上行PRACH同步過程

1、1.1 上行RACH信道知識1.1.1 上行RACH信道作用上行PRACH信道(Physical Random Access channel)上行隨機接入信道,用于UE與網格側的目標小區(qū)進行初始通信的第一條消息內容,其主要作用就是獲取目標小區(qū)的上行同步.1.1.2 上行RACH信道資源preamble原理手機要取得與UE的上行同步,手機就要在PRACH信道上進行上行同步,然而上行同步是手機通過發(fā)送上行同步碼來獲得的.每個小區(qū)都有64個上行同步碼,在相同的頻率情況下,如果兩個小區(qū)的上行同步碼相同,就會產生嚴重的上行同步干擾,就無法成功獲得上行同步.那Preamble碼是由什么產生的呢,協(xié)議定義了

2、兩種ZC序列(長度分別為839bit和139bit),前面講PSS的ZC序列的特性時,ZC序列具有很好的自相關性和互相關性.任意兩條ZC序列都是相互正交無干擾的.這兩種ZC序列的長度為839bit時,其preamble format(Preamble格式)為03, preamble format與小區(qū)覆蓋半徑有關.Preamble format (table 5.7.2-1)指preamble的長度0 3839，序列個數(shù)=長度-1=838個4139，序列個數(shù)=長度-1=138個Preamble formatTCP(us)Tpreamble-sequence(us)TGT(us)總時長小區(qū)覆蓋距

3、離(km)01038001001ms1416848005202ms77220316002002ms29368416007203ms1004151339157us1.4Preamble format的格式與小區(qū)半徑的關系如下:以format0以例:小區(qū)半徑=min(GT,CP*光速/2=min(103us,100us)*光速/2=100*10(-6)*3*108/2=150000=15km參數(shù)ra-PreambleIndex/root-SequenceIndex:preamble的root sequence index索引編號，當PRACH格式為03時，根序列為0837，其838個，分為32個大

4、的邏輯組，每個邏輯索引唯一對應一個物理序列；當PRACH格式為4時，根序列為0137，其138個，分為7個邏輯組, 每個邏輯索引也是唯一對應一個物理序列；由小區(qū)配置可用的preamble sequence-index編號，在SIB中廣播，一般小區(qū)每隔8使用一個根序列（rootsequence重新排序得到邏輯號，考慮preamble的峰均比）, 排序規(guī)律：每兩個每對相加=839.Preamble邏輯根序列號索引Preamble物理根序列號索引 (按邏輯根序列號升序排列)Format03 (36.211 table5.7.2-4)023129, 710, 140, 699, 120, 719, 2

5、10, 629, 168, 671, 84, 755, 105, 734, 93, 746, 70, 769, 60, 779,2, 837, 1, 838242956, 783, 112, 727, 148, 691303580, 759, 42, 797, 40, 799364135, 804, 73, 766, 146, 693425131, 808, 28, 811, 30, 809, 27, 812, 29, 810526324, 815, 48, 791, 68, 771, 74, 765, 178, 661, 136, 703647586, 753, 78, 761, 43, 7

6、96, 39, 800, 20, 819, 21, 818768995, 744, 202, 637, 190, 649, 181, 658, 137, 702, 125, 714, 151, 68890115217, 622, 128, 711, 142, 697, 122, 717, 203, 636, 118, 721, 110, 729, 89, 750, 103, 736, 61, 778, 55, 784, 15, 824, 14, 82511613512, 827, 23, 816, 34, 805, 37, 802, 46, 793, 207, 632, 179, 660, 1

7、45, 694, 130, 709, 223, 616136167228, 611, 227, 612, 132, 707, 133, 706, 143, 696, 135, 704, 161, 678, 201, 638, 173, 666, 106, 733, 83, 756, 91, 748, 66, 773, 53, 786, 10, 829, 9, 8301682037, 832, 8, 831, 16, 823, 47, 792, 64, 775, 57, 782, 104, 735, 101, 738, 108, 731, 208, 631, 184, 655, 197, 642

