上行PRACH同步過程.doc

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(wǎng)格側(cè)的目標(biāo)小區(qū)進行初始通信的第一條消息內(nèi)容,其主要作用就是獲取目標(biāo)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(chǎn)生嚴(yán)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(chǎn)生的呢,協(xié)議定義了兩種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(guān)性和互相關(guān)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(guān).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)覆蓋距離(km)01038001001ms1416848005202ms77220316002002ms29368416007203ms1004151339157us1.4Preamble format的格式與小區(qū)半徑的關(guān)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(dāng)PRACH格式為03時，根序列為0837，其838個，分為32個大的邏輯組，每個邏輯索引唯一對應(yīng)一個物理序列；當(dāng)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(yīng)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, 210, 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, 796, 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, 145, 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, 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, 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, 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, 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, 662, 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, 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, 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, 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, 467, 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, 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, 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) Format4 (36.211 table5.7.2-5)0 191138213731364135513461337132813191301012920 391112812127131261412515124161231712218121191202011940 592111822117231162411525114261132711228111291103010960 79311083210733106341053510436103371023810139100409980 994198429743964495459446934792489149905089100 1195188528753865485558456835782588159806079120 137617862776376647565746673677268716970-PRACH的根序列產(chǎn)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(zhuǎn)一圈,都能得到一條序列,這樣一條序列就叫一個Preamble,那總共838個根序列,每個根序列上有839個點,故每條根序列能產(chǎn)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?jīng)Q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(chǎn)生=int(839/9)=9，即一條根序列可產(chǎn)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(xì)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UE與網(wǎng)絡(luò)側(cè)的隨機接入同步過程.一組是網(wǎng)絡(luò)側(cè)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 messageSizeGroupA,有些廠家將此參數(shù)寫為(raSmallVolUl)1.1.4 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(guān).參數(shù)PRACHConfig是指PRACH的format格式,其中包含了一個無線幀內(nèi)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)03522040113623050123724060203825070213926080224030.5090304130.51100314230.5211032433101204044311130414532014042463301505047340160514840.50170524940.51180605040.5219061514102010.50524112110.51534202210.52544302311055440241115645025120574602613058N/AN/AN/A2714059N/AN/AN/A2815060N/AN/AN/A2916061N/AN/AN/A3020.5062N/AN/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)(0,1,0,0)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)(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)(0,0,1,1)(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)(0,0,0,0)(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)(0,0,0,2)(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)(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)(1,0,0,0)(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)(0,0,0,0)(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)(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)(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)(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)(0,0,0,0)(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)(1,0,0,0)(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/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/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,*)(0,0,0,*)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,*)(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,*)(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,*)(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,*)(2,0,0,*)(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PRAC