LTE的小区搜索MATLAB仿真程序

function [SssResult, SssCorr] = SssSearch(TimeDataIn,PssResult,ConfigPara,DebugPara) %********************************************************************** % 函数名称：SssSearch % 功能描述： SSS 相关搜索 接收天线数可配置 % 输入参数： % TimeDataIn: 时域采样信号 默认为1.92MSas/s % 输出参数： % SssResult ： SSS搜索结果 % 修改日期 版本号 修改人 修改内容 %----------------------------------------------- % 2018/10/23 V1.0 liangyao 创建 %********************************************************************** SssThr = ConfigPara.SssThr; FixTOCompEn = ConfigPara.FixTOCompEn;%固定补偿FFT定时提前FftDelay引起的相位差 DownSampleRate = ConfigPara.DownSampleRate; FftDelay = ConfigPara.FftDelay/DownSampleRate; CompPhasor = exp(1j*2*pi*FftDelay/128*[0:127]); frameType = ConfigPara.frameType; rxAntNum = size(TimeDataIn,1); fftNum = 128; PssLoc = PssResult.PeakPos; PssPower = PssResult.PeakPower; % PssCE = PssResult.PssCE; nID2Success = PssResult.nID2Success; % PssNi = PssResult.PssNi; % FftDelay = ConfigPara.FftDelay/ConfigPara.DownSampleRate; %提取SSS的频域数据 if isequal(frameType,'TDD') SssDist(1) = round((2048*3 + 144*2 + 160)/16); %TDD normal CP % SssDist(2) = round((2048*3 + 512*3)/16); %TDD Extended CP else SssDist(1) = round((2048 + 144)/16); %FDD normal CP % SssDist(4) = round((2048 + 512)/16);%FDD Extended CP end CellValidNum = 0; for cellIdx=1:length(nID2Success) if nID2Success(cellIdx) SssLoc = PssLoc{cellIdx} - SssDist - FftDelay;% SssCorr = []; for candIdx=1:length(SssLoc) if SssLoc(candIdx)>0 %提取频域数据 SssTimeData = TimeDataIn(:,SssLoc(candIdx):SssLoc(candIdx)+fftNum-1); FreqData = zeros(rxAntNum,fftNum); SssFreqData = zeros(rxAntNum,72-10); for rxAntIdx=1:rxAntNum freqDataTemp = fft(SssTimeData(rxAntIdx,:)); if FixTOCompEn freqDataTemp = freqDataTemp .* CompPhasor; end FreqData(rxAntIdx,:) = fftshift(freqDataTemp); SssFreqData(rxAntIdx,:) = FreqData(rxAntIdx,[ 34:64 66:96]); end if isfield(DebugPara,'SssEqEn') && DebugPara.SssEqEn %利用PSS信道估计信息对SSS进行均衡 H = permute(PssResult.PssCE(cellIdx,:,:),[3,2,1]); sigma2 = PssResult.PssNi(cellIdx); for rxAntIdx=1:rxAntNum HAnt = H(rxAntIdx,:); HConj = conj(HAnt); Yh(rxAntIdx,:) = SssFreqData(rxAntIdx,:) .* HConj; HHconj(rxAntIdx,:) = HAnt.*HConj; end SssFreqData = sum(Yh,1)./(sum(HHconj,1) + sigma2); else SssFreqData = SssFreqData; end %168种小区组号以及两种半帧号进行盲搜索 SssCorrTemp = SssCorrCal(SssFreqData,cellIdx); SssCorr(candIdx,:,:,:) = SssCorrTemp; end end %SSS搜索结果整理 TimeLoc = PssLoc{cellIdx}; PssPowerSave = PssPower{cellIdx}; SssResultTemp = SssSearchPeak(SssCorr,SssThr,cellIdx,TimeLoc,PssPowerSave,ConfigPara,DebugPara); if ~isempty(SssResultTemp) Len = length(SssResultTemp); SssResult(CellValidNum+1:CellValidNum+Len) = SssResultTemp; CellValidNum = CellValidNum + Len; end end end if CellValidNum==0 SssResult = []; SssCorr = []; end end function [SssCorr] = SssCorrCal(SssFreqData,SectorId) CellGroupNum = 168; RxAntNum = size(SssFreqData,1); SssCorr = zeros(2,CellGroupNum,RxAntNum); for GroupIdx=1:CellGroupNum for AntIdx=1:RxAntNum %产生本地SSS序列 [~, sss_sf0, sss_sf5] = SyncSymbGen(GroupIdx-1, SectorId-1); %correlation between local sequence and recieval sequence pwrIn = mean(abs(SssFreqData(AntIdx,:)).