小区搜索.docx
小区搜索小区搜索是为了获得网络的时频同步的过程，并获得小区的PCIoUE接收PSSSSS信号来执行小区搜索，UE假设物理广播信道（PBCH）、PSS和SSS的接收时机是在连续符号中的，并且形成SS/PBCH块。UE假设SSS、PBCHDM-RS和PBeH数据具有相同的EPREoUE可以假设SS/PBCH块中PSS-EPRE与SSS-EPRE的比率为Odb或3db。如果没有向UE提供专用的更高层参数，则UE可以假设当UE用si-rntip-rnti或ra-rnti加扰的crc监视dci格式i_o的pdcch时，pdcchDMRSEPRE与SSSEPRE的比率在-8db和8db之内。在SSB块的半帧中，候选SS/PBCH块的第一个符号索引根据SS/PBCH块的SCS确定，其中索引0对应于半帧中的第一时隙的第一符号。<StartSymbolsforeachsubcarrierspacingandfrequency>SubcarrierSpacingOFDMSymbol(s)f<=3Ghz3Ghz<f<=6Ghz6Ghz<fCaseA:2,8+14nn二0,10,1,2,315KHzS二2,8,16,22(Lmax二OS=2,8,16,22,30,36,44,50(Lmax-8)(4,8,16,20+28nn二0n=0,1CaseB:30KhzS二4,8,16,20(Lmax二4)S=4,8,16,20,32,36,44,48(Lmax-8)2,8+14nn二0,1=0,1,2,3CaseC:30KhzS二2,8,16,22(Lmax-I)S二2,8,16,22,30,36,44,50(Lmax-8)CaseD:120(4,8,16,20+28nn=0,1,2,3,5,6,7,8,10,11,12,13,15,16,17,18Khzs=4,8,16,20,32,36,44,48,60,64,72,76,88,92,100,104,144,148,156,160,172,176,184,188,200,204,212,216,228,232,240,244,284,288,296,300,312,316,324,328,340,344,352,356,368,372,380,384,424,428,436,440,452,456,464,468,480,484,492,496,508,512,520,524(Lmax-64)CaseE:8,12,16,20,32,n=0,1,2,3,5,6,7,8240Khz36,40,44+56ns8,12,16,20,32,36,4O,44,64,68,72,76,88,92,96,100,120,124,128,132,144,148,152,156,176,180,184,188,200,204,208,212,288,292,296,300,312,316,320,324,344,348,352,356,368,372,376,380,400,404,408,412,424,428,432,436,456,460,464,468,480,484,488,492(Lmax-64)在一个半帧中的SSB索引，按时间顺序，从O开始编号，到7。UE依据PBCH的DMRS来解析一对一映射半帧中的SSB索引，比如UE可以探测到2LBS或3LBS。对于初始小区选择，UE可以假设具有SS/PBCH块的半帧以2帧的周期出现。
