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Content for  TS 38.321  Word version:  18.0.0

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5 MAC procedures  5.1 Random Access procedure  5.1.1 Random Access procedure initialization  5.1.1a Initialization of variables specific to Random Access type  5.1.1b Selection of the set of Random Access resources for the Random Access procedure  5.1.1c Availability of the set of Random Access resources  5.1.1d Selection of the set of Random Access resources based on feature prioritization  5.1.1e Selection of Msg1 repetition for SI request 
...

 

5  MAC procedures  p. 19

5.1  Random Access procedure  p. 19

5.1.1  Random Access procedure initialization  p. 19

The Random Access procedure described in this clause is initiated by a PDCCH order, by the MAC entity itself, or by RRC for the events in accordance with TS 38.300. There is only one Random Access procedure ongoing at any point in time in a MAC entity. The Random Access procedure on an SCell or an LTM candidate cell shall only be initiated by a PDCCH order with ra-PreambleIndex different from 0b000000.
When a Random Access procedure is initiated, UE selects a set of Random Access resources as specified in clause 5.1.1b and initialises the following parameters for the Random Access procedure according to the values configured by RRC for the selected set of Random Access resources:
  • prach-ConfigurationIndex: the available set of PRACH occasions for the transmission of the Random Access Preamble for Msg1. These are also applicable to the MSGA PRACH if the PRACH occasions are shared between 2-step and 4-step RA types;
  • prach-ConfigurationPeriodScaling-IAB: the scaling factor defined in TS 38.211 and applicable to IAB-MTs, extending the periodicity of the PRACH occasions baseline configuration indicated by prach-ConfigurationIndex;
  • prach-ConfigurationFrameOffset-IAB: the frame offset defined in TS 38.211 and applicable to IAB-MTs, altering the ROs frame defined in the baseline configuration indicated by prach-ConfigurationIndex;
  • prach-ConfigurationSOffset-IAB: the subframe/slot offset defined in TS 38.211 and applicable to IAB-MTs, altering the ROs subframe or slot defined in the baseline configuration indicated by prach-ConfigurationIndex;
  • msgA-PRACH-ConfigurationIndex: the available set of PRACH occasions for the transmission of the Random Access Preamble for MSGA in 2-step RA type;
  • preambleReceivedTargetPower: initial Random Access Preamble power for 4-step RA type;
  • msgA-PreambleReceivedTargetPower: initial Random Access Preamble power for 2-step RA type;
  • rsrp-ThresholdSSB: an RSRP threshold for the selection of the SSB for 4-step RA type. If the Random Access procedure is initiated for beam failure recovery, rsrp-ThresholdSSB used for the selection of the SSB within candidateBeamRSList refers to rsrp-ThresholdSSB in BeamFailureRecoveryConfig IE;
  • rsrp-ThresholdCSI-RS: an RSRP threshold for the selection of CSI-RS for 4-step RA type. If the Random Access procedure is initiated for beam failure recovery, rsrp-ThresholdCSI-RS is equal to rsrp-ThresholdSSB in BeamFailureRecoveryConfig IE;
  • msgA-RSRP-ThresholdSSB: an RSRP threshold for the selection of the SSB for 2-step RA type;
  • rsrp-ThresholdSSB-SUL: an RSRP threshold for the selection between the NUL carrier and the SUL carrier;
  • msgA-RSRP-Threshold: an RSRP threshold for selection between 2-step RA type and 4-step RA type when both 2-step and 4-step RA type Random Access Resources are configured in the UL BWP;
  • rsrp-ThresholdMsg1-RepetitionNum2: an RSRP threshold for Msg1 repetition with repetition number 2 (see clause 5.1.1b);
  • rsrp-ThresholdMsg1-RepetitionNum4: an RSRP threshold for Msg1 repetition with repetition number 4 (see clause 5.1.1b);
  • rsrp-ThresholdMsg1-RepetitionNum8: an RSRP threshold for Msg1 repetition with repetition number 8 (see clause 5.1.1b);
  • rsrp-ThresholdMsg3: an RSRP threshold for Msg3 repetition (see clause 5.1.1b);
  • FeatureCombination: feature or a combination of features associated with a set of Random Access resources;
