PDSCH吞吐量基于Non-Codebook MU-MIMO Transmission Mode 9 (TM9)

NFrames = 2;% Number of framesSNRIn = [8 14];% SNR range in dBNUsers = 2;% Number of active usersNTxAnts = 2;%的数量在eNodeB天线% Specify UE-specific parametersmuNumLayers = [1 1 1 1];% Number of layers for a maximum of 4 usersmuNumRxAnts = [1 1 1 1];% Number of receive antennas for a maximum of 4 usersmuCodeRate = [0.5 0.5 0.5 0.5];% Code rate for a maximum of 4 usersmuModulation = {'16QAM';'16QAM';'16QAM';'16QAM'};% Modulation for a maximum of 4 users

% Initialize cell arrays of PDSCH transmission configuration structures,% transport block sizes and coded transport block sizes.muPDSCH = cell(NUsers,1); trBlkSizes = cell(NUsers,1); codedTrBlkSizes = cell(NUsers,1); simulationParameters = [];% clear simulation parameterssimulationParameters.NDLRB = 50; simulationParameters.PDSCH.PRBSet = (0)'; simulationParameters.PDSCH.DCIFormat ='Format2C'; simulationParameters.PDSCH.TxScheme ='Port7-14'; simulationParameters.PDSCH.NTxAnts = NTxAnts; simulationParameters.DuplexMode ='FDD';% 'FDD', 'TDD'simulationParameters.TotSubframes = 1;% PDSCH configuration structure for users based on the common and% user-specific parametersncw = zeros(NUsers,1);foruserIdx = 1:NUsers simulationParameters.PDSCH.TargetCodeRate = muCodeRate(userIdx); simulationParameters.PDSCH.Modulation = muModulation{userIdx}; simulationParameters.PDSCH.NLayers = muNumLayers(userIdx);% Initialize W to zerosimulationParameters.PDSCH.W = zeros(muNumLayers(userIdx),NTxAnts);% Downlink reference measurement channel configurationenb = lteRMCDL(simulationParameters);% PDSCH transmission configuration structure for usersmuPDSCH{userIdx}= enb.PDSCH;% Number of codewords for usersncw(userIdx) = length(muPDSCH{userIdx}.Modulation);% Store transport block sizes for userstrBlkSizes{userIdx} = muPDSCH{userIdx}.TrBlkSizes;end% Assign redundancy version sequencervSequence = muPDSCH{1}.RVSeq;

hMultiUserParameterSummary(enb,muPDSCH,muNumRxAnts);

muChannel = cell(NUsers,1); channel = struct; channel.DelayProfile ='EPA';% Delay profilechannel.MIMOCorrelation ='Low';% Multi-antenna correlationchannel.NTerms = 16;% Oscillators used in fading modelchannel.ModelType ='GMEDS';%瑞利衰落模型类型channel.InitPhase ='Random';% Random initial phaseschannel.NormalizePathGains ='On';% Normalize delay profile powerchannel.NormalizeTxAnts ='On';% Normalize for transmit antennas

ofdmInfo = lteOFDMInfo(enb); channel.SamplingRate = ofdmInfo.SamplingRate;% Independent channel configuration parameters for each userchanSeeds = [1111 2222 3333 4444];% Channel seed for a maximum of 4 usersdopplerFreq = [5 50 25 15];% Doppler frequency for a maximum of 4 usersforuserIdx = 1:NUsers muChannel{userIdx}= channel; muChannel{userIdx}.Seed = chanSeeds(userIdx);% Channel seedmuChannel{userIdx}.NRxAnts = muNumRxAnts(userIdx);% Number of receive antennasmuChannel{userIdx}.DopplerFreq = dopplerFreq(userIdx);% Doppler frequencyend

