nrWavegenSRSConfig

SRS configuration parameters for 5G waveform generation

Since R2021a

Description

The nrWavegenSRSConfig object sets sounding reference signal (SRS) configuration parameters, as defined in TS 38.211 Section 6.4.1.4 [1]. Use this object to set the SRS property of the nrULCarrierConfig object when configuring 5G uplink waveform generation.

The default nrWavegenSRSConfig object specifies a single-port, single-symbol, narrowband SRS configuration without frequency hopping (BHop ≥ BSRS) and places the SRS at the end of the slot.

Creation

Syntax

srs = nrWavegenSRSConfig

srs = nrWavegenSRSConfig(PropertyName=Value)

Description

srs = nrWavegenSRSConfig creates a default SRS configuration object for 5G waveform generation.

srs = nrWavegenSRSConfig(PropertyName=Value) sets writable properties using one or more name-value arguments. For example, NumSRSPorts=2,NumSRSSymbols=4 specifies a two-port SRS transmission of 4 OFDM symbols.

Properties

Enable — Enable SRS

1 or true (default) | 0 or false

Enable the SRS in 5G waveform generation, specified as one of these values.

• 1 (true) — Enable the SRS.

• 0 (false) — Disable the SRS.

Data Types: double | logical

Label — Name of SRS configuration

'SRS1' (default) | character array | string scalar

Name of the SRS configuration, specified as a character array or string scalar. Use this property to set a description to the SRS configuration.

Data Types: char | string

Power — Power scaling of SRS in dB

0 (default) | real-valued scalar | real-valued vector (since R2024b)

Power scaling of the SRS in dB, specified as a real-valued scalar or real-valued vector of length equal to the number of allocated transmissions in a period configured by the SlotAllocation property. Use this property to scale the power of the SRS in the generated 5G waveform.

Data Types: double

BandwidthPartID — ID of BWP

1 (default) | nonnegative integer

ID of the bandwidth part (BWP) containing the configured SRS, specified as a nonnegative integer. Use this property to associate this SRS configuration with one of the BWP configurations specified by the BandwidthParts property of the nrULCarrierConfig object.

Data Types: double

NumSRSPorts — Number of SRS antenna ports

1 (default) | 2 | 4 | 8 (since R2024a)

Number of SRS antenna ports, specified as 1, 2, 4, or 8.

Data Types: double

SymbolStart — 0-based index of first OFDM symbol

13 (default) | integer from 0 to 13

0-based index of the first OFDM symbol in the SRS within a slot, specified as one of these options:

• Integer from 0 to 13 — Use this option for normal cyclic prefix.

• Integer from 0 to 11 — Use this option for extended cyclic prefix.

For the SRS symbols and index generation, set the cyclic prefix of the carrier by using the CyclicPrefix property of the BWP configuration object specified by the BandwidthPartID property.

Data Types: double

NumSRSSymbols — Number of OFDM symbols allocated to the SRS

1 (default) | 2 | 4 | 8 | 10 | 12 | 14

Number of OFDM symbols allocated to the SRS in slot, specified as 1, 2, 4, 8, 10, 12, or 14. Property values 10 and 14 are only valid when you set the SRSPositioning property to 0 (false).

When you set the SRSPositioning property to 1 (true), for valid configurations of this property and the KTC property, see TS 38.211 Table 6.4.1.4.3-2. Alternatively, to display this table, type nrSRSConfig.SubcarrierOffsetTable at the command line.

Data Types: double

SlotAllocation — Slot allocation in SRS period

[0:9] (default) | nonnegative integer | row vector of nonnegative integers

Slot allocation in an SRS period, specified as a nonnegative integer or a row vector of nonnegative integers. This property specifies the slot positions of the SRS by using 0-based indexing and values that are less than the value of the Period property. The object ignores slot allocation values that are greater than the period. Each element of the vector corresponds to an SRS resource.

Data Types: char

Period — SRS allocation period in slots

10 (default) | nonnegative integer | []

SRS allocation period in slots, specified as a nonnegative integer or []. An empty period indicates aperiodic SRS resource type (no repetition), as defined in TS 38.211 Section 6.4.1.4.3.