  • featurePriorities: priorities for features, such as (e)RedCap, Slicing, etc. (see clause 5.1.1d);
  • msgA-TransMax: The maximum number of MSGA transmissions when both 4-step and 2-step RA type Random Access Resources are configured;
  • candidateBeamRSList: a list of reference signals (CSI-RS and/or SSB) identifying the candidate beams for recovery and the associated Random Access parameters;
  • recoverySearchSpaceId: the search space identity for monitoring the response of the beam failure recovery request;
  • powerRampingStep: the power-ramping factor;
  • msgA-PreamblePowerRampingStep: the power ramping factor for MSGA preamble;
  • powerRampingStepHighPriority: the power-ramping factor in case of prioritized Random Access procedure;
  • scalingFactorBI: a scaling factor for prioritized Random Access procedure;
  • ra-PreambleIndex: Random Access Preamble;
  • ra-ssb-OccasionMaskIndex: defines PRACH occasion(s) associated with an SSB in which the MAC entity may transmit a Random Access Preamble (see clause 7.4);
  • msgA-SSB-SharedRO-MaskIndex: Indicates the subset of 4-step RA type PRACH occasions shared with 2-step RA type PRACH occasions for each SSB. If 2-step RA type PRACH occasions are shared with 4-step RA type PRACH occasions and msgA-SSB-SharedRO-MaskIndex is not configured, then all 4-step RA type PRACH occasions are available for 2-step RA type (see clause 7.4);
  • ssb-SharedRO-MaskIndex: defines PRACH occasions, on which preambles are allocated for a feature or a combination of features, associated with an SSB in which the MAC entity may transmit a Random Access Preamble (see clause 7.4);
  • ra-OccasionList: defines PRACH occasion(s) associated with a CSI-RS in which the MAC entity may transmit a Random Access Preamble;
  • ra-PreambleStartIndex: the starting index of Random Access Preamble(s) for on-demand SI request;
  • startPreambleForThisPartition: the first preamble associated with the set of Random Access Resources applicable to the Random Access procedure;
  • preambleTransMax: the maximum number of Random Access Preamble transmission;
  • preambleTransMax-Msg1-Repetition: the maximum number of Random Access Preamble transmissions with a given Msg1 repetition number before switching to Msg1 repetition with the next available higher Msg1 repetition number;
  • ssb-perRACH-OccasionAndCB-PreamblesPerSSB: defines the number of SSBs mapped to each PRACH occasion for 4-step RA type and the number of contention-based Random Access Preambles mapped to each SSB;
  • msgA-CB-PreamblesPerSSB-PerSharedRO: defines the number of contention-based Random Access Preambles for 2-step RA type mapped to each SSB when the PRACH occasions are shared between 2-step and 4-step RA types;
  • msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB: defines the number of SSBs mapped to each PRACH occasion for 2-step RA type and the number of contention-based Random Access Preambles mapped to each SSB;
  • numberOfPreamblesPerSSB-ForThisPartition: defines the number of consecutive preambles for a feature or a combination of features mapped to each SSB;
  • msgA-PUSCH-ResourceGroupA: defines MSGA PUSCH resources that the UE shall use when performing MSGA transmission using Random Access Preambles group A;
  • msgA-PUSCH-ResourceGroupB: defines MSGA PUSCH resources that the UE shall use when performing MSGA transmission using Random Access Preambles group B;
  • msgA-PUSCH-Resource-Index: identifies the index of the PUSCH resource used for MSGA in case of contention-free Random Access with 2-step RA type;
  • if groupBconfigured is configured, then Random Access Preambles group B is configured for 4-step RA type.
    • Amongst the contention-based Random Access Preambles associated with an SSB (as defined in TS 38.213), the first numberOfRA-PreamblesGroupA included in groupBconfigured Random Access Preambles belong to Random Access Preambles group A. The remaining Random Access Preambles associated with the SSB belong to Random Access Preambles group B (if configured).