%初始化变量用于模拟和analysismaxThroughput = zeros(length(SNRIn),NUsers); simThroughput = zeros(length(SNRIn),NUsers); harqProcesses = cell(NUsers,1);% Initialize cell array for constellation plotrxConstellation = cell(numel(SNRIn),NUsers,2);% Copy the channel cell array and cell array of PDSCH transmission% configuration structure to optimize parallel processing (only if running% the example with Parallel Computing Toolbox)muChannelInit = muChannel; muPDSCHInit = muPDSCH;% During the simulation, some fields of enb will be updated, make a copy to% reinitialize it when simulating each SNR pointenbInit = enb;% For TDD precalculate vector of subframe types: D, S and U for downlink,% special, and uplink, respectivelyifstrcmpi(enb.DuplexMode,'TDD') subframeType = char(10,1); initialSubframeNo = enb.NSubframe;forsNo=0:9% for all subframes in a frameenb.NSubframe = sNo; duplexInfo = lteDuplexingInfo(enb); subframeType(sNo+1) = duplexInfo.SubframeType(1);% first char: D, S or Uendenb.NSubframe = initialSubframeNo;end% CFI can be a scalar, or a vector of length 10 (corresponding to a frame)% if the CFI varies per subframe. If CFI is scalar, create a local copy of% CFI as a vector (one value per subframe).ifnumel(enb.CFI) == 1 CFI = repmat(enb.CFI,1,10);elseCFI = enb.CFI;endforsnrIdx = 1:numel(SNRIn)% Comment out for parallel computing%parfor snrIdx = 1:numel(SNRIn) % Uncomment for parallel computing% Set the random number generator seed depending on the loop variable% to ensure independent random streamsrng(snrIdx,'combRecursive');% Reinitialize enb structures (they are modified during% each SNR point simulation)enb = enbInit;% Reinitialize muChannel and muPDSCH cell arraymuChannel = muChannelInit; muPDSCH = muPDSCHInit;% Initialize the state of all HARQ processesharqProcesses = cell(NUsers,1);foruserIdx = 1:NUsers harqProcesses{userIdx} = hNewHARQProcess(enb,muPDSCH{userIdx});endharqProcessSequence = 1;% Set up variables for the main looplastOffset = zeros(NUsers,1); frameOffset = zeros(NUsers,1); blkCRC = []; rxSymbols = cell(NUsers,2);% DL-SCH symbols for constellation plotbitTput = cell(NUsers,1); txedTrBlkSizes = cell(NUsers,1); W = cell(NUsers,1); pdschIndices = []; pdschRho = 0;% Flag to indicate if a precoding matrix cell array W is available.isWready = false;% Flag to indicate if a subframe is to be processed. Set to true if% there is data to be processed in the subframe, i.e. non-zero transport% block size.processSubframe = false;% Main for loop: for all subframesforsubframeNo = 0:(NFrames*10-1)% Update subframe numberenb.NSubframe = subframeNo;% Load CFI for current subframeenb.CFI = CFI(mod(subframeNo,length(CFI))+1);% Get HARQ process ID for the subframe from HARQ process sequenceharqID = harqProcessSequence(mod(subframeNo,...length(harqProcessSequence))+1);% Channel fading process time offset for the current subframe and% transport block size(s)trBlk = zeros(NUsers,2);% User can have maximum 2 transport blocktrBlkNext = zeros(NUsers,2);foruserIdx = 1:NUsers% Initialize channel fading process time offset for each subframemuChannel{userIdx}.InitTime = subframeNo/1000; trBlk(userIdx,1:ncw(userIdx)) = trBlkSizes{userIdx}(:,mod(subframeNo, 10)+1).';% Get transport block for next subframetrBlkNext(userIdx,1:ncw(userIdx))= trBlkSizes{userIdx}(:,mod(subframeNo+1,10)+1).';end% Set the flag to trigger subframe processingifisWready && any(trBlk(:)) processSubframe = true;elseprocessSubframe = false;end% Precoding matrix calculationifstrcmpi(enb.DuplexMode,'TDD')% Estimate channel in UL subframeifstrcmp(subframeType(mod(subframeNo,10)+1),'U') processSubframe = false;% UL subframe, no DL data% Only perform channel estimate if next subframe is DLifstrcmp(subframeType(mod((subframeNo+1),10)+1),'D') W = hMultiUserPrecodingMatrix(enb,muPDSCH,muChannel); isWready = true;endendelse%FDD% Calculate the precoding matrix for next subframe only if it% carries data (i.e. non-zero trBlkNext)ifany(trBlkNext(:)) W = hMultiUserPrecodingMatrix(enb,muPDSCH,muChannel); isWready = true;elseisWready = false;endend% Subframe processingifprocessSubframe% In this example, the variables pdschRho and pdschIndices will% have the same values for all userscodedTrBlk = zeros(NUsers,2);foruserIdx = 1:NUsers% Update current HARQ process for all usersharqProcesses{userIdx}(harqID) = hHARQScheduling(...harqProcesses{userIdx}(harqID), subframeNo, rvSequence);% Map precoding matrix of all users into PDSCH configuration% cell arraymuPDSCH{userIdx}.W = W{userIdx};% PDSCH resource