nrULSCHMultiplex

Perform UL-SCH data and control multiplexing

Since R2020b

Syntax

[cw,info] = nrULSCHMultiplex(pusch,tcr,tbs,culsch,cack,ccsi1,ccsi2)

Description

[cw,info] = nrULSCHMultiplex(pusch,tcr,tbs,culsch,cack,ccsi1,ccsi2) performs uplink shared channel (UL-SCH) multiplexing on encoded UL-SCH data and encoded uplink control information (UCI), as defined in TS 38.212 Section 6.2.7 [1]. The function returns one or two multiplexed codewords cw and location information info about the multiplexing for the specified inputs. pusch is the physical uplink shared channel configuration (PUSCH). tcr is the target code rate. tbs is the transport block size for the UL-SCH transmission. culsch is the encoded UL-SCH data. cack, ccsi1, and ccsi2 are the encoded UCI types.

Examples

Generate Codeword with Predefined Coded UL-SCH Data and Coded UCI Types

Create a default PUSCH configuration object. Allocate the first 21 resource blocks of the bandwidth part to the PUSCH.

pusch = nrPUSCHConfig;
pusch.PRBSet = 0:20;

Set the target code rate, payload lengths of the UL-SCH data, HARQ-ACK, CSI part 1, and CSI part 2.

tcr = 0.5;  % Target code rate
tbs = 100;  % Payload length of UL-SCH data (transport block size)
oack = 3;   % Payload length of HARQ-ACK
ocsi1 = 10; % Payload length of CSI part 1
ocsi2 = 10; % Payload length of CSI part 2

Get the rate matched lengths of the UL-SCH data, HARQ-ACK, CSI part 1, and CSI part 2.

rmInfo = nrULSCHInfo(pusch,tcr,tbs,oack,ocsi1,ocsi2);

Create the predefined coded bits of the UL-SCH, HARQ-ACK, CSI part 1, and CSI part 2 for the rate-matched output length obtained from the rmInfo structure.

culsch = ones(rmInfo.GULSCH,1);
cack = 2*ones(rmInfo.GACK,1);
ccsi1 = 3*ones(rmInfo.GCSI1,1);
ccsi2 = 4*ones(rmInfo.GCSI2,1);

Get the codeword from the predefined coded UL-SCH data and coded UCI types.

cw = nrULSCHMultiplex(pusch,tcr,tbs,culsch,cack,ccsi1,ccsi2);

To see the multiplexing operation, plot the codeword. The codeword starts with the elements of CSI part 1, followed by HARQ-ACK, CSI part 1, CSI part 2, and the mix of UL-SCH data and CSI part 2.

plot(cw)
xlabel('Codeword Indices')
ylabel('Codeword Values')
title('Multiplexing Operation')

Generate Codeword with Coded UL-SCH Data and Coded UCI

Create a PUSCH configuration object with a pi/2-BPSK modulation scheme and no frequency hopping. Set the beta offset factor for HARQ-ACK to 20, and the beta offset factor for CSI part 1 and CSI part 2 to 6.25 each. Specify the scaling factor as 0.8, which limits the number of resource elements (REs) assigned for the UCI.

pusch = nrPUSCHConfig;
pusch.Modulation = 'pi/2-BPSK';
pusch.FrequencyHopping = 'neither';
pusch.BetaOffsetACK = 20;
pusch.BetaOffsetCSI1 = 6.25;
pusch.BetaOffsetCSI2 = 6.25;
pusch.UCIScaling = 0.8;

Set the target code rate, payload lengths of the UL-SCH data, HARQ-ACK, CSI part 1, and CSI part 2.

tcr = 0.5;   % Target code rate
tbs = 1032;  % Payload length of UL-SCH data (transport block size)
oack = 8;    % Payload length of HARQ-ACK
ocsi1 = 88;  % Payload length of CSI part 1
ocsi2 = 720; % Payload length of CSI part 2

Get the rate matched lengths of the data, HARQ-ACK, CSI part 1, and CSI part 2.

rmInfo = nrULSCHInfo(pusch,tcr,tbs,oack,ocsi1,ocsi2);

