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addMobility

Add random waypoint mobility model to Bluetooth LE node

Since R2023b

    Download Required: To use addMobility, first download the Communications Toolbox Wireless Network Simulation Library add-on. For more information, see Get and Manage Add-Ons.

    Description

    addMobility(blenode) adds a random waypoint mobility model to Bluetooth® low energy (LE) nodes, blenode. In the random waypoint model, a wireless node pauses for some duration at a location before moving towards its next random destination (waypoint) with a random speed. The node repeats this process at each waypoint.

    example

    addMobility(blenode,Name=Value) sets the random waypoint mobility configuration parameters using one or more optional name-value arguments. For example, PauseDuration=0.02 sets the pause duration of a Bluetooth LE node to 0.02 seconds. If you add random waypoint mobility models to multiple wireless nodes in a single addMobility function call, all the nodes use the mobility parameter values specified by the name-value arguments.

    Examples

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    This example shows you how to simulate a Bluetooth® low energy (LE) network with a custom channel by using Bluetooth® Toolbox and Communications Toolbox™ Wireless Network Simulation Library.

    Using this example, you can:

    1. Create and configure a Bluetooth LE piconet with Central and Peripheral nodes.

    2. Create and configure a link layer (LL) connection between Central and Peripheral nodes.

    3. Add application traffic from the Central to Peripheral nodes.

    4. Create a custom channel, and plug it into the wireless network simulator.

    5. Simulate Bluetooth LE network and retrieve the statistics of the Central and Peripheral nodes.

    Check if the Communications Toolbox™ Wireless Network Simulation Library support package is installed. If the support package is not installed, MATLAB® returns an error with a link to download and install the support package.

    wirelessnetworkSupportPackageCheck

    Create a wireless network simulator.

    networkSimulator = wirelessNetworkSimulator.init;

    Create a Bluetooth LE node, specifying the role as "central". Specify the name and position of the node.

    centralNode = bluetoothLENode("central");
    centralNode.Name = "CentralNode";
    centralNode.Position = [0 0 0];                 % In x-, y-, and z-coordinates in meters

    Create a Bluetooth LE node, specifying the role as "peripheral". Specify the name and position of the node.

    peripheralNode = bluetoothLENode("peripheral");
    peripheralNode.Name = "PeripheralNode";
    peripheralNode.Position = [10 0 0]              % In x-, y-, and z-coordinates in meters
    peripheralNode = 
      bluetoothLENode with properties:
    
             TransmitterPower: 20
              TransmitterGain: 0
                ReceiverRange: 100
                 ReceiverGain: 0
          ReceiverSensitivity: -100
                  NoiseFigure: 0
         InterferenceModeling: "overlapping-adjacent-channel"
        MaxInterferenceOffset: 100000000
         InterferenceFidelity: 0
                         Name: "PeripheralNode"
                     Position: [10 0 0]
    
       Read-only properties:
                         Role: "peripheral"
             ConnectionConfig: [1x1 bluetoothLEConnectionConfig]
                    CISConfig: [1x1 bluetoothLECISConfig]
               TransmitBuffer: [1x1 struct]
                           ID: 2
    
    

    Add a random waypoint mobility model to the Bluetooth peripheral node. Set the shape of the node's mobility area to "circle".

    addMobility(peripheralNode,BoundaryShape="circle");

    Create a default Bluetooth LE configuration object to share the LL connection between the Central and Peripheral nodes.

    cfgConnection = bluetoothLEConnectionConfig;

    Specify the connection interval and connection offset. Throughout the simulation, the object establishes LL connection events for the duration of each connection interval. The connection offset is from the beginning of the connection interval.

    cfgConnection.ConnectionInterval = 0.01; % In seconds
    cfgConnection.ConnectionOffset = 0;      % In seconds

    Specify the active communication period after the connection event is established between the Central and Peripheral nodes.

    cfgConnection.ActivePeriod = 0.01 % In seconds
    cfgConnection = 
      bluetoothLEConnectionConfig with properties:
    
        ConnectionInterval: 0.0100
             AccessAddress: "5DA44270"
              UsedChannels: [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36]
                 Algorithm: 1
              HopIncrement: 5
         CRCInitialization: "012345"
        SupervisionTimeout: 1
                   PHYMode: "LE1M"
             InstantOffset: 6
          ConnectionOffset: 0
              ActivePeriod: 0.0100
    
    

    Configure the connection between Central and Peripheral nodes by using the configureConnection object function of the bluetoothLEConnectionConfig object.

