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nrPDSCHPTRSIndices

Generate PDSCH PT-RS Indices

Description

example

ind = nrPDSCHPTRSIndices(carrier,pdsch) returns ind, which contains 1-based phase tracking reference signal (PT-RS) resource elements (RE) of the physical downlink shared channel (PDSCH), as defined in TS 38.211 Section 7.4.1.2.2 [1]. The function returns ind in linear form, for given carrier configuration carrier and physical downlink shared channel configuration pdsch.

ind = nrPDSCHPTRSIndices(carrier,pdsch,Name,Value) specifies output formatting options by using one or more name-value pair arguments. Unspecified options take default values.

Examples

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Create a carrier configuration object with default properties. This object corresponds to a 10 MHz carrier.

carrier = nrCarrierConfig;

Create a default PDSCH configuration object, and then enable the PT-RS configuration.

pdsch = nrPDSCHConfig;
pdsch.EnablePTRS = 1;

Create a PDSCH phase tracking reference signal (PT-RS) configuration object with specified properties.

ptrs = nrPDSCHPTRSConfig;
ptrs.TimeDensity = 2;
ptrs.FrequencyDensity = 4;
ptrs.REOffset = '10';

Assign the PDSCH PT-RS configuration object to PTRS property of PDSCH configuration object.

pdsch.PTRS = ptrs;

Generate PDSCH PT-RS symbols of data type single.

sym = nrPDSCHPTRS(carrier,pdsch,'OutputDataType','single')
sym = 78x1 single column vector

  -0.7071 - 0.7071i
  -0.7071 - 0.7071i
   0.7071 - 0.7071i
   0.7071 - 0.7071i
   0.7071 - 0.7071i
  -0.7071 - 0.7071i
  -0.7071 + 0.7071i
  -0.7071 - 0.7071i
  -0.7071 + 0.7071i
   0.7071 + 0.7071i
      ⋮

Generate PDSCH PT-RS indices in subscript form and set the index orientation to bandwidth part.

ind = nrPDSCHPTRSIndices(carrier,pdsch,'IndexStyle','subscript','IndexOrientation','bwp')
ind = 78x3 uint32 matrix

    19     1     1
    67     1     1
   115     1     1
   163     1     1
   211     1     1
   259     1     1
   307     1     1
   355     1     1
   403     1     1
   451     1     1
      ⋮

Input Arguments

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Carrier configuration parameters for a specific OFDM numerology, specified as an nrCarrierConfig object. This function uses only these properties of the nrCarrierConfig object.

Property FieldValuesDescription
SubcarrierSpacing

15 (default), 30, 60, 120, 240

Subcarrier spacing in kHz

CyclicPrefix

'normal' (default), 'extended'

Cyclic prefix length, specified as one of these options.

  • 'normal' corresponds to 14 OFDM symbols in a slot.

  • 'extended' corresponds to 12 OFDM symbols in a slot.

For the numerologies specified in TS 38.211 Section 4.2, extended cyclic prefix length applies only for 60 kHz subcarrier spacing.

NSizeGrid

52 (default), integer from 1 to 275

Number of resource blocks in the carrier resource grid

NStartGrid

0 (default), integer from 0 to 2199

Start of carrier resource grid relative to common resource block 0 (CRB 0)

NSlot

0 (default), nonnegative integer scalar

Slot number. You can set NSlot to a value larger than the number of slots per frame.

PDSCH configuration parameters, specified as an nrPDSCHConfig object. This function only uses these nrPDSCHConfig object properties.

Property FieldValuesDescription
NSizeBWP

[] (default), integer from 1 to 275

Size of the bandwidth part (BWP) in terms of number of physical resource blocks (PRBs). The default value of [] implies that the value is equal to NSizeGrid of carrier input argument.

NStartBWP

[] (default), integer from 0 to 2473

Starting PRB index of BWP relative to CRB 0. The default value of [] implies that the value is equal to NStartGrid of carrier input argument.

ReservedPRB

nrPDSCHReservedConfig (default), cell array of nrPDSCHReservedConfig objects

Reserved PRBs and OFDM symbols pattern in BWP, specified as a cell array of objects, of class nrPDSCHReservedConfig.

ReservedRE

[] (default), nonnegative integer vector

Reserved resource elements (RE) indices within the BWP

NumLayers

1 (default), integer from 1 to 8

Number of transmission layers. For one codeword, use an integer between 1 to 4. For two codewords, use an integer between 5 to 8.

MappingType

'A' (default), 'B'

Mapping type of PDSCH

SymbolAllocation

[0 14] (default), two-element vector of nonnegative integers

OFDM symbols allocated for PDSCH

PRBSet

[0:51] (default), vector of nonnegative integer from 0 to 274

PRBs allocated for PDSCH within the BWP

RNTI

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

Radio network temporary identifier of the user equipment

DMRS

nrPDSCHDMRSConfig configuration object

DMRS configuration object only uses these properties.

  • DMRSConfigurationType

  • DMRSTypeAPosition

  • DMRSLength

  • DMRSAdditionalPosition

  • CustomSymbolSet

  • DMRSPortSet

For more information, see nrPDSCHDMRSConfig.

EnablePTRS

0 (default), 1

PT-RS configuration, specified as one of these values.

  • 0 — Disable PT-RS configuration.

  • 1 — Enable PT-RS configuration.

PTRS

nrPDSCHPTRSConfig configuration object

PDSCH PT-RS configuration, specified as a nrPDSCHPTRSConfig configuration object.

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: 'IndexStyle','subscript','IndexBase','0based' specifies the RE indexing form and base, respectively, of the output.

Resource element indexing form, specified as the comma-separated pair consisting of 'IndexStyle' and one of these values:

  • 'index' — The indices are in linear index form.

  • 'subscript' — The indices are in [subcarrier, symbol, antenna] subscript row form.

Data Types: char | string

Resource element indexing base, specified as the comma-separated pair consisting of 'IndexBase' and one of these values:

  • '1based' — The index counting starts from one.

  • '0based' — The index counting starts from zero.

Data Types: char | string

Indexing orientation of resource elements, specified as the comma-separated pair consisting of 'IndexOrientation' and one of these values:

  • 'carrier' — Indices are referenced with respect to carrier grid.

  • 'bwp' — Indices are referenced with respect to bandwidth part.

Data Types: char | string

Output Arguments

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PT-RS resource element indices, returned as one of these values.

  • Column vector — The function returns this type of value when 'IndexStyle' is set to 'index'.

  • M-by-3 matrix — The function returns this type of value when 'IndexStyle' is set to 'subscript'. The matrix rows correspond to the [subcarrier, symbol, antenna] subscripts based on the number of subcarriers, OFDM symbols, and number of antennas, respectively.

Depending on the value of 'IndexBase', the function returns either 1-based or 0-based indices. Depending on the value of 'IndexOrientation', the function returns either carrier oriented indices or BWP oriented indices.

Data Types: uint32

References

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

Extended Capabilities

Introduced in R2020a