Data Types: double

FrequencyStart — Frequency-domain offset

0 (default) | integer from 0 to 271

Frequency-domain offset of the SRS, in terms of a physical resource block (PRB) index relative to the carrier, specified as an integer from 0 to 271. FrequencyStart is analogous to parameter $$n_{{}_{shift}}$$ from TS 38.211 Section 6.4.1.4.3.

This property, the additional circular frequency-domain offset property NRRC, and the bandwidth configuration parameters in TS 38.211 Table 6.4.1.4.3-1 determine the actual frequency-domain location of the SRS. For more information, see NR SRS Configuration.

Data Types: double

NRRC — Additional circular frequency-domain offset

0 (default) | integer from 0 to 67

Additional circular frequency-domain offset of the SRS, as a multiple of 4 PRBs, specified as an integer from 0 to 67.

This property, the frequency domain offset property FrequencyStart, and the bandwidth configuration parameters in TS 38.211 Table 6.4.1.4.3-1 determine the actual frequency-domain location of the SRS. For more information, see NR SRS Configuration.

Data Types: double

CSRS — Row index of bandwidth configuration table

0 (default) | integer from 0 to 63

Row index of the bandwidth configuration table from TS 38.211 Table 6.4.1.4.3-1, specified as an integer from 0 to 63. Use this property with the BSRS property to control the bandwidth allocated to the SRS and the frequency hopping pattern. Increasing the CSRS value increases the SRS bandwidth. The default value of 0 results in a bandwidth of 4 PRBs.

Data Types: double

BSRS — Column index of bandwidth configuration table

0 (default) | integer from 0 to 3

Column index of the bandwidth configuration table from TS 38.211 Table 6.4.1.4.3-1, specified as an integer from 0 to 3. Use this property with the CSRS property to control the bandwidth allocated to the SRS and the frequency hopping pattern. Increasing the BSRS value decreases the SRS bandwidth.

Data Types: double

BHop — Frequency hopping index

0 (default) | integer from 0 to 3

Frequency hopping index, specified as an integer from 0 to 3. Setting this property to a value greater than or equal to the column index of the bandwidth configuration table property, BSRS, disables frequency hopping. Increasing the BHop value decreases the hopping bandwidth.

Data Types: double

Repetition — Repetition factor of OFDM symbols

1 (default) | 2 | 4 | 5 | 6 | 7 | 8 | 10 | 12 | 14

Repetition factor of OFDM symbols, specified as 1, 2, 4, 5, 6, 7, 8, 10, 12, or 14.

• When frequency hopping is enabled, Repetition specifies the number of consecutive OFDM symbols in a slot occupied by the SRS in the same frequency resource. Set Repetition such that Repetition ≤ NumSRSSymbols.

• When frequency hopping is disabled, this property is ignored.

Data Types: double

KTC — Transmission comb number

2 (default) | 4 | 8

Transmission comb number, in subcarriers, specified as 2, 4, or 8. This property specifies the minimum frequency separation between two subcarriers that allocate SRS.

When you set the SRSPositioning property to 1 (true), for valid configurations of this property and the NumSRSSymbols property, see TS 38.211 Table 6.4.1.4.3-2. Alternatively, to display this table, type nrSRSConfig.SubcarrierOffsetTable at the command line.

Data Types: double

KBarTC — Transmission comb offset

0 (default) | integer from 0 to (KTC – 1)

Transmission comb offset, in subcarriers, specified as an integer from 0 to (KTC – 1). This property specifies a frequency offset within the comb.

Data Types: double

FrequencyScalingFactor — Frequency scaling factor

1 (default) | 2 | 4

Frequency scaling factor, specified as 1, 2, or 4. Use this property to reduce the SRS transmission bandwidth for partial frequency sounding. This property corresponds to the parameter P_F in Release 17 of TS 38.211 Section 6.4.1.4.3. The default value 1 disables frequency scaling.

Data Types: double

StartRBIndex — Partial frequency sounding block index

0 (default) | nonnegative integer

Partial frequency sounding block index, specified as a nonnegative integer in the range [0, FrequencyScalingFactor–1].

