nrGNB

5G NR base station node

Since R2023a

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

Description

Use the nrGNB object to create and configure 5G new radio (NR) base station (gNB) nodes.

Creation

Syntax

gnb = nrGNB

gnb = nrGNB(PropertyName=Value)

Description

gnb = nrGNB creates a default gNB object.

gnb = nrGNB(PropertyName=Value) creates one or more similar gNB objects, and sets writable properties using one or more optional name-value arguments. For example, Position=[100 100 0; 5000 100 0],Name=["gNB1","gNB2"] creates two gNB objects, one with the name "gNB1" and the other named "gNB2", positioned at [100 100 0] and [5000 100 0], respectively. The number of rows in the Position argument defines the number of gNB objects created. If you create N nodes but supply M names, where M is greater than N, the nrGNB object uses only the first N names. If M is less than N, the object uses default names for the trailing (N-M) nodes.

Properties

Name — Name of gNB node

character vector | string scalar | string array | cell array of character vectors

Name of the gNB node, specified as a character vector, string scalar, vector of string array, or cell array of character vectors.

If you do not set the Name property, the nrGNB object sets a default name, NodeX, where X is the ID of the node.

To set the value of this property for multiple gNB nodes simultaneously, you must specify it at object creation. After object creation, you can set the value of this property for one gNB object at a time.

Data Types: char | string

Position — Node position in 3-D Cartesian coordinates

[0 0 0] (default) | three-element row vector | N-by-3 matrix

Node position in 3-D Cartesian coordinates, specified as a three-element numeric row vector or N-by-3 matrix. N is the number of nrGNB objects to create using the creation function. Each row specifies the position of the node in Cartesian x-, y-, and z- coordinates. Units are in meters.

To set the value of this property for multiple gNB nodes simultaneously, you must specify it at object creation. After object creation, you can set the value of this property for one gNB object at a time.

Data Types: double

NoiseFigure — Noise figure

6 (default) | nonnegative finite scalar

This property is read-only after object creation.

Noise figure, specified as a nonnegative finite scalar. Units are in dB.

Data Types: double

ReceiveGain — Receiver antenna gain

6 (default) | nonnegative finite scalar

This property is read-only after object creation.

Receiver antenna gain, specified as a nonnegative finite scalar. Units are in dB.

Data Types: double

NumTransmitAntennas — Number of transmit antennas

1 (default) | 2 | 4 | 8 | 16 | 32

This property is read-only after object creation.

Number of transmit antennas, specified as one of these options.

• 1

• 2

• 4

• 8

• 16

• 32

Data Types: double

NumReceiveAntennas — Number of receive antennas

1 (default) | 2 | 4 | 8 | 16 | 32

This property is read-only after object creation.

Number of receive antennas, specified as one of these options.

• 1

• 2

• 4

• 8

• 16

• 32

Data Types: double

TransmitPower — Transmit power

34 (default) | finite numeric scalar

This property is read-only after object creation.

Transmit power, specified as a finite numeric scalar. Units are in dBm. The maximum value of transmit power you can specify is 60 dBm.

Data Types: double

PHYAbstractionMethod — PHY abstraction method

"linkToSystemMapping" (default) | "none"

This property is read-only after object creation.

Physical (PHY) layer abstraction method, specified as one of these options. Note that all the gNB and user equipment (UE) nodes must use the same PHY abstraction method.

• "linkToSystemMapping" — Enable the link-to-system mapping-based abstracted PHY. The abstracted PHY models the link quality and performance to calculate the packet error rate (PER). Unlike full PHY, it does not involve waveform generation and decoding. For more information about the abstracted PHY, see Composition of NR Nodes.

• "none" — Enable full PHY processing. Full PHY processing involves waveform generation and decoding at the PHY layer.

Data Types: char | string

DuplexMode — Duplexing mode

"FDD" (default) | "TDD"

This property is read-only after object creation.

Duplexing mode, specified as one of these options.

• "FDD" — Frequency division duplex

• "TDD" — Time division duplex

Data Types: char | string

CarrierFrequency — Carrier frequency

2.6e9 (default) | real number

This property is read-only after object creation.