^2); SssCorr(1,GroupIdx,AntIdx) = mean(bsxfun(@times,SssFreqData(AntIdx,:)/sqrt(pwrIn), sss_sf0)); SssCorr(2,GroupIdx,AntIdx) = mean(bsxfun(@times,SssFreqData(AntIdx,:)/sqrt(pwrIn), sss_sf5)); end end end function [SssSeq] = LocalSss(SectorId) CellGroupNum = 168; SssSeq = zeros(CellGroupNum,2,62); for GroupIdx=1:CellGroupNum %产生本地SSS序列 [~, sss_sf0, sss_sf5] = SyncSymbGen(GroupIdx-1, SectorId-1); SssSeq(GroupIdx,1,:) = sss_sf0; SssSeq(GroupIdx,2,:) = sss_sf5; end end function Exp = SaveSssFreqData(FreqDataIn,AntNum) [mantissa, Exp] = Float2Fixed(FreqDataIn,15,2); fid = fopen('../SaveFile/matlab/FreqDataIn.txt','w'); FreqDataFixed = mantissa; if AntNum == 2 for Idx=1:size(FreqDataFixed,2) fprintf( fid,'%d %d %d %d\n',real(FreqDataFixed(1,Idx)),imag(FreqDataFixed(1,Idx)),real(FreqDataFixed(2,Idx)),imag(FreqDataFixed(2,Idx))); end else for Idx=1:size(FreqDataFixed,2) fprintf( fid,'%d %d\n',real(FreqDataFixed(1,Idx)),imag(FreqDataFixed(1,Idx))); end end fclose(fid); fid = fopen('../SaveFile/matlab/FreqDataScaleIn.txt','w'); for antIdx = 1:length(Exp) fprintf(fid,'%d ',Exp(antIdx)); end fclose(fid); end function [SssResult] = SssSearchPeak(SssCorr,SssThr,cellIdx,TimeLoc,PssPower,ConfigPara,DebugPara) SssResult = []; cellValid = 1; for candIdx=1:size(SssCorr,1) PssTimeLoc = TimeLoc(candIdx); PssPowerTemp = PssPower(candIdx); candiMetric0 = sqrt(squeeze(mean(abs(SssCorr(candIdx,1,:,:)).^2,4))); candiMetric1 = sqrt(squeeze(mean(abs(SssCorr(candIdx,2,:,:)).^2,4))); if max(candiMetric0)>max(candiMetric1) halfFrame = 1; candiMetric = candiMetric0; else halfFrame = 2; candiMetric = candiMetric1; end Idx = find(candiMetric>=SssThr); if ~isempty(Idx) for cIdx=1:length(Idx) GroupId = Idx(cIdx)-1; SssResult(cellValid).sssCorr = candiMetric(Idx(cIdx)); SssResult(cellValid).GroupId = GroupId; SssResult(cellValid).CellId = GroupId*3+(cellIdx-1); SssResult(cellValid).NsubFrame = (halfFrame-1)*5; SssResult(cellValid).PssTimeLoc = PssTimeLoc; SssResult(cellValid).PssPower = PssPowerTemp; SssResult(cellValid).FrameStartPos = PssTimeLoc - (ConfigPara.PssTimeLoc(halfFrame) + 10);% 10 is the length of CP 9 + 1 cellValid = cellValid + 1; end end end % for debug if ~isempty(DebugPara) && DebugPara.SssCorPlotEn ==1 for candIdx=1:size(SssCorr,1) figure; subplot(2,1,1); candiMetric = sqrt(mean(abs(SssCorr(candIdx,1,:,:)).^2,4)); plot(reshape(candiMetric,1,[])); title('The amplitude of SSS correlation for Sf=0'); subplot(2,1,2); candiMetric = sqrt(mean(abs(SssCorr(candIdx,2,:,:)).^2,4)); plot(reshape(candiMetric,1,[])); title('The amplitude of SSS correlation for Sf=5'); end end end