  • if groupB-ConfiguredTwoStepRA is configured, then Random Access Preambles group B is configured for 2-step RA type.
    • Amongst the contention-based Random Access Preambles for 2-step RA type associated with an SSB (as defined in TS 38.213), the first numberOfRA-PreamblesGroupA included in GroupB-ConfiguredTwoStepRA Random Access Preambles belong to Random Access Preambles group A. The remaining Random Access Preambles associated with the SSB belong to Random Access Preambles group B (if configured).
  • if Random Access Preambles group B is configured for 4-step RA type:
    • ra-Msg3SizeGroupA: the threshold to determine the groups of Random Access Preambles for 4-step RA type;
    • msg3-DeltaPreamble: ΔPREAMBLE_Msg3 in TS 38.213;
    • messagePowerOffsetGroupB: the power offset for preamble selection included in groupBconfigured;
    • numberOfRA-PreamblesGroupA: defines the number of Random Access Preambles in Random Access Preamble group A for each SSB included in groupBconfigured.
  • if Random Access Preambles group B is configured for 2-step RA type:
    • msgA-DeltaPreamble: ΔMsgA_PUSCH in TS 38.213;
    • messagePowerOffsetGroupB: the power offset for preamble selection included in GroupB-ConfiguredTwoStepRA;
    • numberOfRA-PreamblesGroupA: defines the number of Random Access Preambles in Random Access Preamble group A for each SSB included in GroupB-ConfiguredTwoStepRA;
    • ra-MsgA-SizeGroupA: the threshold to determine the groups of Random Access Preambles for 2-step RA type.
  • the set of Random Access Preambles and/or PRACH occasions for SI request, if any;
  • the set of Random Access Preambles and/or PRACH occasions for beam failure recovery request, if any;
  • the set of Random Access Preambles and/or PRACH occasions for reconfiguration with sync, if any;
  • ra-ResponseWindow: the time window to monitor RA response(s) (SpCell only);
  • ra-ContentionResolutionTimer: the Contention Resolution Timer (SpCell only);
  • msgB-ResponseWindow: the time window to monitor RA response(s) for 2-step RA type (SpCell only).
In addition, the following information for related Serving Cell is assumed to be available for UEs:
  • if Random Access Preambles group B is configured:
The following UE variables are used for the Random Access procedure:
  • PREAMBLE_INDEX;
  • PREAMBLE_TRANSMISSION_COUNTER;
  • PREAMBLE_POWER_RAMPING_COUNTER;
  • PREAMBLE_POWER_RAMPING_STEP;
  • PREAMBLE_RECEIVED_TARGET_POWER;
  • PREAMBLE_BACKOFF;
  • PCMAX;
  • SCALING_FACTOR_BI;
  • TEMPORARY_C-RNTI;
  • RA_TYPE;
  • POWER_OFFSET_2STEP_RA;
  • MSGA_PREAMBLE_POWER_RAMPING_STEP.
When the Random Access procedure is initiated on a Serving Cell or to an LTM candidate cell, the MAC entity shall:
1 >
flush the Msg3 buffer;
1 >
flush the MSGA buffer;
1 >
set the PREAMBLE_TRANSMISSION_COUNTER to 1;
1 >
if the Random Access procedure is initiated on a Serving Cell; or
1 >
if the Random Access procedure is initiated by the PDCCH order to an LTM candidate cell and the PDCCH order indicates preamble initial transmission; or
1 >
if the Random Access procedure is initiated by the PDCCH order to an LTM candidate cell, which is different from the LTM candidate cell to perform the last Random Access Preamble transmission initiated by the PDCCH order to an LTM candidate cell, and the PDCCH order indicates preamble re-transmission:
2 >
set the PREAMBLE_POWER_RAMPING_COUNTER to 1;
1 >
set the PREAMBLE_BACKOFF to 0 ms;
1 >
set POWER_OFFSET_2STEP_RA to 0 dB;
1 >
if the carrier to use for the Random Access procedure is explicitly signalled:
2 >
select the signalled carrier for performing Random Access procedure;
2 >
set the PCMAX to PCMAX,f,c of the signalled carrier.
