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DCI

 

The main purpose of DCI (Downlink Control Information) is the same as DCI in LTE(I strongly recommend you to read LTE DCI page first if you are not so familiar with what the DCI does). That is, it is a special set of information which schedules downlink data channel (e.g, PDSCH) or uplink data channel (e.g, PUSCH).

 

Followings are the list of DCI types and its contents defined in 38.212 - 7.3 Downlink control information.

 

NOTE : The contents of the table shown here is based on 38.212 V2.0.0

 

 

Format 0_0

 

This is used for the scheduling of PUSCH in one cell.

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

Frequency domain resource assignment

N

Variable with UL BWP N_RB.

Indicate PRB location within the BWP.

It is expressed in a formula shown here.

Time domain resource assignment

X

 

Frequency Hopping Flag

1

 

Modulation and coding scheme

5

38.214 - 6.1.4 (Not Specified Yet)

New data indicator

1

 

Redundancy version

2

38.214 - 6.1.4 (Not Specified Yet)

HARQ process number

4

 

TPC command for scheduled PUSCH

2

38.213 - Table 7.1.1-1

UL/SUL indicator

0 or 1

0 bit : SUL not figured

1 bit : SUL configured

 

 

< Frequency domain resource assignment >

 

< 38.213 v2.0.0 - Table 7.1.1-1: Mapping of TPC Command Field in DCI format 0_0, DCI format 0_1, or DCI format 2_2, or DCI format 2_3 having CRC parity bits scrambled by TPC-PUSCH-RNTI or TPC-SRS-RNTI, to absolute and accumulated  d_PUSCH,c values >

 

 

Format 0_1

 

This is used for the scheduling of PUSCH in one cell.

 

Field (Item)

Bits

Reference

Carrier indicator

3

 

Identifier for DCI formats

1

 

Bandwidth part indicator

0,1,2

Determined by BandwidthPart-Config in higher layer message and 38.212 - Table 7.3.1.1.2-1

Frequency domain resource assignment

Variable

Variable with Resource Allocation Type

Time domain resource assignment

1,2,3,4

 

VRB-to-PRB mapping

1

 
Frequency Hopping Flag

0,1

 

Modulation and coding scheme

5

 

New data indicator

1

 

Redundancy version

2

 

HARQ process number

4

 

1st Downlink assignment index

1,2

 

2nd Downlink assignment index

0,2

 

TPC command for scheduled PUSCH

2

 

SRS resource indicator

Variable

 

Precoding information and number of layers

0,2,3,4,5,6

 

Antenna ports

2,3,4,5

 

SRS request

2

 

CSI request

0,1,2,3,4,5,6

Determined by ReportTriggerSize in higher layer message

CBG transmission information

0,2,4,6,8

determined by maxCodeBlockGroupPerTransportblock in higher layer message

PTRS - DMRS Association

0,2

 
beta_offsetr Indicator

0,2

 
DMRS Sequence Initialization

0,2

 
UL/SUL Indicator

0,1

 

 

< BandwidthPart-Config >

BandwidthPart-Config ::= SEQUENCE {

    downlinkBandwidthPartsToReleaseList SEQUENCE (SIZE (1..maxNrofBandwidthParts)) OF BandiwdthPartId   ,

    downlinkBandwidthPartsToAddModList  SEQUENCE (SIZE (1..maxNrofBandwidthParts)) OF BandwidthPart ,

    defaultDownlinkBwp-Id               BandiwdthPartId                                         

    uplinkBandwidthPartsToReleaseList   SEQUENCE (SIZE (1..maxNrofBandwidthParts)) OF BandiwdthPartId   ,

    uplinkBandwidthPartsToAddModList    SEQUENCE (SIZE (1..maxNrofBandwidthParts)) OF BandwidthPart,

    bandwidthPartInactivityTimer        SetupRelease { ENUMERATED {FFS: Value range }}                                              

 

BandwidthPart ::=   SEQUENCE {

    bandwidthPartId     BandiwdthPartId,

    location        INTEGER (0.. maxNrofPhysicalResourceBlocksTimes4)   OPTIONAL,

    bandwidth       INTEGER (1.. maxNrofPhysicalResourceBlocks)     OPTIONAL,

    subcarrierSpacing   ENUMERATED {n0, n1, n2, n3, n4}             OPTIONAL,

    cyclicPrefix        ENUMERATED { extended }                 OPTIONAL,

    directCurrentLocation   INTEGER (0..3299)                   OPTIONAL, -- Cond UplinkOnly

}

 

BandwidthPartId ::=INTEGER (0..maxNrofBandwidthParts-1)

 

 

< 38.212 v2.0.0 - Table 7.3.1.1.2-1: Bandwidth part indicator  >

Value of BWP indicator field

Bandwidth part

1 bit

2 bits

0

0

First bandwidth part configured by higher layers

1

1

Second bandwidth part configured by higher layers

 

10

Third bandwidth part configured by higher layers

 

11

Fourth bandwidth part configured by higher layers

 

 

 

Format 1_0

 

This is used for the scheduling of PDSCH in one cell.

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

Bandwidth part indicator

2

 

Frequency domain resource assignment

Variable

Variable with BWP N_RB

Time domain resource assignment

X

 

VRB-to-PRB mapping

1

 

Modulation and coding scheme

5

 

New data indicator

1

 

Redundancy version

2

 

HARQ process number

4

 

Downlink assignment index

2

 

TPC command for scheduled PUCCH

2

 

PUCCH resource indicator

2

 

PDSCH-to-HARQ_feedback timing indicator

3

 

 

 

Format 1_1

 

This is used for the scheduling of PDSCH in one cell.

 

Field (Item)

Bits

Reference

Carrier indicator

0,3

 

Identifier for DCI formats

1

 

Bandwidth part indicator

0,1,2

 

Frequency domain resource assignment

Variable

Variable with Resource Allocation Type

Time domain resource assignment

1,2,3,4

 

VRB-to-PRB mapping

0,1

 

PRB bundling size indicator

0,1

 

Rate matching indicator

0,1,2

 

Modulation and coding scheme [TB1]

5

 

New data indicator [TB1]

1

 

Redundancy version [TB1]

2

 

Modulation and coding scheme [TB2]

5

 

New data indicator [TB2]

1

 

Redundancy version [TB2]

2

 

HARQ process number

4

 

Downlink assignment index

0,4

 

TPC command for scheduled PUCCH

2

 

PUCCH resource indicator

2

 

PDSCH-to-HARQ_feedback timing indicator

3

 

Antenna port(s) and number of layers

1,2,3,4,5,6

 

Transmission configuration indication

0,3

 

CSI request

2

 

CBG transmission information

0,2,4,6,8

 

CBG flushing out information

0,1

 

DMRS sequence initialization

1

 

 

 

Format 2_0

 

This is used for notifying the slot format.

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

Slot format indicator

Variable

 

 

 

Format 2_1

 

This is used for notifying the PRB(s) and OFDM symbol(s) where UE may assume no transmission is intended for the UE.

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

Pre-emption indication

Variable

 

 

 

Format 2_2

 

This is used for the transmission of TPC commands for PUCCH, PUSCH

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

TPC command number 1, TPC command number 2,, TPC command number N

Variable

 

 

 

Format 2_3

 

This is used for the transmission of a group of TPC commands for SRS transmissions by one or more UEs. Along with a TPC command, a SRS request may also be transmitted.

 

Field (Item)

Bits

Reference

Identifier for DCI formats

1

 

block number 1, block number 2,, block number B

Variable

 
SRS Request

0,2

 
TPC Command Number

2

 

 

 

 

Reference

 

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