8、, 191, 648, 121, 718, 141, 698, 149, 690, 216, 623, 218, 621204263152, 687, 144, 695, 134, 705, 138, 701, 199, 640, 162, 677, 176, 663, 119, 720, 158, 681, 164, 675, 174, 665, 171, 668, 170, 669, 87, 752, 169, 670, 88, 751, 107, 732, 81, 758, 82, 757, 100, 739, 98, 741, 71, 768, 59, 780, 65, 774, 50

9、, 789, 49, 790, 26, 813, 17, 822, 13, 826, 6, 8332643275, 834, 33, 806, 51, 788, 75, 764, 99, 740, 96, 743, 97, 742, 166, 673, 172, 667, 175, 664, 187, 652, 163, 676, 185, 654, 200, 639, 114, 725, 189, 650, 115, 724, 194, 645, 195, 644, 192, 647, 182, 657, 157, 682, 156, 683, 211, 628, 154, 685, 123

10、, 716, 139, 700, 212, 627, 153, 686, 213, 626, 215, 624, 150, 689328383225, 614, 224, 615, 221, 618, 220, 619, 127, 712, 147, 692, 124, 715, 193, 646, 205, 634, 206, 633, 116, 723, 160, 679, 186, 653, 167, 672, 79, 760, 85, 754, 77, 762, 92, 747, 58, 781, 62, 777, 69, 770, 54, 785, 36, 803, 32, 807,

11、 25, 814, 18, 821, 11, 828, 4, 8353844553, 836, 19, 820, 22, 817, 41, 798, 38, 801, 44, 795, 52, 787, 45, 794, 63, 776, 67, 772, 72767, 76, 763, 94, 745, 102, 737, 90, 749, 109, 730, 165, 674, 111, 728, 209, 630, 204, 635, 117, 722, 188, 651, 159, 680, 198, 641, 113, 726, 183, 656, 180, 659, 177, 66

12、2, 196, 643, 155, 684, 214, 625, 126, 713, 131, 708, 219, 620, 222, 617, 226, 613456513230, 609, 232, 607, 262, 577, 252, 587, 418, 421, 416, 423, 413, 426, 411, 428, 376, 463, 395, 444, 283, 556, 285, 554, 379, 460, 390, 449, 363, 476, 384, 455, 388, 451, 386, 453, 361, 478, 387, 452, 360, 479, 310

13、, 529, 354, 485, 328, 511, 315, 524, 337, 502, 349, 490, 335, 504, 324, 515514561323, 516, 320, 519, 334, 505, 359, 480, 295, 544, 385, 454, 292, 547, 291, 548, 381, 458, 399, 440, 380, 459, 397, 442, 369, 470, 377, 462, 410, 429, 407, 432, 281, 558, 414, 425, 247, 592, 277, 562, 271, 568, 272, 567,

14、 264, 575, 259, 580562629237, 602, 239, 600, 244, 595, 243, 596, 275, 564, 278, 561, 250, 589, 246, 593, 417, 422, 248, 591, 394, 445, 393, 446, 370, 469, 365, 474, 300, 539, 299, 540, 364, 475, 362, 477, 298, 541, 312, 527, 313, 526, 314, 525, 353, 486, 352, 487, 343, 496, 327, 512, 350, 489, 326,

15、513, 319, 520, 332, 507, 333, 506, 348, 491, 347, 492, 322, 517630659330, 509, 338, 501, 341, 498, 340, 499, 342, 497, 301, 538, 366, 473, 401, 438, 371, 468, 408, 431, 375, 464, 249, 590, 269, 570, 238, 601, 234, 605660707257, 582, 273, 566, 255, 584, 254, 585, 245, 594, 251, 588, 412, 427, 372, 46

16、7, 282, 557, 403, 436, 396, 443, 392, 447, 391, 448, 382, 457, 389, 450, 294, 545, 297, 542, 311, 528, 344, 495, 345, 494, 318, 521, 331, 508, 325, 514, 321, 518708729346, 493, 339, 500, 351, 488, 306, 533, 289, 550, 400, 439, 378, 461, 374, 465, 415, 424, 270, 569, 241, 598730751231, 608, 260, 579,

