# ltePUCCH2DRSDecode

PUCCH format 2 DRS decoding

## Description

example

ack = ltePUCCH2DRSDecode(ue,chs,oack,sym) returns a vector of hybrid automatic repeat request (HARQ) indicator values, ack, obtained by performing PUCCH format 2 DRS decoding of the complex matrix, sym. The decoder uses a maximum likelihood (ML) approach, assuming that sym has already been equalized, to best restore the originally transmitted complex values. The symbols for each antenna are in the columns of sym. The number of columns in sym should match the number of PUCCH resource indices specified in the chs structure.

oack specifies the number of HARQ indicator values expected.

ack is a column vector containing oack HARQ indicator (HI) values.

## Examples

collapse all

Decode a PUCCH format 2A DM-RS from a synchronized and equalized resource array.

Initialize input configuration structures demonstrating use of 'Name',Value pair assignment and direct field assignment.

ue = struct('NULRB',6,'NCellID',0,'NSubframe',0,'Hopping','Off');
pucch2 = struct('ResourceIdx',0);
ue.CyclicPrefixUL = 'Normal';
ue.NTxAnts = 1;
pucch2.ResourceSize = 0;
pucch2.CyclicShifts = 0;

For the transmitter, create the PUCCH format 2A DM-RS.

reGrid = lteULResourceGrid(ue);
drsIndices = ltePUCCH2DRSIndices(ue,pucch2);
txAck = [1;0];
reGrid(drsIndices) = ltePUCCH2DRS(ue,pucch2,txAck);

On the receiver side, decode the PUCCH format 2 DM-RS symbols and view rxAck to confirm it matches txAck

rxAck = 2x1 logical array

1
0

## Input Arguments

collapse all

UE-specific configuration settings, specified as a structure that can contain the following fields.

Parameter FieldRequired or OptionalValuesDescription
NCellIDRequired

Integer from 0 to 503

Physical layer cell identity

NSubframeRequired

0 (default), nonnegative scalar integer

Subframe number

CyclicPrefixULOptional

'Normal' (default), 'Extended'

Cyclic prefix length

HoppingOptional

'Off' (default), 'Group'

Frequency hopping method.

NPUCCHIDOptional

Integer from 0 to 503

PUCCH virtual cell identity. If this field is not present, NCellID is used as the identity.

PUCCH channel settings, specified as a structure that can contain the following fields.

Parameter FieldRequired or OptionalValuesDescription
ResourceIdxOptional

0 (default), integer from 0 to 1185 or vector of integers.

PUCCH resource indices which determine the physical resource blocks, cyclic shift, and orthogonal cover used for transmission. (${n}_{PUCCH}^{\left(2\right)}$). Define one index for each transmission antenna.

ResourceSizeOptional

0 (default), integer from 0 to 98.

Size of resource allocated to PUCCH format 2 (${N}_{RB}^{\left(2\right)}$)

CyclicShiftsOptional

0 (default), integer from 0 to 7

Number of cyclic shifts used for format 1 in resource blocks (RBs) with a mixture of format 1 and format 2 PUCCH, specified as an integer from 0 to 7. (${N}_{cs}^{\left(1\right)}$)

oack specifies the number of HARQ indicator values expected, specified as nonnegative integer vector. The number of HARQ indicator values is 1 for PUCCH format 2A and 2 for PUCCH format 2B.

Data Types: double

Symbols for each antenna, specified as complex numeric matrix. The number of columns in sym should match the number of PUCCH resource indices specified in the chs structure.

Example: 0.25881 + 0.9659i

Data Types: double
Complex Number Support: Yes

## Output Arguments

collapse all

Hybrid ARQ indicator values, returned as a logical column vector. This output is obtained by performing PUCCH format 1 decoding of the complex matrix, sym.

Data Types: logical

## Version History

Introduced in R2014a