上行PRACH同步过程.docx

1.1.1 1.1上行RACK道知识上行RACH言道作用1.1.2 上行PRACH言道(PhysicalRandomAccesschannel)上行随机接入信道，用于UE与网格侧的目标小区进行初始通信的第一条消息内容，其主要作用就是获取目标小区的上行同步^上行RACH言道资源preamble原理要取得与UE的上行同步，就要在PRACH言道上进行上行同步，然而上行同步是通过发送上行同步码来获得的.每个小区都有64个上行同步码，在相同的频率情况下，如果两个小区的上行同步码相同，就会产生严重的上行同步干扰，就无法成功获得上行同步.那Preamble码是由什么产生的呢，协议定义了两种ZC序列(长度分别为839bit和139bit)，前面讲PSS的ZC序列的特性时，ZC序列具有很好的自相关性和互相关性.任意两条ZC序列都是相互正交无干扰的.格式)为0~3,preamble这两种ZC序列的长度为839bit时，其preambleformat(PreamblePreambleformat(table5.7.2-1)Nzc指preamble的长度03839,序列个数水度-1=838个4139,序列个数水度-1=138个format与小区覆盖半径有关CEUl-RANGEK*KXX103Fc*rmOFOfTTlMt1—nKmFomicit2TDOonly.pRTSPreambleformattC(P)Tpreamble-sequence(us)TGT(us)总时土侦小区覆盖距离(km)01038001001ms1416848005202ms77220316002002ms29368416007203ms1004151339157us1.4Preambleformat的格式与小区半径的关系如下：以format0以例:小区半径=min(GT,CP}*光速/2=min(103us,100us)*光速/2=100*10人(-6)*3*10人8/2=150000=15km参数ra-PreambleIndex/root-SequenceIndex:preamble的rootsequenceindex索弓I编号，当PRAC略式为0〜3时，根序列为0〜837,其838个，分为32个大的逻辑组，每个逻辑索引唯一对应一个物理序列；当PRAC隔式为4时，根序列为0〜137,其138个，分为7个逻辑组,每个逻辑索引也是唯一对应一个物理序列；由小区配置可用的preamblesequence-index编号,在SIB中广播，一般小区每隔8使用一个根序列（rootsequence重新排序得到逻辑号，考虑preamble的峰均比），排序规律：每两个每对相加=839.Preamble逻辑根序列号索引Preamble物理根序列号索引u（按逻辑根序列号升序排列）Format0〜3（36.211table5.7.2-4）023129,710,140,699,120,719,210,629,168,671,84,755,105,734,93,746,70,769,60,779,2,837,1,83824/956,783,112,727,148,691303580,759,42,797,40,799364135,804,73,766,146,693425131,808,28,811,30,809,27,812,29,81052书324,815,48,791,68,771,74,765,178,661,136,703647586,753,78,761,43,796,39,800,20,819,21,818768995,744,202,637,190,649,181,658,137,702,125,714,151,68890115217,622,128,711,142,697,122,717,203,636,118,721,110,729,89,750,103,736,61,778,55,784,15,824,14,825116T3512,827,23,816,34,805,37,802,46,793,207,632,179,660,145,694,130,709,223,616136F67228,611,227,612,132,707,133,706,143,696,135,704,161,678,201,638,173,666,106,733,83,756,91,748,66,773,53,786,10,829,9,830168t2037,832,8,831,16,823,47,792,64,775,57,782,104,735,101,738,108,731,208,631,184,655,197,642,191,648,121,718,141,698,149,690,216,623,218,621204：263152,687,144,695,134,705,138,701,199,640,162,677,176,663,119,720,158,681,164,675,174,665,171,668,170,669,87,752,169,670,88,751,107,732,81,758,82,757,100,739,98,741,71,768,59,780,65,774,50,789,49,790,26,813,17,822,13,826,6,833264€275,834,33,806,51,788,75,764,99,740,96,743,97,742,166,673,172,667,175,664,187,652,163,676,185,654,200,639,114,725,189,650,115,724,194,645,195,644,192,647,182,657,157,682,156,683,211,628,154,685,123,716,139,700,212,627,153,686,213,626,215,624,150,689328€83225,614,224,615,221,618,220,619,127,712,147,692,124,715,193,646,205,634,206,633,116,723,160,679,186,653,167,672,79,760,85,754,77,762,92,747,58,781,62,777,69,770,54,785,36,803,32,807,25,814,18,821,11,828,4,835384N553,836,19,820,22,817,41,798,38,801,44,795,52,787,45,794,63,776,67,772,72767,76,763,94,745,102,737,90,749,109,730,165,674,111,728,209,630,204,635,117,722,188,651,159,680,198,641,113,726,183,656,180,659,177,662,196,643,155,684,214,625,126,713,131,708,219,620,222,617,226,613456书13230,609,232,607,262,577,252,587,418,421,416,423,413,426,411,428,376,463,395,444,283,556,285,554,379,460,390,449,363,476,384,455,388,451,386,453,361,478,387,452,360,479,310,529,354,485,328,511,315,524,337,502,349,490,335,504,324,515514W61323,516,320,519,334,505,359,480,295,544,385,454,292,547,291,548,381,458,399,440,380,459,397,442,369,470,377,462,410,429,407,432,281,558,414,425,247,592,277,562,271,568,272,567,264,575,259,580562书29237,602,239,600,244,595,243,596,275,564,278,561,250,589,246,593,417,422,248,591,394,445,393,446,370,469,365,474,300,539,299,540,364,475,362,477,298,541,312,527,313,526,314,525,353,486,352,487,343,496,327,512,350,489,326,513,319,520,332,507,333,506,348,491,347,492,322,517630治59330,509,338,501,341,498,340,499,342,497,301,538,366,473,401,438,371,468,408,431,375,464,249,590,269,570,238,601,234,605660刀07257,582,273,566,255,584,254,585,245,594,251,588,412,427,372,467,282,557,403,436,396,443,392,447,391,448,382,457,389,450,294,545,297,542,311,528,344,495,345,494,318,521,331,508,325,514,321,518708刀29346,493,339,500,351,488,306,533,289,550,400,439,378,461,374,465,415,424,270,569,241,598730751231,608,260,579,268,571,276,563,409,430,398,441,290,549,304,535,308,531,358,481,316,523752"765293,546,288,551,284,555,368,471,253,586,256,583,263,576766刀77242,597,274,565,402,437,383,456,357,482,329,510778789317,522,307,532,286,553,287,552,266,573,261,578790795236,603,303,536,356,483796书03355,484,405,434,404,435,406,433804七09235,604,267,572,302,537810七15309,530,265,574,233,606816七19367,472,296,543820E7336,503,305,534,373,466,280,559,279,560,419,420,240,599,258,581,229,610Preamble逻辑根序列号索引Preambled理根序列号索引u(按逻辑根序列号升序排列)Format4(36.211t。