Use this property to control the SRS frequency position when you set the FrequencyScalingFactor property to 2 or 4.

Data Types: double

EnableStartRBHopping — Enable frequency hopping of first RB

0 or false (default) | 1 or true

Enable frequency hopping of the first RB in the SRS transmission for partial frequency sounding, specified as one of these logical values.

• 0 (false) — Disable frequency hopping of the first RB.

• 1 (true) — Enable frequency hopping of the first RB.

Use this property to control the frequency hopping of the first RB when you set the FrequencyScalingFactor property to 2 or 4.

Data Types: logical | double

AntennaMapping — Mapping of signal ports to physical antennas

[] (default) | vector of unique positive integers

Since R2025a

Mapping of signal ports to physical antennas, specified as one of these values:

• [] — The instance specified by this nrWavegenSRSConfig object is automatically mapped in the generated waveform starting from the first column.

• Vector of N unique positive integers — The vector elements indicate where the instance specified by this nrWavegenSRSConfig object is mapped in the generated waveform.

  • If PrecodingMatrix is empty ([]), N = NumSRSPorts.

  • If PrecodingMatrix is nonempty, N and the number of rows in the precoding matrix must be equal.

Data Types: double

PrecodingMatrix — Precoding matrix

[] (default) | numeric matrix

Since R2025a

Precoding matrix, specified as one of these options:

• [] — Precoding is not applied to the generated waveform.

• M-by-NumSRSPorts numeric matrix — Precoding is applied to the generated waveform using the specified matrix.

  • If AntennaMapping is empty ([]), M is any positive integer.

  • If AntennaMapping is nonempty, M and the number of unique elements specified in the antenna mapping must be equal.

Note

Setting this property to a nonempty value can affect the power applied to the instance specified by this nrWavegenSRSConfig object in the generated waveform.

Data Types: double

CyclicShift — Cyclic shift offset

0 (default) | integer from 0 to 11

Cyclic shift offset, specified as an integer from 0 to 11. This property determines the cyclic shift applied to the SRS sequence for each antenna port. This property corresponds to parameter $$n_{SRS}^{cs}$$ in TS 38.211 Section 6.4.1.4.2.

Set the cyclic shift offset in relation to the transmission comb property, KTC:

• If you set KTC to 2, set CyclicShift to an integer from 0 to 7.

• If you set KTC to 4, set CyclicShift to an integer from 0 to 11.

• If you set KTC to 8, set CyclicShift to an integer from 0 to 5.

For multiport SRS transmissions, consecutive cyclic shift numbers are used for each port, modulo 6, 8, or 12, depending on the KTC property.

Data Types: double

GroupSeqHopping — Type of SRS symbol hopping

'neither' (default) | 'groupHopping' | 'sequenceHopping'

Type of SRS symbol hopping, specified as 'neither', 'groupHopping', or 'sequenceHopping'. When either group or sequence hopping is enabled, the group or sequence hopping numbers per OFDM symbol in the SRS transmission are based on a pseudo-random binary sequence (PRBS). Set the scrambling identity for the PRBS by using the NSRSID property.

Data Types: char | string

NSRSID — SRS scrambling identity

0 (default) | integer from 0 to 65,535

SRS scrambling identity, specified as an integer from 0 to 65,535.

• When you set the GroupSeqHopping property to 'neither', this property determines the group number.

• When you set the GroupSeqHopping property to 'groupHopping' or 'sequenceHopping', this property initializes the PRBS.

Data Types: double

SRSPositioning — SRS for user positioning

0 or false (default) | 1 or true

SRS for user positioning, as defined in Release 16 of TS 38.211 Section 6.4.1.4, specified as one of these values.

• 0 (false) — Disable SRS for user positioning. This option corresponds to the higher-layer parameter SRS-Resource.

• 1 (true) — Enable SRS for user positioning. This option corresponds to the higher-layer parameter SRS-PosResource-r16.

This property affects the valid range of the NumSRSSymbols and KTC properties.