Create the random payload bits for the UL-SCH data, HARQ-ACK, CSI part 1, and CSI part 2.

data = randi([0 1],tbs,1);
ack  = randi([0 1],oack,1);
csi1 = randi([0 1],ocsi1,1);
csi2 = randi([0 1],ocsi2,1);

Create a UL-SCH encoder System object.

encUL = nrULSCH;

Load the transport block into the UL-SCH encoder.

setTransportBlock(encUL,data);

Get the coded bits of length rmInfo.GULSCH by calling the encoder.

rv = 0; % Redundancy version is 0
culsch = encUL(pusch.Modulation,pusch.NumLayers,rmInfo.GULSCH,rv);

Encode the random payload of the HARQ-ACK, CSI part 1, and CSI part 2 for the rate-matched output lengths obtained from the rmInfo structure.

cack  = nrUCIEncode(ack,rmInfo.GACK,pusch.Modulation);
ccsi1 = nrUCIEncode(csi1,rmInfo.GCSI1,pusch.Modulation);
ccsi2 = nrUCIEncode(csi2,rmInfo.GCSI2,pusch.Modulation);

Get the codeword from the coded bits of the UL-SCH and the coded bits of UCI types.

[cw,info] = nrULSCHMultiplex(pusch,tcr,tbs,culsch,cack,ccsi1,ccsi2)

cw = 8112x1 int8 column vector

   1
   0
   1
   0
   0
   0
   1
   1
   1
   0
      ⋮

info = struct with fields:
    ULSCHIndices: [1622x1 uint32]
      ACKIndices: [1159x1 uint32]
     CSI1Indices: [4482x1 uint32]
     CSI2Indices: [849x1 uint32]
     UCIXIndices: [0x1 uint32]
     UCIYIndices: [0x1 uint32]
            QUCI: 0

Input Arguments

pusch — PUSCH configuration parameters

nrPUSCHConfig object

PUSCH configuration parameters, specified as an nrPUSCHConfig object. This function uses only these nrPUSCHConfig object properties:

• Modulation

• NumLayers

• MappingType

• SymbolAllocation

• PRBSet

• TransformPrecoding

• FrequencyHopping

• RNTI

• BetaOffsetAck

• UCIScaling

• DMRS

• EnablePTRS

• PTRS

tcr — Target code rate

scalar in the range (0, 1) | two-element vector (since R2024a)

Target code rate for the codewords in the UL-SCH transmission, specified as a scalar in the range (0, 1) or a two-element vector of numeric values in the range (0, 1) for two codewords. When you specify this input as a scalar and there are two codewords, the specified scalar applies to both codewords.

Data Types: double

tbs — Transport block size

nonnegative integer | two-element vector of nonnegative integers (since R2024a)

Transport block size associated with the codewords in the UL-SCH transmission, specified as a nonnegative integer or a two-element vector of nonnegative integers for two codewords. When you specify this input as a nonnegative integer and there are two codewords, the specified value applies to both codewords. A value of 0 indicates no transport block or no UL-SCH transmission on the PUSCH.

Data Types: double

culsch — Encoded and rate-matched UL-SCH data bits

binary-valued column vector | cell array of one or two column vectors (since R2024a) | []

Encoded and rate-matched UL-SCH data bits, specified as one of these values:

• Binary-valued column vector — Use this option for a single codeword transmission.

• Cell array of one or two binary-valued column vectors — You can use this option for a single codeword or a two-codeword transmission, respectively. When processing two-codeword transmission, UCI is multiplexed only on the codeword with the highest modulation and coding scheme index, I_MCS. If the two codewords have the same I_MCS, the UCI is multiplexed on the first codeword.

• [] — Use this option to indicate the absence of UL-SCH data transmission. If you specify the tbs input argument as 0, the culsch input argument must be empty.

The length of each codeword in culsch must be a multiple of their respective modulation order times the number of transmission layers. To obtain this length, use the GULSCH field of the info output from the nrULSCHInfo function.