1 >
else if the carrier to use for the Random Access procedure is not explicitly signalled; and
1 >
if the Serving Cell for the Random Access procedure is configured with supplementary uplink as specified in TS 38.331; and
1 >
if the RSRP of the downlink pathloss reference is less than rsrp-ThresholdSSB-SUL:
2 >
select the SUL carrier for performing Random Access procedure;
2 >
set the PCMAX to PCMAX,f,c of the SUL carrier.
1 >
else:
2 >
select the NUL carrier for performing Random Access procedure;
2 >
set the PCMAX to PCMAX,f,c of the NUL carrier.
1 >
perform the BWP operation as specified in clause 5.15, except when the Random Access procedure is initiated by the PDCCH order to an LTM candidate cell;
1 >
select the set of Random Access resources applicable to the current Random Access procedure according to clause 5.1.1b;
1 >
if the Random Access procedure is initiated by PDCCH order and if the ra-PreambleIndex explicitly provided by PDCCH is not 0b000000; or
1 >
if the Random Access procedure was initiated for SI request (as specified in TS 38.331) and the Random Access Resources for SI request have been explicitly provided by RRC; or
1 >
if the Random Access procedure was initiated for SpCell beam failure recovery (as specified in clause 5.17) and if the contention-free Random Access Resources for beam failure recovery request for 4-step RA type have been explicitly provided by RRC for the BWP selected for Random Access procedure; or
1 >
if the Random Access procedure was initiated for reconfiguration with sync and if the contention-free Random Access Resources for 4-step RA type have been explicitly provided in rach-ConfigDedicated for the BWP selected for Random Access procedure; or
1 >
if the Random Access procedure was initiated for LTM cell switch and if the contention-free Random Access Resources have been explicitly provided in LTM Cell Switch Command MAC CE:
2 >
set the RA_TYPE to 4-stepRA.
1 >
else if the BWP selected for Random Access procedure is configured with both 2-step and 4-step RA type Random Access Resources within the selected set of Random Access resources (as specified in clause 5.1.1b) and the RSRP of the downlink pathloss reference is above msgA-RSRP-Threshold; or
1 >
if the BWP selected for Random Access procedure is only configured with 2-step RA type Random Access resources within the selected set of Random Access resources according to clause 5.1.1b; or
1 >
if the Random Access procedure was initiated for reconfiguration with sync and if the contention-free Random Access Resources for 2-step RA type have been explicitly provided in rach-ConfigDedicated for the BWP selected for Random Access procedure:
2 >
set the RA_TYPE to 2-stepRA.
1 >
else:
2 >
set the RA_TYPE to 4-stepRA.
1 >
perform initialization of variables specific to Random Access type as specified in clause 5.1.1a;
1 >
if RA_TYPE is set to 2-stepRA:
2 >
perform the Random Access Resource selection procedure for 2-step RA type (see clause 5.1.2a).
1 >
else:
2 >
perform the Random Access Resource selection procedure (see clause 5.1.2).
Up

5.1.1a  Initialization of variables specific to Random Access type |R16|  p. 24

The MAC entity shall:
1 >
if RA_TYPE is set to 2-stepRA:
2 >
set PREAMBLE_POWER_RAMPING_STEP to msgA-PreamblePowerRampingStep;
2 >
set SCALING_FACTOR_BI to 1;
2 >
apply preambleTransMax included in the RACH-ConfigGenericTwoStepRA;
2 >
if the Random Access procedure was initiated for reconfiguration with sync or for SCG activation; and
2 >
if cfra-TwoStep is configured for the selected carrier:
3 >
if msgA-TransMax is configured in the cfra-TwoStep:
4 >
apply msgA-TransMax configured in the cfra-TwoStep.
2 >
else if msgA-TransMax is included in the RACH-ConfigCommonTwoStepRA:
3 >
apply msgA-TransMax included in the RACH-ConfigCommonTwoStepRA.
