rng('default'); % Reset the random number generator
simParameters = []; % Clear the simParameters variable
simParameters.NumFramesSim = 30; % Simulation time in terms of number of 10 ms frames
simParameters.SchedulingType = 0; % Set the value to 0 (slot based scheduling) or 1 (symbol based scheduling)

% Number of UEs in the simulation. UEs are assumed to have sequential radio
% network temporary identifiers (RNTIs) from 1 to NumUEs. If you change the
% number of UEs, ensure that the following simulation parameters are array
% of length equal to NumUEs: simParameters.UEDistance,
% simParameters.ULPacketPeriodicityUEs, simParameters.ULPacketSizesUEs,
% simParameters.DLPacketPeriodicityUEs, simParameters.DLPacketSizesUEs
simParameters.NumUEs = 4;
simParameters.UEDistance = [100; 400; 1500; 1000];

% Set the channel bandwidth to 5 MHz and subcarrier spacing (SCS) to 15
% kHz as defined in 3GPP TS 38.104 Section 5.3.2
% RB count for 5 MHz band with 15 kHz SCS. The complete
% bandwidth is assumed to be allotted for PUSCH/PDSCH
simParameters.NumRBs = 25;
simParameters.SCS = 15; % kHz
simParameters.DLCarrierFreq = 2.635e9; % Hz
simParameters.ULCarrierFreq = 2.515e9; % Hz
% The UL and DL carriers are assumed to have symmetric channel
% bandwidth
simParameters.DLBandwidth = 5e6; % Hz
simParameters.ULBandwidth = 5e6; % Hz

simParameters.UETxPower = 23; % Tx power for all the UEs in dBm
simParameters.GNBTxPower = 29; % Tx power for gNB in dBm
simParameters.GNBRxGain = 11; % Receiver antenna gain at gNB

% SINR to CQI mapping table for 0.1 BLER
simParameters.SINR90pc = [-5.46 -0.46 4.54 9.05 11.54 14.04 15.54 18.04 ...
    20.04 22.43 24.93 25.43 27.43 30.43 33.43];

simParameters.SchedulerStrategy = 'PF'; % Supported scheduling strategies: 'PF', 'RR', and 'BestCQI'
% Maximum limit on the RBs allotted for PUSCH and PDSCH
% Transmission limit is applicable for new PUSCH and PDSCH assignments and
% not for the retransmissions
simParameters.RBAllocationLimitUL = 15; % For PUSCH
simParameters.RBAllocationLimitDL = 15; % For PDSCH

% Logging and Visualization Configuration
% The parameters CQIVisualization and RBVisualization control the display
% of these visualizations: (i) CQI visualization of RBs (ii) RB assignment
% visualization. By default, the 'RBVisualization' plot is disabled. You
% can enable it by setting to 'true'
simParameters.CQIVisualization = true;
simParameters.RBVisualization = false;
% The output metrics plots are updated periodically NumMetricsSteps times within the simulation duration
simParameters.NumMetricsSteps = 20;
% MAT-files to write the logs into. They are used for post simulation analysis and visualization
simParameters.ParametersLogFile = 'simParameters'; % For logging the simulation parameters
simParameters.SimulationLogFile = 'simulationLogs'; % For logging the simulation logs

% Enable packet capture (PCAP)
simParameters.PCAPLogging = false; % Set the value to true to enable packet capture for UEofInterest
simParameters.UEofInterest = 1; % Log the packets of UE with this RNTI

% Set the periodic UL and DL application traffic pattern for UEs
simParameters.ULPacketPeriodicityUEs = [10; 20; 20; 30]; % Periodicity (in ms) at which the UL packets are generated by UEs
simParameters.ULPacketSizesUEs = [8000; 8000; 7500; 8500]; % Size of the UL packets (in bytes) generated by UEs
simParameters.DLPacketPeriodicityUEs = [10; 20; 30; 30]; % Periodicity (in ms) at which the DL packets are generated for UEs at gNB
simParameters.DLPacketSizesUEs = [10000; 9000; 7500; 7500]; % Size of the DL packets generated (in bytes) for UEs at gNB
% Validate the simulation configuration
hNRCellPerformanceWithPhysicalLayerValidateConfig(simParameters);

