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configureScheduler

Configure scheduler at gNB

Since R2023a

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    Download Required: To use configureScheduler, first download the Communications Toolbox Wireless Network Simulation Library add-on.

    Syntax

    configureScheduler(gnb,Name=Value)

    Description

    example

    configureScheduler(gnb,Name=Value) configures a scheduler at a 5G new radio (NR) base station (gNB) node. The function sets the scheduling parameters using one or more optional name-value arguments. For example, ResourceAllocationType=0 sets the resource allocation type to 0. You can configure a scheduler at multiple gNB nodes in a single configureScheduler function call. In this case, all the nodes use the same scheduling parameter values specified in the name-value arguments.

    Examples

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    This example uses:

    Open Live Script

    Initialize the wireless network simulator.

    networkSimulator = wirelessNetworkSimulator.init;

    Create a default gNB node.

    gnb = nrGNB;

    Create two UE nodes, specifying their positions.

    ue = nrUE(Position=[100 100 0; 5000 100 0]); % In Cartesian x, y, and z coordinates.

    Configure a scheduler at the gNB with the maximum number of users per transmission time interval (TTI) as 3.

    configureScheduler(gnb,MaxNumUsersPerTTI=3)

    Connect the UE nodes to the gNB node.

    connectUE(gnb,ue)

    Create voice over Internet protocol (VoIP) application traffic pattern objects to generate VoIP application traffic patterns between the gNB and UE nodes.

    traffic1 = networkTrafficVoIP(ExponentialMean=5,GeneratePacket=true);
traffic2 = networkTrafficVoIP(ExponentialMean=125,GeneratePacket=true);

    Add a data traffic source from the gNB node to the UE nodes.

    addTrafficSource(gnb,traffic1,DestinationNode=ue(1))
addTrafficSource(gnb,traffic2,DestinationNode=ue(2))

    Add the nodes to the network simulator.

    addNodes(networkSimulator,gnb)
addNodes(networkSimulator,ue)

    Set the simulation time, in seconds.

    simulationTime = 0.3;

    Run the simulation for the specified simulation time.

    run(networkSimulator,simulationTime)

    Obtain statistics for the gNB and UE nodes.

    gnbStats = statistics(gnb);
ue1Stats = statistics(ue(1));
ue2Stats = statistics(ue(2));

    Input Arguments

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    gNB node, specified as an nrGNB object or an array of nrGNB 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: configureScheduler(gnb,ResourceAllocationType=0) sets the resource allocation type to 0

    Scheduler strategy, specified as one of these options.

    • "RoundRobin" — Enable the round-robin scheduler. This scheduler provides equal scheduling opportunities to all the UE nodes.

    • "BestCQI" — Enable the best channel quality indicator (CQI) scheduler. This scheduler gives priority to the UE node with the best CQI.

    • "ProportionalFair" — Enable the proportional-fair scheduler. This scheduler is a compromise between the round-robin and best CQI schedulers.

    Data Types: char | string

    Time constant of an exponential moving average, specified as a positive integer, in number of slots. The proportional-fair scheduler uses this time constant to calculate the average data rate.

    Dependencies

    To enable this name-value argument, specify the Scheduler argument as "ProportionalFair".

    Data Types: double

    Resource allocation type, specified as 1 (resource allocation type 1) or 0 (resource allocation type 0).

    Data Types: double

    Maximum number of users per transmission time interval (TTI), specified as a positive integer.

    Data Types: double

    Modulation and coding scheme (MCS) index for downlink (DL), specified as an integer in the range [0, 27]. The MCS index corresponds to a row in TS 38.214, table 5.1.3.1-2 [1]. The gNB node stores the MCS table as the static property MCSTable. The default value of [] indicates for the gNB to select the MCS based on the CSI-RS measurement report.

    Data Types: double

    Modulation and coding scheme (MCS) index for uplink ( UL), specified as an integer in the range [0, 27]. The MCS index corresponds to a row in TS 38.214, table 5.1.3.1-2. The gNB node stores the MCS table as static property MCSTable. The default value of [] indicates for the gNB to select the MCS based on the sounding reference signal (SRS) measurements.

    Data Types: double

    Configuration of DL multi-user multiple-input and multiple-output (MU-MIMO), specified as a structure. The structure must contain these fields.

    • MaxNumUsersPaired — The maximum number of users that the scheduler can pair for a MU-MIMO transmission, specified as integer in the range [2, 4]. The default value is 2

    • MinNumRBs — The minimum number of resource blocks (RBs) the scheduler must allocate to a UE for considering the UE as an MU-MIMO candidate, specified as a positive integer. The default value is 6.

    • MinCQI — The minimum channel quality indicator (CQI) required for considering a UE as an MU-MIMO candidate, specified as an integer in the range [1, 15]. The default value is 7. For more information about the CQI table, see TS 38.214 Table 5.2.2.1-2 [1].

    • SemiOrthogonalityFactor — Inter-user interference (IUI) orthogonality factor, specified as a numeric scalar in the range [0, 1]. The scheduler uses this value to decide whether to pair up the UE nodes for MU-MIMO. SemiOrthogonalityFactor values of 0 and 1 indicate nonorthogonality and orthogonality between the UE nodes, respectively. The default value of SemiOrthogonalityFactor is 0.75.

    References

    [1] 3GPP TS 38.321. “NR; Medium Access Control (MAC) protocol specification.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

    Version History

    Introduced in R2023a

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    See Also

    Objects

    Functions

    Topics