2 >
if the Random Access procedure was initiated for SpCell beam failure recovery (as specified in clause 5.17); and
2 >
if beamFailureRecoveryConfig is configured for the active UL BWP of the selected carrier; and
2 >
if ra-PrioritizationTwoStep is configured in the beamFailureRecoveryConfig:
3 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority included in the ra-PrioritizationTwoStep in beamFailureRecoveryConfig;
3 >
if scalingFactorBI is configured in the ra-PrioritizationTwoStep in beamFailureRecoveryConfig:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if the Random Access procedure was initiated for reconfiguration with sync or for SCG activation; and
2 >
if rach-ConfigDedicated is configured for the selected carrier; and
2 >
if ra-PrioritizationTwoStep is configured in the rach-ConfigDedicated:
3 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority included in the ra-PrioritizationTwoStep in rach-ConfigDedicated;
3 >
if scalingFactorBI is configured in ra-PrioritizationTwoStep in the rach-ConfigDedicated:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if both ra-PrioritizationForSlicingTwoStep for a NSAG-ID and ra-PrioritizationForAccessIdentityTwoStep are configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with both this NSAG-ID and Access Identity 1 or 2; and
2 >
if for at least one of these Access Identities the corresponding bit in the ra-PrioritizationForAI is set to one:
3 >
if enableRA-PrioritizationForSlicing is set to true:
4 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForSlicingTwoStep for this NSAG-ID:
5 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
4 >
if scalingFactorBI is configured in the ra-PrioritizationForSlicingTwoStep for this NSAG-ID:
5 >
set SCALING_FACTOR_BI to the scalingFactorBI.
3 >
else if enableRA-PrioritizationForSlicing is set to false:
4 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForAccessIdentityTwoStep:
5 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
4 >
if scalingFactorBI is configured in the ra-PrioritizationForAccessIdentityTwoStep:
5 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if ra-PrioritizationForSlicingTwoStep for a NSAG-ID is configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with this NSAG-ID:
3 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForSlicingTwoStep for this NSAG-ID:
4 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
3 >
if scalingFactorBI is configured in the ra-PrioritizationForSlicingTwoStep for this NSAG-ID:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if ra-PrioritizationForAccessIdentityTwoStep is configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with Access Identity 1 or 2; and
2 >
if for at least one of these Access Identities the corresponding bit in the ra-PrioritizationForAI is set to one:
3 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForAccessIdentityTwoStep:
4 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
3 >
if scalingFactorBI is configured in the ra-PrioritizationForAccessIdentityTwoStep:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
set MSGA_PREAMBLE_POWER_RAMPING_STEP to PREAMBLE_POWER_RAMPING_STEP.
1 >
else (i.e. RA_TYPE is set to 4-stepRA):
2 >
set PREAMBLE_POWER_RAMPING_STEP to powerRampingStep;
2 >
set SCALING_FACTOR_BI to 1;
2 >
set preambleTransMax to preambleTransMax included in the RACH-ConfigGeneric;
2 >
if the Random Access procedure was initiated for SpCell beam failure recovery (as specified in clause 5.17); and
2 >
if beamFailureRecoveryConfig is configured for the active UL BWP of the selected carrier:
3 >
start the beamFailureRecoveryTimer, if configured;
3 >
apply the parameters powerRampingStep, preambleReceivedTargetPower, and preambleTransMax configured in the beamFailureRecoveryConfig.