17、 268, 571, 276, 563, 409, 430, 398, 441, 290, 549, 304, 535, 308, 531, 358, 481, 316, 523752765293, 546, 288, 551, 284, 555, 368, 471, 253, 586, 256, 583, 263, 576766777242, 597, 274, 565, 402, 437, 383, 456, 357, 482, 329, 510778789317, 522, 307, 532, 286, 553, 287, 552, 266, 573, 261, 578790795236

18、, 603, 303, 536, 356, 483796803355, 484, 405, 434, 404, 435, 406, 433804809235, 604, 267, 572, 302, 537810815309, 530, 265, 574, 233, 606816819367, 472, 296, 543820837336, 503, 305, 534, 373, 466, 280, 559, 279, 560, 419, 420, 240, 599, 258, 581, 229, 610Preamble邏輯根序列號索引Preamble物理根序列號索引 (按邏輯根序列號升序排列

19、) Format4 (36.211 table5.7.2-5)0 191138213731364135513461337132813191301012920 391112812127131261412515124161231712218121191202011940 592111822117231162411525114261132711228111291103010960 79311083210733106341053510436103371023810139100409980 994198429743964495459446934792489149905089100 11951885287

20、53865485558456835782588159806079120 137617862776376647565746673677268716970-PRACH的根序列產生公式：是根ZC序列的長度,u為第u個根序列編號，然后通過循環(huán)移位這兩種ZC序列,長度分別為839bit和139bit.這兩種序列協(xié)議把它稱為根序列RootSequence,以839bit的序列為例,這種序列的個數(shù)=長度-1=838個.這838個序列中任意兩個根序列都是相互正交和無干擾的.拿其中任何一個序列,由于序列上有839個點,選擇任意一個點作為起點逆時針轉一圈,都能得到一條序列,這樣一條序列就叫一個Preamble,那

21、總共838個根序列,每個根序列上有839個點,故每條根序列能產生839條Preamble,則總共的Preamble總數(shù)=838*839=703082條Preamble.任意兩條Preamble都是相互正交和無干擾的. 參數(shù):也是與小區(qū)覆蓋半徑決定的,比如小區(qū)覆蓋半徑為14公里時,Ncs索引取值一般可以是11(12.52KM)或10(10.09KM),它是Preamble的Cyclic shift，目前只支持非限制集，限制集只適用于高速場景。若取值為11，則表示在此圓上每隔93個點取一個,每兩個循環(huán)移位間隔為93,由于長度為839，因此這條根序列能產生=int(839/9)=9，即一條根序列可產

22、生9個preamble，因此需要ubound(64/9)=8個根序列，因此規(guī)劃時每小區(qū)的root-sequence差8，=11。的大小決定小區(qū)半徑，例取11，則小區(qū)半徑=93*preamble時長/preamble長度/2=800us*間隔93*C光速/839/2=13.3km，其中800us*間隔93就是指間隔的時延。 NCS 配置(preamble format4見36.211 table5.7.2-3)NCS值021426384105126151.1.3 上行RACH信道資源preamble種類個數(shù)及劃分細則 每個小區(qū)都有64(編號為063)個Preamble碼,協(xié)議把它劃分為2組,用于

23、UE與網絡側的隨機接入同步過程.一組是網絡側eNB指定分配給UE的preamble碼,這種稱為專用或非競爭的,這個碼其它用戶不能使用;另一組是UE自已隨機選的,大家都可以用,這種稱為競爭性的隨機接入碼.有參數(shù)指定隨機接入碼的個數(shù)numberOfRA-Preambles,此參數(shù)在SIB2中下發(fā).如果此參數(shù)為48個(編號為047),則剩下的就是專用的Preamble碼(4863).同時協(xié)議又將競爭的分為GroupA和GroupB兩組.具體如下圖: 如果是競爭性的Preamble,那到底選用GroupA還是GroupB呢?在此需要提醒一下,假如eNB在隨機接入用戶同時很多的時候,eNB對GroupB

24、比GroupA的優(yōu)先級要高點.因此eNB選擇GroupB時,需滿足兩個條件:1).UE的信號要好,這樣才能保證優(yōu)先處理時的可靠性更高(鏈路損耗要小些)pathloss<pathlossThreshold pathlossThreshold=Pmax- preambleInitialReceivedTargetPower deltaPreMsg3messagePowerOffsetGroupB 2).手機中有較大的上行數(shù)據(jù)塊要發(fā)送(preamble中需要承載的消息量+MAC header大小)> messageSizeGroupA,有些廠家將此參數(shù)寫為(raSmallVolUl)1.