simParameters.DuplexMode = 0; % FDD
simParameters.NCellID = 1; % Physical cell ID
simParameters.Position = [0 0 0]; % Position of gNB in (x,y,z) coordinates
simParameters.CSIRSRowNumber = 2; % Possible row numbers for single transmit antenna case are 1 and 2
simParameters.SubbandSize = 8; % Size of sub-band for CQI reporting in terms of number of RBs
simParameters.ChannelModelType = 'CDL'; % To model CDL propagation channel
% gNB ensures that PUSCH assignment is received at UEs PUSCHPrepTime ahead
% of the transmission time
simParameters.PUSCHPrepTime = 200; % In microseconds
% Slot duration for the selected SCS and number of slots in a 10 ms frame
slotDuration = 1/(simParameters.SCS/15); % In ms
numSlotsFrame = 10/slotDuration; % Number of slots in a 10 ms frame
numSlotsSim = simParameters.NumFramesSim * numSlotsFrame; % Number of slots in the simulation

% Interval at which metrics visualization updates in terms of number of
% slots. As one slot is the finest time-granularity of the simulation, make
% sure that MetricsStepSize is an integer
simParameters.MetricsStepSize = ceil(numSlotsSim / simParameters.NumMetricsSteps);
if mod(numSlotsSim, simParameters.NumMetricsSteps) ~= 0
    % Update the NumMetricsSteps parameter if NumSlotsSim is not
    % completely divisible by it
    simParameters.NumMetricsSteps = floor(numSlotsSim / simParameters.MetricsStepSize);
end

numLogicalChannels = 1; % Only 1 logical channel is assumed in each UE in this example
% Logical channel id (logical channel ID of data radio bearers starts from 4) 
simParameters.LCHConfig.LCID = 4;

% RLC entity direction. Value 0 represents DL only, 1
% represents UL only and 2 represents both UL and DL
% direction. Setting entity direction to have both UL and DL
simParameters.RLCConfig.EntityDir = 2;

% Create RLC channel configuration structure
rlcChannelConfigStruct.LCGID = 1; % Mapping between logical channel and logical channel group ID
rlcChannelConfigStruct.Priority = 1; % Priority of each logical channel
rlcChannelConfigStruct.PBR = 8; % Prioritized bitrate (PBR), in kilobytes per second, of each logical channel
rlcChannelConfigStruct.BSD = 10; % Bucket size duration (BSD), in ms, of each logical channel
rlcChannelConfigStruct.EntityType = simParameters.RLCConfig.EntityDir;
rlcChannelConfigStruct.LogicalChannelID = simParameters.LCHConfig.LCID;

% Maximum RLC SDU length (in bytes) as per 3GPP TS 38.323
simParameters.maxRLCSDULength = 9000;

if ~isfield(simParameters, 'SchedulingType') || simParameters.SchedulingType == 0 % If no scheduling type is specified or slot based scheduling is specified
    rbAssignmentPlotPeriodicity = numSlotsFrame; % Update RB assignment visualization every frame (10 ms)
    tickGranularity = 14;
    simParameters.PUSCHMappingType = 'A';
    simParameters.PDSCHMappingType = 'A';
else % Symbol based scheduling
    rbAssignmentPlotPeriodicity = 1; % Update RB assignment visualization every slot
    tickGranularity = 1;
    simParameters.PUSCHMappingType = 'B';
    simParameters.PDSCHMappingType = 'B';
end

gNB = hNRGNB(simParameters); % Create gNB node
% Create scheduler
switch(simParameters.SchedulerStrategy)
    case 'RR' % Round robin scheduler
        scheduler = hNRSchedulerRoundRobin(simParameters);
    case 'PF' % Proportional fair scheduler
        scheduler = hNRSchedulerProportionalFair(simParameters);
    case 'BestCQI' % Best CQI scheduler
        scheduler = hNRSchedulerBestCQI(simParameters);
end
addScheduler(gNB, scheduler); % Add scheduler to gNB

gNB.PhyEntity = hNRGNBPhy(simParameters); % Create the PHY layer instance
configurePhy(gNB, simParameters); % Configure the PHY layer
setPhyInterface(gNB); % Set the interface to PHY layer

% Create the set of UE nodes
UEs = cell(simParameters.NumUEs, 1);
for ueIdx=1:simParameters.NumUEs
    simParameters.Position = [simParameters.UEDistance(ueIdx) 0 0]; % Position of UE
    UEs{ueIdx} = hNRUE(simParameters, ueIdx);
    UEs{ueIdx}.PhyEntity = hNRUEPhy(simParameters, ueIdx); % Create the PHY layer instance
    configurePhy(UEs{ueIdx}, simParameters); % Configure the PHY layer
    setPhyInterface(UEs{ueIdx}); % Set up the interface to PHY layer

