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nrSearchSpaceConfig

Search space set configuration parameters

Since R2020a

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Description

The nrSearchSpaceConfig object sets search space set configuration parameters for the physical downlink control channel (PDCCH), as defined in TS 38.213 Section 10 [1]. Use this object when setting the SearchSpace property of the nrPDCCHConfig or nrDLCarrierConfig objects.

Creation

Syntax

cfgSS = nrSearchSpaceConfig
cfgSS = nrSearchSpaceConfig(Name,Value)

Description

cfgSS = nrSearchSpaceConfig creates a search space set configuration object with default properties.

cfgSS = nrSearchSpaceConfig(Name,Value) specifies properties using one or more name-value pair arguments. Enclose each property in quotes. For example, 'Duration',3,'NumCandidates',[5 5 3 2 1] configures the search space set over three consecutive slots with the specified number of candidates at each aggregation level. Unspecified properties take their default values.

example

Properties

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Search space set ID, specified as a nonnegative integer.

Data Types: double

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

Data Types: char | string

Associated CORESET ID for the search space, specified as an integer from 0 to 11. When this object and nrCORESETConfig object specify the SearchSpace and CORESET properties, respectively, of the same nrPDCCHConfig object, the CORESETID properties of these objects must match.

Data Types: double

Search space type, specified as 'ue' or 'common'.

Data Types: char | string

First symbol of CORESET location in each monitored slot, specified as an integer from 0 to 13. Values from 0 to 11 apply only to extended cyclic prefix. When setting this property, the CORESET must fit within a single slot in terms of the associated CORESET duration.

Data Types: double

Slot period and offset for PDCCH monitoring, specified as a 1-by-2 integer vector. The first vector element specifies the period. The period must be a positive integer greater than or equal to the search space duration specified by the Duration property. The second vector element specifies the offset with respect to the period. The offset must be a nonnegative integer less than the period (the first vector element).

Data Types: double

Search space duration in slots, specified as an integer from 0 to 2559. This property specifies the number of consecutive slots that the search space lasts within each period. The value of this property must be less than or equal to the slot period specified by the SlotPeriodAndOffset property.

Data Types: double

Number of candidates per aggregation level, specified as a 1-by-5 integer vector. For each aggregation level, you can specify 0, 1, 2, 3, 4, 5, 6, or 8 candidates. The vector element values correspond to the number of candidates for aggregation levels AL1, Al2, AL4, Al8, and AL16, respectively.

Data Types: double

Examples

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Open Live Script

Configure the carrier with default configuration parameters. 

carrier = nrCarrierConfig;

Configure the CORESET with 6 frequency resources, a duration of 3 OFDM symbols, and a REG bundle size of 3.

crst = nrCORESETConfig;
crst.FrequencyResources = ones(1,6);
crst.Duration = 3;
crst.REGBundleSize = 3;

Configure the search space set for the PDCCH with the specified number of candidates at each aggregation level.

cfgSS = nrSearchSpaceConfig;
cfgSS.NumCandidates = [5 5 3 2 1];

Configure the PDCCH with the specified bandwidth part, CORESET, and search space set.

pdcch = nrPDCCHConfig;
pdcch.NStartBWP = 6;
pdcch.NSizeBWP = 36;
pdcch.CORESET = crst;
pdcch.SearchSpace = cfgSS;

Generate PDCCH DM-RS symbols for all candidates and aggregation levels. 

[~,allDMRS] = nrPDCCHSpace(carrier,pdcch)
allDMRS=5×1 cell array
    { 18x5 double}
    { 36x5 double}
    { 72x3 double}
    {144x2 double}
    {288x1 double}

Verify that the number of generated candidates for the PDCCH DM-RS symbols at each aggregation level matches the number of candidates specified by the search space set. 

numCandidates = [...
    size(allDMRS{1},2) ... 
    size(allDMRS{2},2) ... 
    size(allDMRS{3},2) ... 
    size(allDMRS{4},2) ... 
    size(allDMRS{5},2)];
isequaln(cfgSS.NumCandidates,numCandidates)
ans = logical
   1
Open Live Script

Configure a carrier grid of 60 resource blocks (RBs), where the starting RB index relative to the common resource block 0 (CRB 0) is 3. 

carrier = nrCarrierConfig;
carrier.NStartGrid = 3;
carrier.NSizeGrid = 60;

Configure noninterleaved CORESET with 6 frequency resources and a duration of 3 OFDM symbols.

crst = nrCORESETConfig;
crst.FrequencyResources = ones(1,6);
crst.Duration = 3;
crst.CCEREGMapping = 'noninterleaved';

Configure the search space set for the PDCCH with the specified number of candidates at each aggregation level.

cfgSS = nrSearchSpaceConfig;
cfgSS.NumCandidates = [5 5 3 2 1];

Configure the PDCCH with the specified bandwidth part, CORESET, and search space set.

pdcch = nrPDCCHConfig;
pdcch.NStartBWP = 5;
pdcch.NSizeBWP = 48;
pdcch.CORESET = crst;
pdcch.SearchSpace = cfgSS;

Generate PDCCH DM-RS resource element indices for all candidates and aggregation levels using 1-based, subscript indexing form relative to the BWP grid. 

[~,~,allDMRSInd] = nrPDCCHSpace(carrier,pdcch, ...
    'IndexOrientation','bwp','IndexStyle','subscript')
allDMRSInd=5×1 cell array
    { 18x3x5 uint32}
    { 36x3x5 uint32}
    { 72x3x3 uint32}
    {144x3x2 uint32}
    {288x3   uint32}

Verify that the number of generated candidates for PDCCH DM-RS indices at each aggregation level matches the number of candidates specified by the search space set.

numCandidates = [...
    size(allDMRSInd{1},3) ... 
    size(allDMRSInd{2},3) ... 
    size(allDMRSInd{3},3) ... 
    size(allDMRSInd{4},3) ... 
    size(allDMRSInd{5},3)];
isequaln(cfgSS.NumCandidates,numCandidates)
ans = logical
   1

References

[1] 3GPP TS 38.213. “NR; Physical layer procedures for control.” 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 R2020a

See Also

Functions

Objects