Data Types: logical | double

EnableEightPortTDM — Eight-port TDM

0 or false (default) | 1 or true

Since R2024a

Eight-port time division multiplexing (TDM), specified as one of these logical values:

• 0 (false) — Disable eight-port TDM in the SRS transmission.

• 1 (true) — Enable eight-port TDM in the SRS transmission. This option corresponds to a configuration in which the higher-layer parameter nrofSRS-Ports-n8 is set to ports8tdm.

Dependencies

To enable this property, set the NumSRSPorts property to 8.

Data Types: logical | double

CyclicShiftHopping — Cyclic shift hopping

0 or false (default) | 1 or true

Since R2024a

Cyclic shift hopping, specified as one of these logical values:

• 0 (false) — Disable cyclic shift hopping in the SRS transmission.

• 1 (true) — Enable cyclic shift hopping in the SRS transmission. This option corresponds to a configuration in which the higher-layer parameter cyclicShiftHopping is present.

Data Types: logical | double

CyclicShiftHoppingID — Cyclic shift hopping ID

0 (default) | nonnegative integer

Since R2024a

Cyclic shift hopping ID, specified as a nonnegative integer. This property initializes the pseudorandom binary sequence (PRBS) that defines the cyclic shift hopping pattern.

Dependencies

To enable this property, set the CyclicShiftHopping property to true.

Data Types: double

CyclicShiftHoppingSubset — Cyclic shift hopping subset

[] (default) | vector of nonnegative integers

Since R2024a

Cyclic shift hopping subset, specified as a vector of nonnegative integers. This property corresponds to the higher-layer parameter cyclicShiftHoppingSubset and specifies the set of cyclic shifts for hopping in the SRS transmission. The PRBS that you initialize with the CyclicShiftHoppingID property determines the order of the cyclic shifts in the hopping pattern. The default value, [], implies that the object automatically selects the {0, 1, ..., K⨯NCSmax – 1} set. NCSmax is the maximum number of cyclic shifts, as defined in TS 38.211 Table 6.4.1.4.2-1. K = 1 by default. To enable finer granularity, set the HoppingFinerGranularity property to true, in which case K = 2.

Dependencies

To enable this property, set the CyclicShiftHopping property to true.

Data Types: double

HoppingFinerGranularity — Finer granularity for cyclic shift hopping

0 or false (default) | 1 or true

Since R2024a

Finer granularity for cyclic shift hopping, specified as one of these logical values:

• 0 (false) — Disable finer granularity for cyclic shift hopping in the SRS transmission.

• 1 (true) — Enable finer granularity for cyclic shift hopping in the SRS transmission. This option corresponds to a configuration in which the higher-layer parameter hoppingFinerGranularity is present.

This property determines the value of the K parameter in the default cyclic shift hopping subset that the object automatically selects when you set the CyclicShiftHoppingSubset property to [].

Dependencies

To enable this property, set the CyclicShiftHopping property to true.

Data Types: double | logical

CombOffsetHopping — Comb offset hopping

0 or false (default) | 1 or true

Since R2024a

Comb offset hopping, specified as one of these logical values:

• 0 (false) — Disable comb offset hopping in the SRS transmission.

• 1 (true) — Enable comb offset hopping in the SRS transmission. This option corresponds to a configuration in which the higher-layer parameter combOffsetHopping is present.

Data Types: double | logical

CombOffsetHoppingID — Comb offset hopping ID

0 (default) | nonnegative integer

Since R2024a

Comb offset hopping ID, specified as a nonnegative integer. This property initializes the PRBS that defines the comb offset hopping pattern.

Dependencies

To enable this property, set the CombOffsetHopping property to true.

Data Types: double

CombOffsetHoppingSubset — Comb offset hopping subset

[] (default) | matrix of nonnegative integers

Since R2024a

Comb offset hopping subset, specified as a matrix of nonnegative integers. This property corresponds to the higher-layer parameter combOffsetHoppingSubset and specifies the set of comb offsets for hopping in the SRS transmission. The PRBS that you initialize with the CombOffsetHoppingID property determines the order of the comb offsets in the hopping pattern. The default value, [], implies that the object automatically selects the {0,1,...,KTC – 1} set, which depends on the transmission comb number property value.