    % Setup logical channel at gNB for the UE
    configureLogicalChannel(gNB, ueIdx, rlcChannelConfigStruct);
    % Setup logical channel at UE
    configureLogicalChannel(UEs{ueIdx}, ueIdx, rlcChannelConfigStruct);

    % Add data traffic pattern generators to gNB and UE nodes
    ulPacketSize = simParameters.ULPacketSizesUEs(ueIdx);
    % Calculate the data rate (in kbps) of On-Off traffic pattern using
    % packet size (in bytes) and packet interval (in ms)
    ulDataRate = ceil(1000/simParameters.ULPacketPeriodicityUEs(ueIdx)) * ulPacketSize * 8e-3;
    % Limit the size of the generated application packet to the maximum RLC
    % SDU size. The maximum supported RLC SDU size is 9000 bytes
    if ulPacketSize > simParameters.maxRLCSDULength
        ulPacketSize = simParameters.maxRLCSDULength;
    end

    % Create an object for On-Off network traffic pattern and add it to the
    % specified UE. This object generates the uplink data traffic on the UE
    ulApp = networkTrafficOnOff('PacketSize', ulPacketSize, 'GeneratePacket', true, ...
        'OnTime', simParameters.NumFramesSim/100, 'OffTime', 0, 'DataRate', ulDataRate);
    UEs{ueIdx}.addApplication(ueIdx, simParameters.LCHConfig.LCID, ulApp);

    dlPacketSize = simParameters.DLPacketSizesUEs(ueIdx);
    dlDataRate = ceil(1000/simParameters.DLPacketPeriodicityUEs(ueIdx)) * dlPacketSize *8e-3;
    if dlPacketSize > simParameters.maxRLCSDULength
        dlPacketSize = simParameters.maxRLCSDULength;
    end

    % Create an object for On-Off network traffic pattern for the specified
    % UE and add it to the gNB. This object generates the downlink data
    % traffic on the gNB for the UE
    dlApp = networkTrafficOnOff('PacketSize', dlPacketSize, 'GeneratePacket', true, ...
        'OnTime', simParameters.NumFramesSim/100, 'OffTime', 0, 'DataRate', dlDataRate);
    gNB.addApplication(ueIdx, simParameters.LCHConfig.LCID, dlApp);
end
% Setup the UL and DL packet distribution mechanism
simParameters.MaxReceivers = simParameters.NumUEs;
% Create DL packet distribution object
dlPacketDistributionObj = hNRPacketDistribution(simParameters, 0); % 0 for DL
% Create UL packet distribution object
ulPacketDistributionObj = hNRPacketDistribution(simParameters, 1); % 1 for UL
hNRSetUpPacketDistribution(simParameters, gNB, UEs, dlPacketDistributionObj, ulPacketDistributionObj);

% Enable PCAP logging
if simParameters.PCAPLogging
    % To generate unique file name for every simulation run
    ueCapturefileName = strcat('CellID-', num2str(simParameters.NCellID), '_ue-',num2str(simParameters.UEofInterest), '_', num2str(now));
    enablePacketLogging(UEs{simParameters.UEofInterest}.PhyEntity, ueCapturefileName);
    
    % Uncomment the below code to enable packet capture at gNB
    % gnbCapturefileName = strcat('CellID-', num2str(simParameters.NCellID), '_gNB-', num2str(now));
    % enablePacketLogging(gNB.PhyEntity, gnbCapturefileName);
end

% Create an object for MAC (UL & DL) scheduling information visualization and logging
simSchedulingLogger = hNRSchedulingLogger(simParameters);
% Create an object for PHY metrics logging
simPhyLogger = hNRPhyLogger(simParameters);
% Create visualization object for MAC and PHY metrics
visualizer = hNRMetricsVisualizer(simParameters, 'MACLogger', simSchedulingLogger, 'PhyLogger', simPhyLogger);

% Run processing loop
slotNum = 0;
numSymbolsSim = numSlotsSim * 14; % Simulation time in units of symbol duration
% Execute all the symbols in the simulation
for symbolNum = 1 : tickGranularity : numSymbolsSim
    if mod(symbolNum - 1, 14) == 0
        slotNum = slotNum + 1;
    end
    
