

  245. 

    246. 

  246. 

    247. 

  247. //   length = airframe->getBitLength()+PHY_HEADER_LENGTH_A+2;

    248. 

  248. 

    249. 

  249. //    length = length/8;

    250. 

  250. //    printf("\n  length = %d length sans phy=%d",length,airframe->getBitLength());

    251. 

  251. 

    252. 

  252. 	// calculate snirMin

    253. 

  253.     double snirMin = receivedList.begin()->snr;

    254. 

  254.     for (SnrList::const_iterator iter = receivedList.begin(); iter != receivedList.end(); iter++)

    255. 

  255.         if (iter->snr < snirMin)

    256. 

  256.             snirMin = iter->snr;

    257. 

  257. 

    258. 

  258.     cPacket *frame = airframe->getEncapsulatedMsg();

    259. 

  259.     EV << "packet (" << frame->getClassName() << ")" << frame->getName() << " (" << frame->info() << ") snrMin=" << snirMin << endl;

    260. 

  260. 

    261. 

  261.     if(i%1000==0){

    262. 

  262.         snirVector.record(10*log10(snirMin));

    263. 

  263.         i=0;

    264. 

  264.     }

    265. 

  265.     i++;

    266. 

  266. 

    267. 

  267.     if (snirMin <= snirThreshold)

    268. 

  268.     {

    269. 

  269.         // if snir is too low for the packet to be recognized

    270. 

  270.         EV << "COLLISION! Packet got lost. Noise only\n";

    271. 

  271.         return false;

    272. 

  272.     }

    273. 

  273.     else if (isPacketOK(buffer,snirMin, airframe->getBitLength(), airframe->getBitrate()))

    274. 

  274.     {

    275. 

  275.         EV << "packet was received correctly, it is now handed to upper layer...\n";

    276. 

  276. 	   // for(int i=0;i<airframe->getBitLength();i++)

    277. 

  277. 	//	    airframe->setBuffer(i,buffer[i]);

    278. 

  278.         return true;

    279. 

  279.     }

    280. 

  280.     else

    281. 

  281.     {

    282. 

  282.         EV << "Packet has BIT ERRORS! It is lost!\n";

    283. 

  283.         return false;

    284. 

  284.     }

    285. 

  285.     if (buffer)

    286. 

  286. 	free(buffer);

    287. 

  287. }

    288. 

  288. 

    289. 

  289. 

    290. 

  290. //static unsigned char phy_header[PHY_HEADER_LENGTH_A];

    291. 

  291. 

    292. 

  292. bool Ieee80211aRadioModel::isPacketOK(unsigned char *buffer, double snirMin, int length, double bitrate)

    293. 

  293. {

    294. 

  294.     double berHeader, berMPDU;

    295. 

  295. 

    296. 

  296.     if(phyOpMode=='b')

    297. 

  297.     {

    298. 

  298.         berHeader = 0.5 * exp(-snirMin * BANDWIDTH / BITRATE_HEADER);

    299. 

  299. 

    300. 

  300.         // if PSK modulation

    301. 

  301.         if (bitrate == 1E+6 || bitrate == 2E+6)

    302. 

  302.             berMPDU = 0.5 * exp(-snirMin * BANDWIDTH / bitrate);

    303. 

  303.         // if CCK modulation (modeled with 16-QAM)

    304. 

  304.        else if (bitrate == 5.5E+6)

    305. 

  305.           berMPDU = 0.5 * (1 - 1 / sqrt(pow(2.0, 4))) * erfc(snirMin * BANDWIDTH / bitrate);

    306. 

  306.     else if(bitrate == 11E+6)                        // CCK, modelled with 256-QAM

    307. 

  307.         berMPDU = 0.25 * (1 - 1 / sqrt(pow(2.0, 8))) * erfc(snirMin * BANDWIDTH / bitrate);

    308. 

  308. 

    309. 

  309.     }

    310. 

  310. #if 0

    311. 

  311.     else if(phyOpMode=='a')

    312. 

  312.     {

    313. 

  313.         double per, psr = 1;

    314. 

  314. 		unsigned char packet_ok=1;

    315. 

  315. 

    316. 

  316.         if (IS_ERROR_MASK_GENERATED) fprintf(error_masks,"]\n");

    317. 

  317.         psr = 1;

    318. 