Data Types: int8 | double

cack — Coded HARQ-ACK bits

real-valued column vector | []

Coded hybrid automatic repeat request acknowledgment (HARQ-ACK) bits, specified as one of these values:

• Real-valued column vector — The length of the vector must be a multiple of the modulation order times the number of transmission layers of the codeword on which the UCI is multiplexed. To obtain this length, use the GACK field of the info output from the nrULSCHInfo function.

• [] — Use this option to indicate the absence of HARQ-ACK transmission.

The nominal values of the HAQR-ACK bits are 0, 1, -1, and -2.

Data Types: int8 | double

ccsi1 — Coded CSI part 1 bits

real-valued column vector | []

Coded CSI part 1 bits, specified as one of these values:

• Real-valued column vector — The length of the vector must be a multiple of the modulation order times the number of transmission layers of the codeword on which the UCI is multiplexed. To obtain this length, use the GCS1 field of the info output from the nrULSCHInfo function.

• [] — Use this option to indicate the absence of the CSI part 1 transmission.

The nominal values of the CSI part 1 bits are 0, 1, -1, and -2.

Data Types: int8 | double

ccsi2 — Coded CSI part 2 bits

real-valued column vector | []

Coded CSI part 2 bits, specified as one of these values:

• Real-valued column vector — The length of the vector must be a multiple of the modulation order times the number of transmission layers of the codeword on which the UCI is multiplexed. To obtain this length, use the GCS2 field of the info output from the nrULSCHInfo function.

• [] — Use this option to indicate the absence of the CSI part 2 transmission.

The nominal values of the CSI part 2 bits are 0, 1, -1, and -2. Nominally, CSI part 2 is present only when CSI part 1 is present.

Data Types: int8 | double

Output Arguments

cw — One or two multiplexed codewords

real-valued column vector | cell array of one or two column vectors (since R2024a) | []

One or two multiplexed codewords for the PUSCH transmission, returned as one of these values:

• Real-valued column vector — The function returns this value when you specify culsch as a vector.

• Cell array of one or two real-valued column vectors — The function returns this value when you specify culsch as a cell array of one or two vectors, respectively.

• [] — The function returns this value in any of these cases:

  • When the PRBSet property of the pusch argument is [].

  • When the SymbolAllocation property of the pusch argument is [] or when the number of contiguous OFDM symbols allocated for PUSCH is 0.

  • When the culsch, cack, ccsi1, and ccsi2 inputs are empty.

If any of the input data types is int8, the output data type of the codeword is also int8. The nominal values of the bits in the codewords are 0, 1, -1, and -2.

The length of cw equals the bit capacity of the PUSCH. cw contains the encoded information up to the bit capacity of PUSCH and ignores any other additional information in the inputs. If there is not enough encoded UL-SCH and encoded UCI data to achieve the bit capacity, cw contains zeros. To determine the processing of HARQ-ACK for rate-matching or puncturing, the function compares the number of bits reserved for HARQ-ACK transmission against the lengths of coded inputs.

Data Types: int8 | double

info — 1-based location information

structure

1-based location information about the multiplexing, returned as a structure containing these fields. The output data type of each field is uint32. For two codewords, each field is returned as a 1-by-2 vector (since R2024a).

Field	Description
ULSCHIndices	Locations of coded UL-SCH bits in the codeword
ACKIndices	Locations of coded HARQ-ACK bits in the codeword
CSI1Indices	Locations of coded CSI part 1 bits in the codeword
CSI2Indices	Locations of coded CSI part 2 bits in the codeword
UCIXIndices	Locations of X UCI placeholders in the codeword
UCIYIndices	Locations of Y UCI placeholders in the codeword
QUCI (since R2024a)	Codeword number of the codeword on which the UCI is multiplexed

If the returned codeword, cw, is an empty array, each field in this structure is also an empty array.

References

[1] 3GPP TS 38.212. “NR; Multiplexing and channel coding.” 3rd Generation Partnership Project; Technical Specification Group Radio Access Network.

[2] 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 R2020b

R2024a: Support for two-codeword configurations

The function adds support for two-codeword configurations through the tbs, tcr, pusch, and culsch input arguments and the cw and info output arguments.