nrPRACHGrid

Generate PRACH resource grid

Syntax

grid = nrPRACHGrid(carrier,prach)

grid = nrPRACHGrid(carrier,prach,p)

grid = nrPRACHGrid(___,'OutputDataType',datatype)

Description

grid = nrPRACHGrid(carrier,prach) returns the physical random access channel (PRACH) resource grid for one antenna. The input carrier specifies carrier configuration parameters for a specific OFDM numerology. The input prach specifies PRACH configuration parameters.

grid = nrPRACHGrid(carrier,prach,p) returns the PRACH resource grid for p antennas.

grid = nrPRACHGrid(___,'OutputDataType',datatype) specifies the resource grid symbol data type in addition to the input arguments in any of the previous syntaxes.

Examples

Generate and Map PRACH Symbols to Grid

Configure the PRACH and the carrier with default properties.

carrier = nrCarrierConfig;
prach = nrPRACHConfig;

Generate PRACH symbols and indices using the specified carrier and PRACH configuration parameters.

prachSym = nrPRACH(carrier,prach);
prachInd = nrPRACHIndices(carrier,prach);

Generate a PRACH resource grid of all zeros.

prachGrid = nrPRACHGrid(carrier,prach);

Map the PRACH symbols to the PRACH resource grid by using the indices.

prachGrid(prachInd) = prachSym;

Input Arguments

carrier — Carrier configuration parameters

nrCarrierConfig object

Carrier configuration parameters for a specific OFDM numerology, specified as an nrCarrierConfig object.

prach — PRACH configuration parameters

nrPRACHConfig object

PRACH configuration parameters, specified as an nrPRACHConfig object. The function uses only these properties of this input.

• FrequencyRange

• DuplexMode

• ConfigurationIndex

• SubcarrierSpacing

p — Number of antennas

positive integer

Number of antennas, specified as a positive integer.

datatype — Data type of output symbols

'double' (default) | 'single'

Data type of the output symbols, specified as 'double' or 'single'.

Data Types: char | string

Output Arguments

grid — PRACH resource grid

K-by-L or K-by-L-by-p complex array of all zeros

PRACH resource grid, returned as a K-by-L or K-by-L-by-p complex array of all zeros.

• K is equal to (carrier.SubcarrierSpacing / prach.SubcarrierSpacing) × carrier.NSizeGrid × 12

• L is the number of OFDM symbols and depends on the PRACH format.

  • For long formats, L = prach.PRACHDuration.

  • For short format C0, L = 7.

  • For all other short formats, L = 14.

    For more information on PRACH preamble formats, see TS 38.211 Tables 6.3.3.1-1 and 6.3.3.1-2.

Data Types: double | single

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™.

The datatype input argument must be compile-time constant. For example, when specifying 'single' as the output data type, include {coder.Constant('OutputDataType'),coder.Constant('single')} in the -args value of the codegen function. For more information, see the coder.Constant (MATLAB Coder) class.

Version History

Introduced in R2020a