Carrier frequency, specified as a real number. Units are in Hz.

Note

The value of the CarrierFrequency property must be same for all interfering gNBs.

Data Types: double

ChannelBandwidth — Channel bandwidth

5e6 (default) | 10e6 | 15e6 | 20e6 | ...

This property is read-only after object creation.

Channel bandwidth, specified as one of these options. Units are in Hz.

• 5e6

• 10e6

• 15e6

• 20e6

• 30e6

• 35e6

• 40e6

• 45e6

• 50e6

• 60e6

• 70e6

• 80e6

• 90e6

• 100e6

• 200e6

• 400e6

In FDD mode, the downlink (DL) and uplink (UL) operations occur in separate bands of the specified size. In TDD mode, both DL and UL share a single band of the specified size.

Note

The value of the ChannelBandwidth property must be same for all interfering gNBs.

Data Types: double

SubcarrierSpacing — Subcarrier spacing used across the cell

15e3 (default) | 30e3 | 60e3 | 120e3

This property is read-only after object creation.

Subcarrier spacing (SCS) used across the cell, specified as one of these options. Units are in Hz.

• 15e3

• 30e3

• 60e3

• 120e3

Note

The value of the SubcarrierSpacing property must be same for all interfering gNBs.

Data Types: double

NumResourceBlocks — Number of resource blocks in channel bandwidth

25 (default) | integer in range [4, 273]

This property is read-only after object creation.

Number of resource blocks in the channel bandwidth, specified as an integer in the range [4,273].

In the FDD mode, the DL bandwidth and UL bandwidth each contain resource blocks equal to NumResourceBlocks. In the TDD mode, the DL and UL bandwidths share these resource blocks. If you do not specify this name-value argument, then the nrgNB object derives it automatically from the channel bandwidth and the subcarrier spacing. The default value, 25, corresponds to the default 5e6 Hz channel bandwidth and 15e3 Hz SCS. The minimum value, 4, is the minimum required transmission bandwidth for a sounding reference signal (SRS), as defined in TS 38.211, table 6.4.1.4.3-1 [3].

Data Types: double

DLULConfigTDD — DL and UL time division configuration for TDD mode

structure

This property is read-only after object creation.

DL and uplink UL time division configuration for TDD mode, specified as a structure. The structure contains these fields.

• DLULPeriodicity — DL-UL pattern periodicity in milliseconds. If you specify SCS as 15e3, 30e3, 60e3, or 120e3, then the default value of the DLULPeriodicity field is 5 milliseconds, 2.5 milliseconds, 1.25 milliseconds, or 0.625 milliseconds, respectively.

• NumDLSlots — Number of full DL slots at the start of the DL-UL pattern. The default value is 2.

• NumDLSymbols — Number of DL symbols after the full DL slots. The default value is 12.

• NumULSymbols — Number of full UL symbols at the end of the DL-UL pattern. The default value is 1.

• NumULSlots — Number of UL slots before the full UL slots. The default value is 2.

The nrGNB object sets the reference SCS for the DL-UL pattern to the value of SubcarrierSpacing. The configuration supports one S slot after the full DL slots and before the full UL slots. The S slot consists of NumDLSymbols at the start and NumULSymbols at the end. The object sets the guard period between DL and UL time to 14 - (NumDLSymbols + NumULSymbols). You can set NumULSymbols to 0 or 1. If you set NumULSymbols to 1, the gNB reserves the UL symbol for sounding reference signal (SRS).

Dependencies

To enable this property, set the DuplexMode property to "TDD".

SRSPeriodicityUE — SRS transmission periodicity of UE node

5 (default) | 8 | 10 | 16 | 20 | 32 | ...

Since R2025a

This property is read-only after object creation.

Sounding reference signal (SRS) transmission periodicity of a UE node, specified as 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, or 2560 slots. This value is identical for all connected UE nodes. This periodicity must also be an integer multiple of L, where L is the interval in slots at which the gNB reserves one symbol for the SRS resource across the entire bandwidth. The minimum value of L is 5. For FDD, the nrGNB object fixes the value of L at 5. For TDD, L is the minimum of these values: 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, or 2560 slots; the value of L is also a multiple of the DL-UL pattern length.