    configureConnection(cfgConnection,centralNode,peripheralNode);

    Create a networkTrafficOnOff object to generate an On-Off application traffic pattern. Specify the data rate in kb/s and the packet size in bytes. Enable packet generation to generate an application packet with a payload.

    traffic = networkTrafficOnOff(DataRate=100, ...
                                  PacketSize=10, ...
                                  GeneratePacket=true);

    Add application traffic from the Central to the Peripheral node by using the addTrafficSource object function.

    addTrafficSource(centralNode,traffic,"DestinationNode",peripheralNode.Name);

    Create a Bluetooth LE network consisting of a Central and a Peripheral node.

    nodes = {centralNode peripheralNode};

    Add the Central and Peripheral nodes to the wireless network simulator.

    addNodes(networkSimulator,nodes)

    Add the custom channel to the wireless network simulator.

    addChannelModel(networkSimulator,@addImpairment);

    Set the simulation time in seconds and run the simulation.

    simulationTime = 0.5;
    run(networkSimulator,simulationTime)

    Retrieve application, link layer (LL), and physical layer (PHY) statistics corresponding to the broadcaster and receiver nodes. For more information about the statistics, see Bluetooth LE Node Statistics.

    centralStats = statistics(centralNode)
    centralStats = struct with fields:
        Name: "CentralNode"
          ID: 1
         App: [1x1 struct]
          LL: [1x1 struct]
         PHY: [1x1 struct]
    
    
    peripheralStats = statistics(peripheralNode)
    peripheralStats = struct with fields:
        Name: "PeripheralNode"
          ID: 2
         App: [1x1 struct]
          LL: [1x1 struct]
         PHY: [1x1 struct]
    
    

    Follow these steps to create a custom channel that models Bluetooth path loss for an industrial scenario.

    • Create a custom function with this syntax: rxData = customFcnName(rxInfo,txData). The rxInfo input specifies the receiver node information as a structure, and the txData input specifies the transmitted packets as a structure. The simulator automatically passes information about the receiver node and the packets transmitted by a transmitter node as inputs to the custom function. For more information about creating custom channel, see the addChannelModel object function.

    • Use the bluetoothPathLossConfig object to set path loss configuration parameters for an industrial scenario.

    • Calculate path loss between the Central and Peripheral nodes using the bluetoothPathLoss function. Specify the transmitter and receiver positions.

    • Apply path loss to the transmitted packets.

    function rxData = addImpairment(rxInfo,txData)
    
        pathlossCfg = bluetoothPathLossConfig(Environment="Industrial");
    
        % Apply path loss and update output signal
        rxData = txData;
    
        % Calculate the distance between transmitter and receiver in meters
        distance = norm(rxData.TransmitterPosition - rxInfo.Position);
        pathloss = bluetoothPathLoss(distance,pathlossCfg);
        rxData.Power = rxData.Power-pathloss;                           % In dBm
        scale = 10.^(-pathloss/20);
        [numSamples,~] = size(rxData.Data);
        rxData.Data(1:numSamples,:) = rxData.Data(1:numSamples,:)*scale;
    end

    Input Arguments

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    Bluetooth LE node, specified as a bluetoothLENode object or an array of bluetoothLENode objects.

    Name-Value Arguments

    Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

    Example: addMobility(blenode,PauseDuration=0.02) sets the pause duration for a Bluetooth LE node, after it reaches a target waypoint, to 0.02 seconds.

    Speed range, specified as a two-element numeric vector. The function sets the speed of the Bluetooth LE node according to a continuous uniform distribution based on this range. The first element of the vector specifies the minimum speed of the node, while the second specifies the maximum speed, in meters per second.

    Data Types: double

    Pause duration of the Bluetooth LE node after reaching a target waypoint, specified as a nonnegative scalar. Units are in seconds.

    Data Types: double

    Shape of the node mobility area, specified as "rectangle" or "circle".

    Data Types: char | string

    Center coordinates and dimensions of the mobility area, specified as a three-element or four-element numeric vector, depending on the value of the BoundaryShape argument.

    • "rectangle" — Specify a four-element numeric vector of the form [xcenter ycenter length width]. The default value is [xcurrent ycurrent 10 10], where the first two elements specify the xy-coordinates of current node position.

    • "circle" — Specify a three-element numeric vector of the form [xcenter ycenter radious]. The default value is [xcurrent ycurrent 10], where the first two elements specify the xy-coordinates of current node position.

    Data Types: double

    Version History

    Introduced in R2023b