25、1.4 上行RACH信道資源preamble頻域位置 前面講過,PRACH資源占頻域的上行6個PRB,fomat03格式的Preamble的長度為839bit, 每個子載波的帶寬為1.25KHZ, 則占用頻域帶寬為=7.5KHZ*839=1.048M,占用連續(xù)6個PRB(1.08M)的帶寬;長度為139bit的Preamble的子載波的帶寬為7.5JHZ,則同樣占用7.5KHZ*139=1.0425M(連續(xù)6個PRB)的帶寬. 在20MHZ的帶寬下,上行總共有100個PRB,那PRACH到底在哪幾個PRB呢.這與PRACHConfigIndex和上下行子幀配置有關.參數(shù)PRACHConfig是

26、指PRACH的format格式,其中包含了一個無線幀內PRACH信道的個數(shù)(稱為PRACH密度Density,1代表每無線幀出現(xiàn)一次,0.5代表第2個無線幀出現(xiàn)一次,其它按此類推).PRACHconfigurationIndexPreambleFormatDensity(Per10 msDRA)VersionVRAPRACHconfigurationIndexPreambleFormatDensity(Per10 msDRA)VersionVRA000.503220.52100.5133210200.52342113（目前配置）01(preamble時長1ms)0352204011362305

27、0123724060203825070213926080224030.5090304130.51100314230.5211032433101204044311130414532014042463301505047340160514840.50170524940.51180605040.5219061514102010.50524112110.51534202210.52544302311055440241115645025120574602613058N/AN/AN/A2714059N/AN/AN/A2815060N/AN/AN/A2916061N/AN/AN/A3020.5062N/AN/

28、AN/A3120.5163N/AN/AN/APRACH configuration Index (See Table 5.7.1-3)TDD PRACH的時間的頻域位置UL/DL configuration (See Table 4.2-2)01234560(0,1,0,2)(0,1,0,1)(0,1,0,0)(0,1,0,2)(0,1,0,1)(0,1,0,0)(0,1,0,2)1(0,2,0,2)(0,2,0,1)(0,2,0,0)(0,2,0,2)(0,2,0,1)(0,2,0,0)(0,2,0,2)2(0,1,1,2)(0,1,1,1)(0,1,1,0)(0,1,0,1)(0,1,0,

29、0)N/A(0,1,1,1)3(0,0,0,2)(0,0,0,1)(0,0,0,0)(0,0,0,2)(0,0,0,1)(0,0,0,0)(0,0,0,2)4(0,0,1,2)(0,0,1,1)(0,0,1,0)(0,0,0,1)(0,0,0,0)N/A(0,0,1,1)5(0,0,0,1)(0,0,0,0)N/A(0,0,0,0)N/AN/A(0,0,0,1)6(0,0,0,2)(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,0,0)(0,0,0,0)(0,0,0,2)(0,0,1,2)(0,0,1,1)(0,0,1,0)(0,0,0,2)(0,0,0,1)(1,0,0,0)

30、(0,0,1,1)7(0,0,0,1)(0,0,0,0)N/A(0,0,0,0)N/AN/A(0,0,0,1)(0,0,1,1)(0,0,1,0)(0,0,0,2)(0,0,1,0)8(0,0,0,0)N/AN/A(0,0,0,0)N/AN/A(0,0,0,0)(0,0,1,0)(0,0,0,1)(0,0,1,1)9(0,0,0,1)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,1)(0,0,0,2)(0,0,0,1)(0,0,1,0)(0,0,0,1)(0,0,0,1)(1,0,0,0)(0,0,0,2)(0,0,1,2)(0,0,1

