commSupportPackageCheck('BLUETOOTH');

% The number of BLE Slaves in connection with the Master
slavesCount = 1;

% Create the BLE Master device capable of connecting with "slavesCount"
% number of Slaves
master = helperBLEDeviceModel('Role','Master', ...
                              'SlavesCount',slavesCount);

% Initialize the channel classification parameters to classify the BLE
% channels into good or bad channels.
% PERThreshold:                 Packet error rate (PER) threshold value
% ClassificationInterval:       Periodicity of channel classification
% RxStatusCount:                Maximum number of received packets status
% MinRxCountToClassify:         Minimum number of received packets status
% BadChannelClassificationMethod: Method for bad channels classification
% PreferredMinimumGoodChannels: Preferred number of good channels
channelClassification = helperBLEChannelClassification(...
                        'PERThreshold',40, ...
                        'ClassificationInterval',150, ...
                        'RxStatusCount',50, ...
                        'MinRxCountToClassify',4, ...
                        'BadChannelClassificationMethod','Reset all the bad channels', ...
                        'PreferredMinimumGoodChannels',30);

% Assign channel classification parameters to the Master device
master.ChannelClassification = channelClassification;

% Initialize "slavesCount" number of Slaves
slaves(1, slavesCount) = helperBLEDeviceModel;

% Create "slavesCount" number of Slave devices
for idx = 1:slavesCount
    slaves(idx) = helperBLEDeviceModel('Role','Slave');
end

% Create "slavesCount" connections between the "Master" and "Slaves". This
% function creates a Link Layer connection by sharing the common connection
% parameters such as connection interval, access address for each
% Master-Slave connection pair.
[master, slaves] = helperBLECreateLLConnection(master, slaves);

% Set number of WLAN networks interfering with the BLE network
wlanNetworksCount = 6;

% Set of WLAN channels (in the range [1, 14]) used by each WLAN network
wlanChannels = [1, 5, 6, 12, 9, 8];
% Probability of collisions of each WLAN network with BLE network
collisionProbabilities = [0.75, 0.68, 0.76, 0.80, 0.78, 0.64];
% Start and end times (in milliseconds) of transmission in each WLAN
% network
wlanInterferencePeriod = [0, inf; ...
    0, inf; ...
    0, 2100; ...
    0, inf; ...
    200, 2800; ...
    150, inf];

% Ratio of WLAN signal power level relative to BLE signal power level
wlanInterferenceLevel = [1.20, 0.90, 0.85, 0.95, 0.70, 1.15];

% Create a configuration object for WLAN traffic
wlanTrafficConfig = helperBLEWLANSignalTrafficConfig();

% Configure WLAN traffic with the specified WLAN network parameters
wlanTraffic(wlanTrafficConfig, wlanNetworksCount, wlanChannels, collisionProbabilities, ...
    wlanInterferencePeriod, wlanInterferenceLevel);

% Initialize simulation parameters

% Reset the random number generator seed
sprev = rng('default');

% To enable the visualization of BLE coexistence with WLAN, set the
% "enableVisualization" to true. To disable the visualization of BLE
% coexistence with WLAN set the "enableVisualization" to false.
enableVisualization = true;

% To enable the visualization of channel hopping sequence, set the
% "enableHoppingVisualization" to true. To disable the visualization of
% channel hopping sequence, set the "enableHoppingVisualization" to false.
% If the "enableVisualization" is set to false, then
% "enableHoppingVisualization" is not considered.
enableHoppingVisualization = true;

% Total simulation time in milliseconds
simulationTime = 4000;

% One step time is considered as 0.025 milliseconds. All the timing
% parameters (connection interval, scan interval, advertising interval,
% etc.) in BLE specification are multiple of 0.625 milliseconds. The
% minimum packet size used in this example is 9 octets (72 bits). The
% packet transmission time in different PHY modes are: 0.072 milliseconds
% (in LE1M), 0.036 milliseconds (in LE2M), 0.144 milliseconds (in LE500K)
% and 0.288 milliseconds (in LE125K). Therefore, the step time is
% considered as 0.025 milliseconds (0.625 is multiple of 0.025) to achieve
% a trade-off between the simulation time and accuracy.
timeStep = 0.025;