Data Types: double

NumHARQ — Number of HARQ processes

16 (default) | integer in range [1, 16]

This property is read-only after object creation.

Number of hybrid automatic repeat request (HARQ) processes used for each UE in the DL and UL directions, specified as an integer in the range [1, 16].

Data Types: double

ID — Node identifier

Read-only: positive integer

This property is read-only.

Node identifier, represented as a positive integer. This value specifies a unique identifier for the node in the simulation.

Note

If you create and store the gNB nodes in an uninitialized matrix, the node IDs that this property allocates to the nodes can be non-sequential because of the memory allocation to the object in the matrix. For more information about memory allocation, see How MATLAB Allocates Memory.

Data Types: double

ConnectedUEs — RNTIs of UEs

Read-only: vector of positive integers

This property is read-only.

Radio network temporary identifiers (RNTIs) of the UEs connected to a gNB node, represented as a vector of positive integers.

Data Types: double

UENodeIDs — IDs of the UE nodes connected to gNB

Read-only: vector of positive integers

Since R2024a

This property is read-only.

IDs of the UE nodes connected to the gNB node, represented as a vector of positive integers.

Data Types: double

UENodeNames — Names of the UE nodes connected to gNB

Read-only: array of strings

Since R2024a

This property is read-only.

Names of the UE nodes connected to the gNB node, represented as a vector of strings.

MCSTable — MCS used for DL and UL

Read-only: table

This property is read-only.

Modulation and coding scheme (MCS) used for DL and UL, represented as a table. For more information about this property, see TS 38.214, table 5.1.3.1-2 [1].

Object Functions

configureScheduler	Configure scheduler at gNB
configureULPowerControl	Configure uplink power control parameters
connectUE	Connect one or more UEs to gNB
addTrafficSource	Add data traffic source to 5G NR node
statistics	Statistics of gNB

Examples

Create gNB Nodes

Create two similar gNB nodes, one with the name "gNB1" and the other named "gNB2", positioned at [100 100 0] and [5000 100 0], respectively.

gNBs = nrGNB(Name=["gNB1" "gNB2"],Position=[100 100 0; 5000 100 0])

gNBs = 
  1×2 nrGNB array

gNBs(1)

ans = 
  nrGNB with properties:

                        Name: "gNB1"
                    Position: [100 100 0]

   Read-only properties:
                 NoiseFigure: 6
                 ReceiveGain: 6
               TransmitPower: 34
         NumTransmitAntennas: 1
          NumReceiveAntennas: 1
        PHYAbstractionMethod: "linkToSystemMapping"
                  DuplexMode: "FDD"
            CarrierFrequency: 2.6000e+09
            ChannelBandwidth: 5000000
           SubcarrierSpacing: 15000
           NumResourceBlocks: 25
                     NumHARQ: 16
    ULPowerControlParameters: [1×1 struct]
            SRSPeriodicityUE: 5
                          ID: 5

   Constant properties:
                    MCSTable: [28×4 table]

gNBs(2)

ans = 
  nrGNB with properties:

                        Name: "gNB2"
                    Position: [5000 100 0]

   Read-only properties:
                 NoiseFigure: 6
                 ReceiveGain: 6
               TransmitPower: 34
         NumTransmitAntennas: 1
          NumReceiveAntennas: 1
        PHYAbstractionMethod: "linkToSystemMapping"
                  DuplexMode: "FDD"
            CarrierFrequency: 2.6000e+09
            ChannelBandwidth: 5000000
           SubcarrierSpacing: 15000
           NumResourceBlocks: 25
                     NumHARQ: 16
    ULPowerControlParameters: [1×1 struct]
            SRSPeriodicityUE: 5
                          ID: 6

   Constant properties:
                    MCSTable: [28×4 table]

Establish Connection Between gNB and UE

Create a default gNB node.

gnb = nrGNB

gnb = 
  nrGNB with properties:

                        Name: "Node24"
                    Position: [0 0 0]

   Read-only properties:
                 NoiseFigure: 6
                 ReceiveGain: 6
               TransmitPower: 34
         NumTransmitAntennas: 1
          NumReceiveAntennas: 1
        PHYAbstractionMethod: "linkToSystemMapping"
                  DuplexMode: "FDD"
            CarrierFrequency: 2.6000e+09
            ChannelBandwidth: 5000000
           SubcarrierSpacing: 15000
           NumResourceBlocks: 25
                     NumHARQ: 16
    ULPowerControlParameters: [1×1 struct]
            SRSPeriodicityUE: 5
                          ID: 24

   Constant properties:
                    MCSTable: [28×4 table]

Create a default UE node.

ue = nrUE

ue = 
  nrUE with properties:

                    Name: "Node25"
                Position: [0 0 0]

   Read-only properties:
             NoiseFigure: 6
             ReceiveGain: 0
           TransmitPower: 23
     NumTransmitAntennas: 1
      NumReceiveAntennas: 1
    PHYAbstractionMethod: "linkToSystemMapping"
         ConnectionState: "Idle"
                      ID: 25

Establish a connection between the UE node and the gNB node.

connectUE(gnb,ue)

Create, Configure, and Simulate 5G Network

Initialize wireless network simulator.

networkSimulator = wirelessNetworkSimulator.init;

Create a gNB node with these specifications.

• Duplex mode — Time division duplex

• Channel bandwidth — 20 MHz

• Subcarrier spacing — 30 KHz

gnb = nrGNB(ChannelBandwidth=20e6,DuplexMode="TDD",SubcarrierSpacing=30e3);

Create a UE node with a transmit power of 20 dBm.

ue = nrUE(TransmitPower=20);

Configure these uplink power control parameters at the gNB node.

• Nominal transmit power of UE per resource block — 7 dBm

• Fractional power control multiplier— 2

configureULPowerControl(gnb,PoPUSCH=7,Alpha=0.4)

Add a random way point mobility model to the UE node.

addMobility(ue,BoundaryShape="rectangle")

Establish a connection between the UE and gNB nodes.

connectUE(gnb,ue)

Create a voice over Internet protocol (VoIP) application traffic pattern object.

traffic = networkTrafficVoIP(GeneratePacket=true);

Add the data traffic source to the gNB node. Set the destination node as the UE node.

addTrafficSource(gnb,traffic,DestinationNode=ue)

Add the gNB node to the wireless network simulator.

addNodes(networkSimulator,gnb)

Add the UE node to the wireless network simulator.

addNodes(networkSimulator,ue)

Specify the simulation time, in seconds.

simulationTime = 0.3;

Run the simulation for the specified simulation time.

run(networkSimulator,simulationTime)

Obtain the statistics for the gNB and UE nodes.

gnbStats = statistics(gnb);
ueStats = statistics(ue);

References

[1] 3GPP TS 38.104. “NR; Base Station (BS) radio transmission and reception.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[2] 3GPP TS 38.214. “NR; Physical layer procedures for data.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[3] 3GPP TS 38.211. “NR; Physical channels and modulation.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[4] 3GPP TS 38.321. “NR; Medium Access Control (MAC) protocol specification.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[5] 3GPP TS 38.322. “NR; Radio Link Control (RLC) protocol specification.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

Version History

Introduced in R2023a

R2025a: Includes support for specifying SRS transmission periodicity of UE nodes

The nrGNB object now allows you to specify the SRS transmission periodicity of a UE node through the SRSPeriodicityUE name-value argument.

R2024a: Includes support for accessing IDs and names of the UE nodes connected to gNB node

The nrGNB object now allows you to access the IDs and names of the UE nodes connected to a gNB node through the UENodeIDs and UENodeNames properties, respectively.

R2023b: Includes support for configuring UL power control parameters and selecting PHY layer processing method

The nrGNB object now supports these functionalities.

• Configure UL power control parameters through the configureULPowerControl object function.

• Select a PHY layer processing method through the PHYAbstractionMethod property.