31、,1)(1,0,0,0)(0,0,0,2)(1,0,0,1)(2,0,0,0)(0,0,1,1)10 (0,0,0,0)(0,0,0,1)(0,0,0,0)N/A(0,0,0,0)N/A (0,0,0,0)(0,0,1,0) (0,0,1,0)(0,0,1,0)(0,0,0,1)(0,0,0,2)(0,0,1,1)(0,0,1,1)(1,0,1,0)(1,0,0,0)(0,0,1,0)11N/A(0,0,0,0)N/AN/AN/AN/A (0,0,0,1)(0,0,0,1)(0,0,1,0)(0,0,1,0)(0,0,1,1)12(0,0,0,1)(0,0,0,0)(0,0,0,0)(0,0,

32、0,0)(0,0,0,0)(0,0,0,0)(0,0,0,1)(0,0,0,2)(0,0,0,1)(0,0,1,0)(0,0,0,1)(0,0,0,1)(1,0,0,0)(0,0,0,2)(0,0,1,1)(0,0,1,0)(1,0,0,0)(0,0,0,2)(1,0,0,0)(2,0,0,0)(0,0,1,0)(0,0,1,2)(0,0,1,1)(1,0,1,0)(1,0,0,2)(1,0,0,1)(3,0,0,0)(0,0,1,1)13(0,0,0,0)N/AN/A(0,0,0,0)N/AN/A(0,0,0,0)(0,0,0,2)(0,0,0,1)(0,0,0,1)(0,0,1,0)(0,

33、0,0,2)(0,0,0,2)(0,0,1,2)(1,0,0,1)(0,0,1,1)14(0,0,0,0)N/AN/A(0,0,0,0)N/AN/A(0,0,0,0)(0,0,0,1)(0,0,0,1)(0,0,0,2)(0,0,1,0)(0,0,0,2)(0,0,1,0)(0,0,1,1)(1,0,0,0)(0,0,1,1)15(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,1)(0,0,0,1)(0,0,1,0)(0,0,0,1)(0,0,0,1)(1,0,0,0)(0,0,0,1)(0,0,0,2

34、)(0,0,1,0)(1,0,0,0)(0,0,0,2)(1,0,0,0)(2,0,0,0)(0,0,0,2)(0,0,1,1)(0,0,1,1)(1,0,1,0)(1,0,0,1)(1,0,0,1)(3,0,0,0)(0,0,1,0)(0,0,1,2)(1,0,0,1)(2,0,0,0)(1,0,0,2)(2,0,0,1)(4,0,0,0)(0,0,1,1)16(0,0,0,1)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,0)N/AN/A(0,0,0,2)(0,0,0,1)(0,0,1,0)(0,0,0,1)(0,0,0,1)(0,0,1,0)(0,0,1,0)(1,

35、0,0,0)(0,0,0,2)(1,0,0,0)(0,0,1,1)(0,0,1,1)(1,0,1,0)(1,0,0,0)(1,0,0,1)(0,0,1,2)(1,0,1,1)(2,0,1,0)(1,0,0,2)(2,0,0,0)17(0,0,0,0)(0,0,0,0)N/A(0,0,0,0)N/AN/AN/A(0,0,0,1)(0,0,0,1)(0,0,0,1)(0,0,0,2)(0,0,1,0)(0,0,0,2)(0,0,1,0)(0,0,1,1) (1,0,0,0)(0,0,1,2)(1,0,0,0)(1,0,0,1)18(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,

36、0)(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,0,1)(0,0,0,1)(0,0,1,0)(0,0,0,1)(0,0,0,1)(1,0,0,0)(0,0,0,1)(0,0,0,2)(0,0,1,0)(1,0,0,0)(0,0,0,2)(1,0,0,0)(2,0,0,0)(0,0,0,2)(0,0,1,0)(0,0,1,1)(1,0,1,0)(1,0,0,0)(1,0,0,1)(3,0,0,0)(0,0,1,0)(0,0,1,1)(1,0,0,1)(2,0,0,0)(1,0,0,1)(2,0,0,0)(4,0,0,0)(0,0,1,1)(0,0,1,2)(1,0,1,1)(