% Parameters for generating BLE transmission mode
phyMode = 'LE1M';   % Mode can be 'LE2M' | 'LE1M' | 'LE500K' | 'LE125K'
EbNo = 16;          % Eb/No value in dB

% Initialize PHY parameters
% sps:              Samples per symbol
% bleSNR:           BLE signal to noise ratio
% initImpairments:  System object for BLE PHY impairments
[sps, bleSNR, initImpairments] = helperBLEInitPHYParameters(EbNo, phyMode);

% Create structure for an empty packet to initialize the output of Master
% and Slaves
% LLPDU:        Generated Link Layer Protocol Data Unit (PDU) appended with
%               Cyclic Redundancy Check (CRC)
% RateIndex:    String representing the rate at which the packet will be
%               transmitted. It contains one of 'LE2M' | 'LE1M' | 'LE500K'
%               | 'LE125K'
% AccessAddress:Unique address for each Master-Slave connection pair
% ChannelIndex: Channel on which the packet is transmitted
emptyPacket = struct('LLPDU',[], ...
                     'AccessAddress','', ...
                     'RateIndex','', ...
                     'ChannelIndex',-1);

% Initialize the Slave output
slaveOutput = emptyPacket;

% Preallocate the buffers to store the Slave outputs
slaveOutputs = cell(1, slavesCount);

% Initialize figures for visualization of coexistence model for each Slave.
% This visualization shows the WLAN channels along with their collision
% probabilities and also shows the channel hopping for the communication
% between BLE Master and Slave devices. It also shows the status (good or
% bad) of each BLE channel along with the success rate in the respective
% channel.
coexistenceModel = ...
    helperBLEVisualizeCoexistence(...
    'Action','Initialize', ...
    'SlaveCount',slavesCount, ...
    'WLANChannelList',wlanChannels, ...
    'PERThreshold',master.ChannelClassification.PERThreshold, ...
    'ClassificationInterval',master.ChannelClassification.ClassificationInterval, ...
    'ChannelBusyCountThreshold',master.ChannelClassification.ChannelBusyCountThreshold, ...
    'PreferredMinimumGoodChannels',master.ChannelClassification.PreferredMinimumGoodChannels, ...
    'ConnectionInterval',master.LLConnectionConfigs(1).ConnectionInterval, ...
    'Stoptime',simulationTime, ...
    'PHYMode',phyMode, ...
    'EnableVisualization',enableVisualization, ...
    'EnableHoppingVisualization',enableHoppingVisualization);
coexistenceModel.initializeVisualization();
viewModel(coexistenceModel);
master.CoexistenceVisualization = coexistenceModel;

% Run simulation
for simulationTimer = 0:timeStep:simulationTime
    % Stop the simulation, if all the Slaves are disconnected from the
    % Master due to interference. If the PER of the BLE channels in which
    % they are communicating with each other is high, then the Master and
    % the Slave are disconnected. The PER of the channel is high because of
    % the high collision probability in the respective channel.
    if numel(master.ActiveConnectionIdxs(master.ActiveConnectionIdxs ~= -1)) == 0
        fprintf('Simulation terminated as all Slaves are disconnected from the Master device.\n')
        break;
    end

    % Update WLAN traffic in visualization
    helperBLEUpdateWLANTraffic(slavesCount, wlanChannels, wlanTrafficConfig, simulationTimer, master);

    % MASTER: Transmitting or Receiving mode
    if (master.ActiveChannel == slaveOutput.ChannelIndex) && ...
            ~isempty(slaveOutput.LLPDU)
        masterOutput = run(master, slaveOutput);
    else
        masterOutput = run(master, emptyPacket);
    end

    if ~(isempty(masterOutput.LLPDU))
        % Generate PHY waveform
        masterOutput.RateIndex = phyMode;
        masterWaveformTx = helperBLEPHYTx(masterOutput, sps);