  318.         EV<<"PHY_HEADER_LENGTH"<<PHY_HEADER_LENGTH_A<<endl;

    319. 

  319.         //psr *= getMode(bitrate)->getChunkSuccessRate (snirMin, PHY_HEADER_LENGTH_A, error_masks, HEADER_BITRATE);

    320. 

  320.         //psr *= getMode(bitrate)->getChunkSuccessRate (snirMin, length, error_masks, bitrate);

    321. 

  321. 		psr *= getMode(bitrate)->getChunkSuccessRate (snirMin, length, buffer, bitrate);

    322. 

  322.         per = 1- psr;

    323. 

  323. 

    324. 

  324.         if(i%100==0) perVector.record(per);

    325. 

  325. 

    326. 

  326. 	    for(int i=0;i<PHY_HEADER_LENGTH_A;i++)

    327. 

  327. 	       if(phy_header[i]!=0)

    328. 

  328. 		       return(false);

    329. 

  329. 

    330. 

  330.         /*double rand = dblrand();

    331. 

  331.         if (rand > per)

    332. 

  332.             return (true);

    333. 

  333.         //if no error

    334. 

  334.         else

    335. 

  335.             return (false);

    336. 

  336. 		*/

    337. 

  337. 	    return (true);

    338. 

  338.     }

    339. 

  339.     else if (phyOpMode=='g')

    340. 

  340. #endif

    341. 

  341.     else if ((phyOpMode=='g') || (phyOpMode=='a'))

    342. 

  342.     {

    343. 

  343.     //802.11g rates

    344. 

  344.     //PLCP Header 24bits, BPSK, r=1/2, 6Mbps

    345. 

  345.     berHeader=ber_bpsk(snirMin, BANDWIDTH , 6E+6, channelModel);

    346. 

  346.     berHeader=Pb(1, berHeader);

    347. 

  347. 

    348. 

  348. 

    349. 

  349.     switch((int)bitrate){//added by Sorin Cocorada

    350. 

  350. 

    351. 

  351.         case (int)(6E+6)://6Mbps, r=1/2, BPSK

    352. 

  352.             berMPDU=ber_bpsk(snirMin, BANDWIDTH , bitrate, channelModel);

    353. 

  353.             berMPDU=Pb(1, berMPDU);

    354. 

  354.         break;

    355. 

  355. 

    356. 

  356.         case (int)(9E+6)://9Mbps, r=3/4, BPSK

    357. 

  357.             berMPDU=ber_bpsk(snirMin, BANDWIDTH , bitrate, channelModel);

    358. 

  358.             berMPDU=Pb(3, berMPDU);

    359. 

  359.         break;

    360. 

  360. 

    361. 

  361.         case (int)(12E+6)://12Mbps, r=1/2, QPSK

    362. 

  362.             berMPDU=ber_qpsk(snirMin, BANDWIDTH , bitrate, channelModel);

    363. 

  363.             berMPDU=Pb(1, berMPDU);

    364. 

  364.         break;

    365. 

  365. 

    366. 

  366.         case (int)(18E+6)://18Mbps, r=3/4, QPSK

    367. 

  367.             berMPDU=ber_qpsk(snirMin, BANDWIDTH , bitrate, channelModel);

    368. 

  368.             berMPDU=Pb(3, berMPDU);

    369. 

  369.         break;

    370. 

  370. 

    371. 

  371.         case (int)(24E+6)://24Mbps, r=1/2, 16QAM

    372. 

  372.             berMPDU=ber_16qam(snirMin, BANDWIDTH , bitrate, channelModel);

    373. 

  373.             berMPDU=Pb(1, berMPDU);

    374. 

  374.         break;

    375. 

  375. 

    376. 

  376.         case (int)(36E+6)://36Mbps, r=3/4, 16QAM

    377. 

  377.             berMPDU=ber_16qam(snirMin, BANDWIDTH , bitrate, channelModel);

    378. 

  378.             berMPDU=Pb(3, berMPDU);

    379. 

  379.         break;

    380. 

  380. 

    381. 

  381.         case (int)(48E+6)://48Mbps, r=2/3, 64QAM

    382. 

  382.             berMPDU=ber_64qam(snirMin, BANDWIDTH , bitrate, channelModel);

    383. 

  383.             berMPDU=Pb(2, berMPDU);

    384. 

  384.         break;

    385. 