37、2,0,1,0)(1,0,0,2)(2,0,0,1)(5,0,0,0)(1,0,0,2)19N/A(0,0,0,0)N/AN/AN/AN/A(0,0,0,0)(0,0,0,1)(0,0,0,1)(0,0,1,0)(0,0,0,2)(0,0,1,1)(0,0,1,0)(1,0,0,0)(0,0,1,1)(1,0,1,0)(1,0,1,1)20 / 30(0,1,0,1)(0,1,0,0)N/A(0,1,0,1)(0,1,0,0)N/A(0,1,0,1)21 / 31(0,2,0,1)(0,2,0,0)N/A(0,2,0,1)(0,2,0,0)N/A(0,2,0,1)22 / 32(0,1,1,1

38、)(0,1,1,0)N/AN/AN/AN/A(0,1,1,0)23 / 33(0,0,0,1)(0,0,0,0)N/A(0,0,0,1)(0,0,0,0)N/A(0,0,0,1)24 / 34(0,0,1,1)(0,0,1,0)N/AN/AN/AN/A(0,0,1,0)25 / 35(0,0,0,1)(0,0,0,0)N/A(0,0,0,1)(0,0,0,0)N/A(0,0,0,1)(0,0,1,1)(0,0,1,0)(1,0,0,1)(1,0,0,0)(0,0,1,0)26 / 36(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,1,1)(

39、0,0,1,0)N/A(1,0,0,1)(1,0,0,0)N/A(0,0,1,0)(1,0,0,1)(1,0,0,0)(2,0,0,1)(2,0,0,0)(1,0,0,1)27 / 37(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,1,1)(0,0,1,0)N/A(1,0,0,1)(1,0,0,0)N/A(0,0,1,0)(1,0,0,1)(1,0,0,0)(2,0,0,1)(2,0,0,0)(1,0,0,1)(1,0,1,1)(1,0,1,0)(3,0,0,1)(3,0,0,0)(1,0,1,0)28 / 38(0,0,0,1)(0,0,

40、0,0)(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,1,1)(0,0,1,0)(1,0,0,1)(1,0,0,0)(0,0,1,0)(1,0,0,1)(1,0,0,0)N/A(2,0,0,1)(2,0,0,0)N/A(1,0,0,1)(1,0,1,1)(1,0,1,0)(3,0,0,1)(3,0,0,0)(1,0,1,0)(2,0,0,1)(2,0,0,0)(4,0,0,1)(4,0,0,0)(2,0,0,1)29 /39(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,0,0)(0,0,0,1)(0,0,1,1)(0,0,1,0)(1,0,0,1)(1,0,

41、0,0)(0,0,1,0)(1,0,0,1)(1,0,0,0)N/A(2,0,0,1)(2,0,0,0)N/A(1,0,0,1)(1,0,1,1)(1,0,1,0)(3,0,0,1)(3,0,0,0)(1,0,1,0)(2,0,0,1)(2,0,0,0)(4,0,0,1)(4,0,0,0)(2,0,0,1)(2,0,1,1)(2,0,1,0)(5,0,0,1)(5,0,0,0)(2,0,1,0)40(0,1,0,0)N/AN/A(0,1,0,0)N/AN/A(0,1,0,0)41(0,2,0,0)N/AN/A(0,2,0,0)N/AN/A(0,2,0,0)42(0,1,1,0)N/AN/AN/

42、AN/AN/AN/A43(0,0,0,0)N/AN/A(0,0,0,0)N/AN/A(0,0,0,0)44(0,0,1,0)N/AN/AN/AN/AN/AN/A45(0,0,0,0)N/AN/A(0,0,0,0)N/AN/A(0,0,0,0)(0,0,1,0)(1,0,0,0)(1,0,0,0)46(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,1,0)N/AN/A(1,0,0,0)N/AN/A(1,0,0,0)(1,0,0,0)(2,0,0,0)(2,0,0,0)47(0,0,0,0)(0,0,0,0)(0,0,0,0)(0,0,1,0)N/AN/A(1,0,0,0)N/AN