element power allocation in dBpdschRho = muPDSCH{userIdx}.Rho;%生成指数佛r mapping of PDSCH symbols on resource% grid[pdschIndices,pdschInfo] = ltePDSCHIndices(enb,...muPDSCH{userIdx},muPDSCH{userIdx}.PRBSet);% Obtain coded transport block sizecodedTrBlk(userIdx,1:ncw(userIdx)) = pdschInfo.G;end% Generate grid without any PDSCH mapped[~,txGrid,enbOut] = lteRMCDLTool(enb,[]);% Get the HARQ ID sequence from 'enbOut' for HARQ processingharqProcessSequence = enbOut.PDSCH.HARQProcessSequence;% Generate complex-valued modulated symbol for PDSCH in multi-user% MIMO transmission with block-diagonalization precodingpdschSymbols = hMultiUserPDSCH(enb,muPDSCH,codedTrBlk,...harqProcesses,harqID); powerAdjPerRE = 10^(pdschRho/20);% Perform PDSCH symbols mapping on resource gridtxGrid(pdschIndices) = pdschSymbols*powerAdjPerRE;% Perform OFDM modulation[waveform,ofdmInfo] = lteOFDMModulate(enb,txGrid);% Add 25 sample padding. This is to cover the range of delays% expected from channel modeling (a combination of% implementation delay and channel delay spread)txWaveform = [waveform; zeros(25,NTxAnts)];% Calculate noise gain including compensation for downlink% power allocationSNR = 10^((SNRIn(snrIdx)-muPDSCH{userIdx}.Rho)/20);% Normalize noise power to take account of sampling rate,% which is a function of the IFFT size used in OFDM% modulation, and the number of antennasN0 = 1/(sqrt(2.0*NTxAnts*double(ofdmInfo.Nfft))*SNR);% Pass the waveform through noisy fading channels and receiver% operations for each userforuserIdx = 1:NUsers% Pass data through channel modelrxWaveform = lteFadingChannel(muChannel{userIdx},txWaveform);% Create additive white Gaussian noisenoise = N0*complex(randn(size(rxWaveform)),...randn(size(rxWaveform)));% Add AWGN to the received time domain waveformrxWaveform = rxWaveform + noise;% Receiver% Synchronization offset, OFDM demodulation,% perfect channel estimation, PDSCH and DL-SCH Decoding[harqProcesses{userIdx},dlschSymbols,lastOffset(userIdx)]...= hReceiverOperations(enb,muPDSCH{userIdx},rxWaveform,...muChannel{userIdx},harqProcesses{userIdx},trBlk(userIdx,...1:ncw(userIdx)),lastOffset(userIdx),harqID,subframeNo,noise);% Store the decoded DLSCH symbols for constellation% plottingrxSymbols{userIdx,1} = [rxSymbols{userIdx,1}; dlschSymbols{1}(:)];ifncw(userIdx)>1 rxSymbols{userIdx,2} = [rxSymbols{userIdx,2}; dlschSymbols{2}(:)];end% Store values to calculate throughput% Only for subframes with dataif(任何(trBlk (userIdx, 1:作战飞机(userIdx))) ~ = 0) blkCRC =[blkCRC harqProcesses{userIdx}(harqID).blkerr]; bitTput{userIdx} = [bitTput{userIdx}...trBlk(userIdx,1:ncw(userIdx)).*(1-harqProcesses{userIdx}(harqID).blkerr)]; txedTrBlkSizes{userIdx} = [txedTrBlkSizes{userIdx}...trBlk(userIdx,1:ncw(userIdx))];endendendend% Calculate the maximum and simulated throughputmaxTput = zeros(NUsers,1); simTput = zeros(NUsers,1);foruserIdx = 1:NUsers maxTput(userIdx) = sum(txedTrBlkSizes{userIdx});% Max possible throughputsimTput(userIdx) = sum(bitTput{userIdx},2);% Simulated throughput% Display the results dynamically in the command windowfprintf('\nSNR = %.2f dB. Throughput for UE-%d %d Frame(s) = %.4f Mbps\n',...SNRIn(snrIdx),userIdx,NFrames,1e-6*simTput(userIdx)/(NFrames*10e-3)); fprintf('SNR = %.2f dB. Throughput(%%) for UE-%d %d Frame(s) = %.4f %%\n',...SNRIn(snrIdx),userIdx, NFrames,simTput(userIdx)*100/maxTput(userIdx));endmaxThroughput(snrIdx,:) = maxTput; simThroughput(snrIdx,:) = simTput; rxConstellation(snrIdx,:,:)= rxSymbols;end% Plot received symbol constellationforsnrIdx = 1:numel(SNRIn) ii = 1; figure;foruserIdx = 1:NUsers subplot(NUsers,max(ncw),ii); plot(rxConstellation{snrIdx,userIdx,1},'.r'); title(['User 'num2str(userIdx)', Codeword 1, SNR '...num2str(SNRIn(snrIdx))' dB']); xlabel('In-Phase'); ylabel('Quadrature'); gridon;ifsize(rxConstellation{snrIdx,userIdx,2})~=0 ii = ii+1; subplot(NUsers,max(ncw),ii); plot(rxConstellation{snrIdx,userIdx,2},'.r'); title(['User 'num2str(userIdx)', Codeword 2, SNR '...num2str(SNRIn(snrIdx))' dB']); xlabel('In-Phase'); ylabel('Quadrature'); gridon;endii = ii+1;endend

legendString = cell(NUsers,1); figure;foruserIdx = 1:NUsers plot(SNRIn, simThroughput(:,userIdx)*100./maxThroughput(:,userIdx),'*-.'); holdon; legendString{userIdx} = strcat('UE-',num2str(userIdx),': ',...num2str(muNumLayers(userIdx)),' layer(s), ',num2str(NTxAnts),...' TxAnt(s), ', num2str(muNumRxAnts(userIdx)),' RxAnt(s)');endgridon; xlabel('SNR (dB)'); ylabel('Throughput (%)'); legend(legendString,'Location','SouthEast');