rmc = struct;% RMC config structurermc.RC ='R.5';% Base configuration on RMC R.5rmc.DuplexMode ='TDD';% User Time Division Duplex (TDD)rmc.TotSubframes = 1;% Configure a single subframe% Generate the base configuration from RMC R.5 and amend to set the% parameters required for the Port7-14 transmission scheme. Note that if% the standard defined RMCs using Port7-14 transmission scheme supported by% lteRMCDL is used, these parameters will be pre-configured.rmc = lteRMCDL(rmc); rmc.NDLRB = 25;% 25 Resource Blocksrmc.NCellID = 10;% Cell identity 10rmc.PDSCH.TxScheme ='Port7-14';% Up to 8 layer transmission, ports 7-14rmc.PDSCH.NLayers = 2;% 2 transmission layers for beamformingrmc.PDSCH.NSCID = 0;% Scrambling identity 0rmc.CSIRefP = 8;% 8 CSI-RS portsrmc.CSIRSConfig = 0;% CSI-RS configuration 0rmc.CSIRSPeriod ='On';% Configure CSI-RS always 'on'rmc.ZeroPowerCSIRSPeriod ='Off';% Configure Zero Power CSI-RS 'off'rmc.PDSCH.PRBSet = (4:8).';% 5 allocated RBsrmc.PDSCH.PMIMode ='Wideband';% Wideband PMI modermc.PDSCH.CSI ='On';% CSI scaling of soft bits%引入子集定义允许所有电报密码本entriesrmc.PDSCH.CodebookSubset ='0x1FFFFFFFFFFFFFFFFFFFFFFFFFFF';

channel = struct;% Channel config structure通道。Seed = 8;% Channel seed通道。NRxAnts = 3;% 3 receive antennas通道。DelayProfile ='EVA';% Delay profile通道。DopplerFreq = 5.0;% Doppler frequency in Hz通道。MIMOCorrelation ='Medium';% Multi-antenna correlation通道。NTerms = 16;% Oscillators used in fading model通道。ModelType ='GMEDS';% Rayleigh fading model type通道。InitTime = 0.0;% Initial time通道。InitPhase ='Random';% Random initial phases通道。NormalizePathGains ='On';% Normalize delay profile power通道。NormalizeTxAnts ='On';% Normalize for transmit antennas

cec = struct;% Channel estimation config structurecec.PilotAverage ='UserDefined';% Type of pilot symbol averagingcec.FreqWindow = 1;% Frequency window size (special mode)cec.TimeWindow = 2;% Time window size (special mode)cec.InterpType ='Cubic';% 2D interpolation typecec.InterpWindow ='Centered';% Interpolation window typecec.InterpWinSize = 1;% Interpolation window size

% Transmit without then with CSI-RS-based PMI feedbackforcsirsFeedback = 0:1% Configure random number generatorsrng('default');% Configure PDSCH substructure with transmission beamforming matrix W.% In the first iteration of the loop transmit each layer on one of the% 8 antennas. In the second iteration, transmit the layers on 2 beams% matched to the channel response using CSI-RS-based PMI feedback. The% PMI fed back to the second iteration is calculated at the end of the% firstif~csirsFeedback rmc.PDSCH.W = [1 0 0 0 0 0 0 0;...0 0 0 0 1 0 0 0]/sqrt(2);elsermc.PDSCH.W = lteCSICodebook(rmc.PDSCH.NLayers,...rmc.CSIRefP, [PMI(1) PMI(2)]).';end% Generate transmission with PDSCH with the beamforming matrix W, onto% 1st of 8 antenna planes (note that CellRefP = 1 for this RMC). The% transmitted grid contains UE-specific reference signal (UE-RS / DMRS)% for channel estimation and CSI-RS reference signal for PMI selection[~, txGrid, rmcinfo] = lteRMCDLTool(rmc, [1;0;0;1]); channel.SamplingRate = rmcinfo.SamplingRate;% OFDM modulation. The additional 25 samples added to the end of the% waveform are to cover the range of delays expected from the channel% modeling (a combination of implementation delay and channel delay% spread)[txWaveform, ofdmDims] = lteOFDMModulate(rmc, txGrid, 0); txWaveform = [txWaveform; zeros(25, size(txWaveform,2))];%#ok% Fading channelrxWaveform = lteFadingChannel(channel, txWaveform);% Create and apply additive white Gaussian noiseif~csirsFeedback SNRdB = 27; SNR = 10^(SNRdB/20); N = 1/(sqrt(2.0*rmc.CSIRefP*double(ofdmDims.Nfft))*SNR); v = N*complex(randn(size(rxWaveform)), randn(size(rxWaveform)));endrxWaveform = rxWaveform + v;% Perform synchronizationoffset = lteDLFrameOffset(rmc, rxWaveform); rxWaveform = rxWaveform(1+offset:end, :);% Perform OFDM demodulation on the received data to recreate the% resource gridrxGrid = lteOFDMDemodulate(rmc, rxWaveform);% Channel estimation using the UE-specific DMRS for PDSCH receptioncec.Reference ='DMRS'; [hest, nest] = lteDLChannelEstimate(rmc, rmc.PDSCH, cec, rxGrid);% Equalize (back to layers) and demodulate the PDSCH.% Extract REs corresponding to the 2 layers of the PDSCH from the given%子帧所有接收天线和通道estimates.ind = ltePDSCHIndices(rmc, rmc.PDSCH, rmc.PDSCH.PRBSet); [pdschRx, pdschHest] = lteExtractResources(ind, rxGrid, hest); [rxBits, rxSymbols] = ltePDSCHDecode(rmc, rmc.PDSCH,...pdschRx, pdschHest, nest);% Compute singular values of the channel and calculate SNRH = squeeze(mean(pdschHest)); d = svd(H);% Print singular values and effective channel SNRifcsirsFeedback label ='8 antenna transmission with CSI-RS-based PMI feedback';elselabel ='8 antenna transmission, 1 antenna for each layer';endfprintf('%s:\n\n', label); svdb = sprintf(' %0.2fdB', 20*log10(d)); fprintf(' Channel singular values:%s\n', svdb); fprintf(' Effective channel SNR: %0.2fdB\n',...SNRdB+10*log10(rmc.PDSCH.NLayers)+10*log10(sum(d.^2)));% Regenerate PDSCH from hard bit decisions and demodulate to estimate% transmitted symbolsremod = ltePDSCH(rmc, rmc.PDSCH, rxBits{1}>0); [rxBitsRef, rxSymbolsRef] = ltePDSCHDecode(rmc, rmc.PDSCH, remod);% Use EVM measurement to estimate SNREVM = comm.EVM; evmRMS = EVM(rxSymbolsRef{1},rxSymbols{1}); SNRest = 20*log10(1/(evmRMS/100)); fprintf('SNR estimate from receiver EVM: %0.2fdB\n\n',SNRest);% Now compute PMI (via CSI-RS) for use in second iteration. Channel% realization remains the sameif~csirsFeedback% Channel estimation via CSI-RS for PMI selectioncec.Reference ='CSIRS'; [hestPMI, nestPMI] = lteDLChannelEstimate(rmc, rmc.PDSCH,...cec, rxGrid);% PMI selectionPMI = ltePMISelect(rmc, rmc.PDSCH, hestPMI, nestPMI);end% Plot received constellationfigure(csirsFeedback+1); plot(rxSymbols{1},'o','MarkerEdgeColor', [0.75 0 0],...'MarkerFaceColor', [1 0.25 0.25],'MarkerSize',3); axis([-1.25 1.25 -1.25 1.25]); title(label);end