43、/A(1,0,0,0)(1,0,0,0)(2,0,0,0)(2,0,0,0)(1,0,1,0)(3,0,0,0)(3,0,0,0)48(0,1,0,*)(0,1,0,*)(0,1,0,*)(0,1,0,*)(0,1,0,*)(0,1,0,*)(0,1,0,*)49(0,2,0,*)(0,2,0,*)(0,2,0,*)(0,2,0,*)(0,2,0,*)(0,2,0,*)(0,2,0,*)50(0,1,1,*)(0,1,1,*)(0,1,1,*)N/AN/AN/A(0,1,1,*)51(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0

44、,0,0,*)52(0,0,1,*)(0,0,1,*)(0,0,1,*)N/AN/AN/A(0,0,1,*)53(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,1,*)(0,0,1,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(0,0,1,*)54(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,1,*)(0,0,1,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*

45、)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(2,0,0,*)(2,0,0,*)(2,0,0,*)(1,0,0,*)55(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,1,*)(0,0,1,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(2,0,0,*)(2,0,0,*)(2,0,0,*)(1,0,0,*)(1,0,1,*)(1,0,1,*)(1,0,1,*)(3,0,0,*)

46、(3,0,0,*)(3,0,0,*)(1,0,1,*)56(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,1,*)(0,0,1,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(2,0,0,*)(2,0,0,*)(2,0,0,*)(1,0,0,*)(1,0,1,*)(1,0,1,*)(1,0,1,*)(3,0,0,*)(3,0,0,*)(3,0,0,*)(1,0,1,*)(2,0,0,*)(2,0,0,*)(

47、2,0,0,*)(4,0,0,*)(4,0,0,*)(4,0,0,*)(2,0,0,*)57(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,0,*)(0,0,1,*)(0,0,1,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(0,0,1,*)(1,0,0,*)(1,0,0,*)(1,0,0,*)(2,0,0,*)(2,0,0,*)(2,0,0,*)(1,0,0,*)(1,0,1,*)(1,0,1,*)(1,0,1,*)(3,0,0,*)(3,0,0,*)(3,0,0,*)(1,0,1,*)(2

48、,0,0,*)(2,0,0,*)(2,0,0,*)(4,0,0,*)(4,0,0,*)(4,0,0,*)(2,0,0,*)(2,0,1,*)(2,0,1,*)(2,0,1,*)(5,0,0,*)(5,0,0,*)(5,0,0,*)(2,0,1,*)58N/AN/AN/AN/AN/AN/AN/A59N/AN/AN/AN/AN/AN/AN/A60N/AN/AN/AN/AN/AN/AN/A61N/AN/AN/AN/AN/AN/AN/A62N/AN/AN/AN/AN/AN/AN/A63N/AN/AN/AN/AN/AN/AN/A以PRACHconfigIndex=3和上下行子幀配置=2(1:3)為例,其

49、交集為(0,0,0,0).組合中(0,0,0,0),第一個0就是指PRACH的頻域的位置的值,在此組合中為0, .其頻域真正位置為.由于=0,因此=參數(shù)就是指PRACH信道離帶寬兩端邊界的PRB編號0或100的偏離位置,如果PRACH在帶寬底端,且要占用6個PRB,則=5(PRAB編號05,共6個PRB是PRACH信;) ;如果PRACH在帶寬頂端,且要占用6個PRB,則=94(PRAB編號9499,共6個PRB是PRACH信道).因為考慮到上行SC-FDMA的特性,上行PUSCH必須要參夠連續(xù)且可以過到最大的峰值速率,因此協(xié)議規(guī)定PRACH只能位于帶寬的兩端.1.1.5 上行RACH信道資源preamble時域位置前面講PRACH頻域位置時講過,PRACH的頻域位置與PRACHconigIndex/上下行子幀配置/參數(shù)這3個因素決定. 同樣以PRACHConfigIndex=3且上行下子幀配置為2時,還是組合(0,0,0,0),那這個組合不僅決定了PRACH的PRACH的頻域位置,也同樣決定PRACH的時域位置.具體是此組合的后面3個值決定了PRACH的時域位置.對應組合(0,0,0,0)中第2個0是