    % Run MAC and PHY of gNB
    run(gNB);
    
    % Run MAC and PHY of UEs
    for ueIdx = 1:simParameters.NumUEs
        run(UEs{ueIdx});
    end
    
    % MAC logging
    logCellSchedulingStats(simSchedulingLogger, symbolNum, gNB, UEs);
    
    % PHY logging
    logCellPhyStats(simPhyLogger, symbolNum, gNB, UEs);
    
    % Visualization
    % Check slot boundary
    if symbolNum > 1 && ((simParameters.SchedulingType == 1 && mod(symbolNum, 14) == 0) || (simParameters.SchedulingType == 0 && mod(symbolNum-1, 14) == 0))
        % RB assignment visualization (if enabled)
        if simParameters.RBVisualization
            if mod(slotNum, rbAssignmentPlotPeriodicity) == 0
                % Plot at slot boundary, if the update periodicity is reached
                plotRBGrids(simSchedulingLogger);
            end
        end
        % CQI grid visualization (if enabled)
        if simParameters.CQIVisualization
            if mod(slotNum, numSlotsFrame) == 0 % Plot at frame boundary
                plotCQIRBGrids(simSchedulingLogger);
            end
        end
        % If the update periodicity is reached, plot scheduler metrics and PHY metrics visualization
        % at slot boundary
        if mod(slotNum, simParameters.MetricsStepSize) == 0
            plotMetrics(visualizer, slotNum);
        end
    end
    
    % Advance timer ticks for gNB and UEs by 14 symbols
    advanceTimer(gNB, tickGranularity);
    for ueIdx = 1:simParameters.NumUEs
        advanceTimer(UEs{ueIdx}, tickGranularity);
    end
end

simulationLogs = cell(1,1);
if(simParameters.DuplexMode == 0) % FDD
    logInfo = struct('DLTimeStepLogs', [], 'ULTimeStepLogs', [], 'SchedulingAssignmentLogs', [], 'BLERLogs', [], 'AvgBLERLogs', []);
else
    logInfo = struct('TimeStepLogs', [], 'SchedulingAssignmentLogs', [], 'BLERLogs', []);
end
[dlStats, ulStats] = getPerformanceIndicators(simSchedulingLogger);
[logInfo.BLERLogs, logInfo.AvgBLERLogs] = getBLERLogs(simPhyLogger); % Block Error rate logs
fprintf('Peak UL throughput: %0.2f Mbps. Achieved average UL Throughput: %0.2f Mbps', ulStats(1, 1), ulStats(2, 1));

fprintf('\nPeak DL throughput: %0.2f Mbps. Achieved average DL Throughput: %0.2f Mbps', dlStats(1, 1), dlStats(2, 1));

fprintf('\nAchieved average UL Goodput: %0.2f Mbps. Achieved average DL Goodput: %0.2f Mbps', ulStats(5, 1), dlStats(5, 1));

fprintf('\nPeak UL spectral efficiency: %0.2f bits/s/Hz. Achieved average UL spectral efficiency: %0.2f bits/s/Hz ', ulStats(3, 1), ulStats(4, 1));

fprintf('\nPeak DL spectral efficiency: %0.2f bits/s/Hz. Achieved average DL spectral efficiency: %0.2f bits/s/Hz', dlStats(3, 1), dlStats(4, 1));

disp(['Block error rate for each UE in the uplink direction: [' num2str(round(logInfo.AvgBLERLogs(:, 2)', 2)) ']']);

disp(['Block error rate for each UE in the downlink direction: [' num2str(round(logInfo.AvgBLERLogs(:, 1)', 2)) ']']);

% Read the logs and save them in MAT-files
if(simParameters.DuplexMode == 0) % FDD
    [logInfo.DLTimeStepLogs, logInfo.ULTimeStepLogs] = getSchedulingLogs(simSchedulingLogger);
else % TDD
    logInfo.TimeStepLogs = getSchedulingLogs(simSchedulingLogger);
end
logInfo.SchedulingAssignmentLogs = getGrantLogs(simSchedulingLogger); % Scheduling assignments log
simulationLogs{1} = logInfo;
save(simParameters.ParametersLogFile, 'simParameters'); % Save simulation parameters in a MAT-file
save(simParameters.SimulationLogFile, 'simulationLogs'); % Save simulation logs in a MAT-file