Dependencies

To enable this property, set the CombOffsetHopping property to true.

Data Types: double

HoppingWithRepetition — Comb offset hopping with repetition

0 or false (default) | 1 or true

Since R2024a

Comb offset hopping with repetition, specified as one of these logical values:

• 0 (false) — Disable time repetition for the comb offset hopping in the SRS transmission.

• 1 (true) — Enable time repetition for the comb offset hopping in the SRS transmission. The repetition factor of the OFDM symbols, specified by the Repetition property, determines the minimum number of symbols for which the comb offset remains constant. This option corresponds to a configuration in which the higher-layer parameter hoppingWithRepetition is present.

Dependencies

To enable this property, set the CombOffsetHopping property to true.

Data Types: double | logical

Examples

Configure SRS for 5G Uplink Waveform Generation

Create two SCS carrier configuration objects with mixed numerologies and custom numbers of resource blocks.

carriers = {
    nrSCSCarrierConfig('SubcarrierSpacing',15,'NStartGrid',10,'NSizeGrid',100), ...
    nrSCSCarrierConfig('SubcarrierSpacing',30,'NStartGrid',0,'NSizeGrid',70)};

Create two BWP configuration objects, one for each of the SCS carriers.

bwp = {
    nrWavegenBWPConfig('BandwidthPartID',1,'SubcarrierSpacing',15,'NStartBWP',10,'NSizeBWP',80), ...
    nrWavegenBWPConfig('BandwidthPartID',2,'SubcarrierSpacing',30,'NStartBWP',0,'NSizeBWP',60)};

Create two SRS configuration objects, one for each of the carriers, with the specified properties. In the first SRS configuration, frequency hopping is enabled. In the second SRS configuration, frequency hopping is disabled.

srs = {
    nrWavegenSRSConfig('BandwidthPartID',1,'NumSRSPorts',2,'NumSRSSymbols',4,'SymbolStart',8,'CSRS',14,'BSRS',1), ... 
    nrWavegenSRSConfig('BandwidthPartID',2,'FrequencyStart',4)};

Create a PUSCH configuration object such that the PUSCH does not overlap with the previously configured SRS in the generated waveform.

pusch = {
    nrWavegenPUSCHConfig('BandwidthPartID',1,'SymbolAllocation',[0 8],'PRBSet',(10:51))};

Create an uplink carrier configuration object, specifying the previously defined configurations.

cfg = nrULCarrierConfig( ...
    'SCSCarriers',carriers, ...
    'BandwidthParts',bwp, ...
    'SRS',srs, ...
    'PUSCH',pusch);

References

[1] 3GPP TS 38.211. “NR; Physical channels and modulation.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2021a

R2025a: Specify antenna mapping and precoding matrix

Use the AntennaMapping and PrecodingMatrix properties to specify the antenna mapping and a precoding matrix, respectively.

R2024b: Configure separate power scaling for each SRS in a period

Configure separate power scaling for each SRS in a period by setting the Power property to a vector of length equal to the number of allocated transmissions in a period.

R2024a: Specify eight antenna ports and enable cyclic shift and comb offset hopping in SRS transmissions

The object enables you to:

• Specify eight antenna ports through the NumSRSPorts property.

• Specify the use of eight-port TDM for SRS transmission through the EnableEightPortTDM property.

• Configure cyclic shift hopping and comb offset hopping in SRS transmissions through the CyclicShiftHopping, CyclicShiftHoppingID, CyclicShiftHoppingSubset, HoppingFinerGranularity, CombOffsetHopping, CombOffsetHoppingID, CombOffsetHoppingSubset, and HoppingWithRepetition properties.

R2023a: Release 17 updates for partial frequency sounding SRS transmissions

The object now supports SRS for partial frequency sounding, as defined in Release 17 of TS 38.211 Section 6.4.1.4.

• Use the FrequencyScalingFactor, StartRBIndex, and EnableStartRBHopping object properties to configure SRS transmissions for partial frequency sounding.

• The properties NumSRSSymbols, Repetition, KTC, and KBarTC now support the extended ranges that are defined in Release 17.