nrULSCHMultiplex
Perform UL-SCH data and control multiplexing
Description
[
returns codeword cw,info] = nrULSCHMultiplex(pusch,tcr,tbs,culsch,cack,ccsi1,ccsi2)cw by performing uplink shared channel (UL-SCH)
multiplexing on the encoded UL-SCH data and the encoded uplink control information (UCI), as
defined in TS 38.212 Section 6.2.7 [1]. 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.
The function internally calculates the number of reserved bits for the hybrid automatic
repeat request acknowledgment (HARQ-ACK) transmission, GACKRvd and then
compares against the lengths of the coded inputs. This comparison determines the processing
of the HARQ-ACK for rate-matching or puncturing.
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. The output
cw contains zeros when not enough encoded UL-SCH and encoded UCI
(HARQ-ACK, channel state information (CSI) 1, or CSI part 2) data is present to achieve the
bit capacity. The function also returns the structure info, which
contains information about the 1-based locations of each type in the codeword.
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]
Input Arguments
Output Arguments
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.