        % Add impairments
        masterWaveformTx = helperBLEImpairments(initImpairments, masterWaveformTx, sps);

        % Add WLAN interference
        masterWaveformTx = addInterference(wlanTrafficConfig, ...
            masterOutput.ChannelIndex, simulationTimer, masterWaveformTx);

        % Pass the transmitted waveform through AWGN channel
        masterWaveformRx = awgn(masterWaveformTx, bleSNR);

        % Decode PHY waveform after adding impairments and interference
        [decodedMasterPacket, decodedMasterAccessAddress] = helperBLEPHYRx(masterWaveformRx, ...
            phyMode, sps, masterOutput.AccessAddress, masterOutput.ChannelIndex);

        masterOutput.LLPDU = decodedMasterPacket;
        % Access address becomes empty when the BLE PHY receiver fails to
        % detect a valid BLE packet due to high interference level or
        % impairments or noise level.
        if ~isempty(decodedMasterAccessAddress)
            masterOutput.AccessAddress = dec2hex(bi2de(decodedMasterAccessAddress'), 8);
        end
    end

    % Update current simulation time
    master.CoexistenceVisualization.CurrentTime = simulationTimer;
    master.CoexistenceVisualization.Action = 'Simulation Progress';

    % SLAVE: Transmitting or Receiving mode
    for idx = 1:slavesCount
        % Pass the "MasterOutput" to the Slave listening in the same
        % frequency
        if (slaves(idx).ActiveChannel == masterOutput.ChannelIndex) && ...
                ~isempty(masterOutput.LLPDU)
            slaveOutputs{idx} = run(slaves(idx), masterOutput);
        % Pass an empty packet to all other Slaves
        else
            slaveOutputs{idx} = run(slaves(idx), emptyPacket);
        end

        % Update simulation progress for each Slave
        master.CoexistenceVisualization.SlaveNumber = idx;
        viewModel(master.CoexistenceVisualization)
    end

    slaveOutput = emptyPacket;

    % Get the active Slave output (At any time instance only one Slave is
    % active)
    for idx = 1:slavesCount
        if ~isempty(slaveOutputs{idx}.LLPDU)
            slaveOutput = slaveOutputs{idx};
            break
        end
    end

    if ~(isempty(slaveOutput.LLPDU))
        % Generate PHY waveform
        slaveOutput.RateIndex = phyMode;
        slaveWaveformTx = helperBLEPHYTx(slaveOutput, sps);

        % Add BLE impairments
        slaveWaveformTx = helperBLEImpairments(initImpairments, slaveWaveformTx, sps);

        % Add WLAN interference
        slaveWaveformTx = addInterference(wlanTrafficConfig, ...
            slaveOutput.ChannelIndex, simulationTimer, slaveWaveformTx);

        % Pass the transmitted waveform through AWGN channel
        slaveWaveformRx = awgn(slaveWaveformTx, bleSNR);

        % Decode PHY waveform after adding impairments and interference
        [decodedSlavePacket, decodedSlaveAccessAddress] = helperBLEPHYRx(slaveWaveformRx, ...
            phyMode, sps, slaveOutput.AccessAddress, slaveOutput.ChannelIndex);

        slaveOutput.LLPDU = decodedSlavePacket;
        % Access address becomes empty when the BLE PHY receiver fails to
        % detect a valid BLE packet due to high interference level or
        % impairments or noise level.
        if ~isempty(decodedSlaveAccessAddress)
            slaveOutput.AccessAddress = dec2hex(bi2de(decodedSlaveAccessAddress'), 8);
        end
    end
end

% Update the simulation progress for each Slave
for idx = 1:slavesCount
    master.CoexistenceVisualization.SlaveNumber = idx;
    master.CoexistenceVisualization.Action = 'Simulation Progress';
    viewModel(master.CoexistenceVisualization)
end

% Log the statistics of this example to
% |bleCoexistenceWithWLANSignalStatistics.mat| file
helperBLELogCoexistenceStats(master, slaves, ...
    'bleCoexistenceWithWLANSignalStatistics.mat');

% Restore the previous setting of random number generation
rng(sprev)