Документация

% Configuration TS 36.101 25 REs (5 MHz), 64-QAM, full allocation
rmc = lteRMCDL('R.6');
rmc.OCNGPDSCHEnable = 'On';

% Create eNodeB transmission with fixed PDSCH data
rng(2);                 % Fixed random seed (arbitrary)
data = randi([0 1], sum(rmc.PDSCH.TrBlkSizes),1);

% Generate 1 frame, to be repeated to simulate a total of N frames
[tx, ~, info] = lteRMCDLTool(rmc, data); % 1 frame

% Calculate the sampling period and the length of the frame.
SamplePeriod = 1/info.SamplingRate;
FrameLength = length(tx);

% Band limiting interpolation filter
FiltOrd = 32;
h = firpm(FiltOrd,[0 2.25e6*2*SamplePeriod 2.7e6*2*SamplePeriod 1],[1 1 0 0]);
FilterDelaySamples = FiltOrd/2; % filter group delay

% Propagation model
SNRdB = 57;                 % Es/Noc in dB
NocdBm = -98;               % Noc in dBm/15kHz
NocdBW = NocdBm - 30;       % Noc in dBW/15kHz57
SNR = 10^(SNRdB/10);        % linear Es/Noc
Es = SNR*(10^(NocdBW/10));  % linear Es per RE
FFTLength = info.Nfft;
SymbolPower = Es/double(FFTLength);

% Number of simulation frames N>=1
N = 3;

% Preallocate vectors for results for N-1 frames
% EVM is not measured in the first frame to avoid transient effects
evmpeak = zeros(N-1,1);   % Preallocation for results
evmrms = zeros(N-1,1);    % Preallocation for results

% Specify and open Simulink model
model = 'RFLTEReceiverModel';
disp('Starting Simulink');
open_system(model);

% Generate test data for RF receiver
time = (0:FrameLength+FilterDelaySamples)*SamplePeriod;
% Append to the end of the frame enough samples to compensate for the delay
% of the filter
txWaveform = timeseries([tx; tx(1:FilterDelaySamples+1)],time);

% Simulate RF Blockset model of RF RX
set_param(model, 'LoadInitialState', 'off');
disp('Simulating');
sim(model, time(end));
% Save the final state of the model in xInitial for next frame processing
xInitial = xFinal;

% Synchronize to received waveform
Offset = lteDLFrameOffset(rmc,squeeze(rx),'TestEVM');
% In this case Offset = FilterDelaySamples therefore the following
% frames do not require synchronization

% Load state after execution of previous frame. Since we are repeating the
% same frame the model state will be the same after every frame execution.
set_param(model, 'LoadInitialState', 'on', 'InitialState','xInitial');
% Modify input vector to take into account the delay of the bandlimiting
% filter
RepeatFrame = [tx(FilterDelaySamples+1:end); tx(1:FilterDelaySamples+1)];
EVMalg.EnablePlotting = 'Off';
cec.PilotAverage = 'TestEVM';

for n = 2:N % for all remaining frames
    % Generate data
    time = ( (n-1)*FrameLength+(0:FrameLength) + FilterDelaySamples)*SamplePeriod;
    txWaveform = timeseries(RepeatFrame,time);

    % Execute Simulink RF Blockset testbench
    sim(model, time(end));
    xInitial = xFinal; % Save model state

    % Compute and display EVM measurements
    evmmeas = hPDSCHEVM(rmc,cec,squeeze(rx),EVMalg);
    evmpeak(n-1) = evmmeas.Peak;
    evmrms(n-1) = evmmeas.RMS;
end

figure;
plot((2:N), 100*evmpeak,'o-')
title('EVM peak %');
xlabel('Number of frames');
figure;
plot((2:N), 100*evmrms,'o-');
title('EVM RMS %');
xlabel('Number of frames');

bdclose(model);
clear([model,'_acc']);