Slot format is defined in a big table in 38.213-Table 11.1.1-1: Slot formats for normal cyclic prefix. An important question is how to determine which slot format is used in a specific slot and how those information is notified to UE. This process is done by the combination of several RRC paramters shown below and DCI 2_0.

SlotFormatIndicator ::= SEQUENCE {

    sfi-RNTI                                     RNTI-Value,

    dci-PayloadSize                           INTEGER (1..maxSFI-DCI-PayloadSize),

    slotFormatCombToAddModList       SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup))

                                                                     OF  SlotFormatCombinationsPerCell,

    slotFormatCombToReleaseList       SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup)) OF ServCellIndex,  

    availableRB-SetsToAddModList-r16          SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup)) OF

                                                                           AvailableRB-SetsPerCell-r16 ,

    availableRB-SetsToRelease-r16      SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup)) OF ServCellIndex

    switchTriggerToAddModList-r16     SEQUENCE (SIZE(1..4)) OF SearchSpaceSwitchTrigger-r16,

    switchTriggerToReleaseList-r16     SEQUENCE (SIZE(1..4)) OF ServCellIndex OPTIONAL,

    co-DurationsPerCellToAddModList-r16      SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup)) OF

                                                                     CO-DurationsPerCell-r16,

    co-DurationsPerCellToReleaseList-r16       SEQUENCE (SIZE(1..maxNrofAggregatedCellsPerCellGroup)) OF

                                                                     ServCellIndex

}

SlotFormatCombinationsPerCell ::= SEQUENCE {

     servingCellId                             ServCellIndex,

     subcarrierSpacing                      SubcarrierSpacing,

     subcarrierSpacing2                     SubcarrierSpacing,

     slotFormatCombinations              SEQUENCE (SIZE (1..maxNrofSlotFormatCombinationsPerSet)) OF

                                                              SlotFormatCombination

     positionInDCI                            INTEGER(0..maxSFI-DCI-PayloadSize-1),

     ...,

     [[

          enableConfiguredUL-r16        ENUMERATED {enabled}

     ]]

}

SlotFormatCombination ::= SEQUENCE {

     slotFormatCombinationId            SlotFormatCombinationId,

     slotFormats                             SEQUENCE (SIZE (1..maxNrofSlotFormatsPerCombination)) OF INTEGER (0..255)

}

SlotFormatCombinationId ::= INTEGER (0..maxNrofSlotFormatCombinationsPerSet-1)

CO-DurationsPerCell-r16 ::= SEQUENCE {

    servingCellId-r16                       ServCellIndex,

    positionInDCI-r16                      INTEGER(0..maxSFI-DCI-PayloadSize-1),

    subcarrierSpacing-r16                SubcarrierSpacing,

    co-DurationList-r16                   SEQUENCE (SIZE(1..64)) OF CO-Duration-r16

}

CO-Duration-r16 ::= INTEGER (0..1120)

AvailableRB-SetsPerCell-r16 ::= SEQUENCE {

    servingCellId-r16                           ServCellIndex,

    positionInDCI-r16                          INTEGER(0..maxSFI-DCI-PayloadSize-1)

}

SearchSpaceSwitchTrigger-r16 ::= SEQUENCE {

    servingCellId-r16                           ServCellIndex,

    positionInDCI-r16                          INTEGER(0..maxSFI-DCI-PayloadSize-1)

}

maxSFI-DCI-PayloadSize                                INTEGER ::= 128

maxNrofAggregatedCellsPerCellGroup                INTEGER ::= 16

maxNrofSlotFormatCombinationsPerSet             INTEGER ::= 512

maxNrofSlotFormatsPerCombination                  INTEGER ::= 256

<38.213 v15.7 -Table 11.1.1-1: Slot formats for normal cyclic prefix>

D : Downlink, U : Uplink, F : Flexible

Reference

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