  385. 

    386. 

  386.         case (int)(54E+6)://54Mbps, r=3/4, 64QAM

    387. 

  387.             berMPDU=ber_64qam(snirMin, BANDWIDTH , bitrate, channelModel);

    388. 

  388.             berMPDU=Pb(3, berMPDU);

    389. 

  389.         break;

    390. 

  390. 

    391. 

  391.         default:

    392. 

  392.             berMPDU=0;

    393. 

  393.         }

    394. 

  394. 

    395. 

  395.     }

    396. 

  396. 

    397. 

  397.     // probability of no bit error in the PLCP header

    398. 

  398.     double headerNoError;

    399. 

  399.     // if(phyOpMode=='g')//added by Sorin Cocorada

    400. 

  400.     if ((phyOpMode=='g') || (phyOpMode=='a'))//added by Sorin Cocorada

    401. 

  401.         headerNoError = pow(1.0 - berHeader, 24);//PLCP Header 24bit(without SERVICE), 6Mbps

    402. 

  402.     else

    403. 

  403.     headerNoError = pow(1.0 - berHeader, HEADER_WITHOUT_PREAMBLE);

    404. 

  404. 

    405. 

  405.     // probability of no bit error in the MPDU

    406. 

  406.     double MpduNoError = pow(1.0 - berMPDU, length);

    407. 

  407.     EV << "berHeader: " << berHeader << " berMPDU: " <<berMPDU <<" length: "<<length<<" PER: "<<1-MpduNoError<<endl;

    408. 

  408.     double rand = dblrand();

    409. 

  409. 

    410. 

  410.     if (rand > headerNoError)

    411. 

  411.         return false; // error in header

    412. 

  412.     else if (dblrand() > MpduNoError)

    413. 

  413.         return false;  // error in MPDU

    414. 

  414.     else

    415. 

  415.         return true; // no error

    416. 

  416. }

    417. 

  417. 

    418. 

  418. double Ieee80211aRadioModel::dB2fraction(double dB)

    419. 

  419. {

    420. 

  420.     return pow(10.0, (dB / 10));

    421. 

  421. }

    422. 

  422. 

    423. 

  423. void Ieee80211aRadioModel::addTransmissionMode (TransmissionMode *mode)

    424. 

  424. {

    425. 

  425.     modes.push_back (mode);

    426. 

  426. }

    427. 

  427. 

    428. 

  428. TransmissionMode * Ieee80211aRadioModel::getMode (double rate) const

    429. 

  429. {

    430. 

  430.     //EV<<" getMode "<< rate<<endl;

    431. 

  431.     int mode;

    432. 

  432.     if (rate == 6E+6)       mode = 0;

    433. 

  433.     else if (rate == 9E+6)  mode = 1;

    434. 

  434.     else if (rate == 12E+6) mode = 2;

    435. 

  435.     else if (rate == 18E+6) mode = 3;

    436. 

  436.     else if (rate == 24E+6) mode = 4;

    437. 

  437.     else if (rate == 36E+6) mode = 5;

    438. 

  438.     else if (rate == 48E+6) mode = 6;

    439. 

  439.     else if (rate == 54E+6) mode = 7;

    440. 

  440.     return modes[mode];

    441. 

  441. }

    442. 

  442. 

    443. 

  443. void Ieee80211aRadioModel::configure80211a (void)

    444. 

  444. {

    445. 

  445.    // addTransmissionMode (new FecBpskMode (20e6,  6000000, 0.5 ));

    446. 

  446. //    addTransmissionMode (new FecBpskMode (20e6,  9000000, 0.75));

    447. 

  447.  //   addTransmissionMode (new FecQamMode  (20e6, 12000000, 0.5,   4));

    448. 

  448.   //  addTransmissionMode (new FecQamMode  (20e6, 18000000, 0.75,  4));

    449. 

  449.    // addTransmissionMode (new FecQamMode  (20e6, 24000000, 0.5,   16));

    450. 

  450.    // addTransmissionMode (new FecQamMode  (20e6, 36000000, 0.75,  16));

    451. 

  451.    // addTransmissionMode (new FecQamMode  (20e6, 48000000, 0.666, 64));

    452. 

  452.    // addTransmissionMode (new FecQamMode  (20e6, 54000000, 0.75,  64));

    453. 

  453. }
    454.