2 >
if the Random Access procedure was initiated for beam failure recovery (as specified in clause 5.17); and
2 >
if beamFailureRecoveryConfig is configured for the active UL BWP of the selected carrier; and
2 >
if ra-Prioritization is configured in the beamFailureRecoveryConfig:
3 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority included in the ra-Prioritization in beamFailureRecoveryConfig;
3 >
if scalingFactorBI is configured in ra-Prioritization in the beamFailureRecoveryConfig:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if the Random Access procedure was initiated for reconfiguration with sync or for SCG activation; and
2 >
if rach-ConfigDedicated is configured for the selected carrier; and
2 >
if ra-Prioritization is configured in the rach-ConfigDedicated:
3 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority included in the ra-Prioritization in rach-ConfigDedicated;
3 >
if scalingFactorBI is configured in ra-Prioritization in the rach-ConfigDedicated:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if both ra-PrioritizationForSlicing for a NSAG-ID and ra-PrioritizationForAccessIdentity are configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with both this NSAG-ID and Access Identity 1 or 2; and
2 >
if for at least one of these Access Identities the corresponding bit in the ra-PrioritizationForAI is set to one:
3 >
if enableRA-PrioritizationForSlicing is set to true:
4 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForSlicing for this NSAG-ID:
5 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
4 >
if scalingFactorBI is configured in the ra-PrioritizationForSlicing for this NSAG-ID:
5 >
set SCALING_FACTOR_BI to the scalingFactorBI.
3 >
else if enableRA-PrioritizationForSlicing is set to false:
4 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForAccessIdentity:
5 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
4 >
if scalingFactorBI is configured in the ra-PrioritizationForAccessIdentity:
5 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if ra-PrioritizationForSlicing for a NSAG-ID is configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with this NSAG-ID:
3 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForSlicing for this NSAG-ID:
4 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
3 >
if scalingFactorBI is configured in the ra-PrioritizationForSlicing for this NSAG-ID:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
else if ra-PrioritizationForAccessIdentity is configured for the selected carrier; and
2 >
if the MAC entity is provided by upper layers with Access Identity 1 or 2; and
2 >
if for at least one of these Access Identities the corresponding bit in the ra-PrioritizationForAI is set to one:
3 >
if powerRampingStepHighPriority is configured in the ra-PrioritizationForAccessIdentity:
4 >
set PREAMBLE_POWER_RAMPING_STEP to the powerRampingStepHighPriority.
3 >
if scalingFactorBI is configured in the ra-PrioritizationForAccessIdentity:
4 >
set SCALING_FACTOR_BI to the scalingFactorBI.
2 >
if RA_TYPE is switched from 2-stepRA to 4-stepRA during this Random Access procedure:
3 >
set POWER_OFFSET_2STEP_RA to (PREAMBLE_POWER_RAMPING_COUNTER - 1) × (MSGA_PREAMBLE_POWER_RAMPING_STEP - PREAMBLE_POWER_RAMPING_STEP).
Up

5.1.1b  Selection of the set of Random Access resources for the Random Access procedure |R17|  p. 27

The MAC entity shall:
1 >
if the BWP selected for Random Access procedure is configured with both set(s) of Random Access resources with msg3-Repetitions set to true and set(s) of Random Access resources without msg3-Repetitions set to true and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg3; or
1 >
if the BWP selected for Random Access procedure is only configured with the set(s) of Random Access resources with msg3-Repetitions set to true:
2 >
assume Msg3 repetition is applicable for the current Random Access procedure.
1 >
else:
2 >
assume Msg3 repetition is not applicable for the current Random Access procedure.
1 >
if contention-free Random Access Resources have been provided for this Random Access procedure and a Msg1 repetition number is indicated in rach-ConfigDedicated:
2 >
assume Msg1 repetition is applicable and Msg1 repetition number applicable for the current Random Access procedure is the Msg1 repetition number indicated in rach-ConfigDedicated.
1 >
else if contention free Random Access Resources have not been provided for this Random Access procedure and the BWP selected for the Random Access procedure is configured with set(s) of Random Access resources with msg1-Repetitions set to true and set(s) of Random Access resources without msg1-Repetitions set to true:
2 >
if the BWP selected for the Random Access procedure is configured with set(s) of Random Access resources associated with Msg1 repetition number 8 and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum8:
3 >
assume Msg1 repetition is applicable and Msg1 repetition number applicable for the current Random Access procedure includes 8.
2 >
if the BWP selected for the Random Access procedure is configured with set(s) of Random Access resources associated with Msg1 repetition number 4 and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum4:
3 >
assume Msg1 repetition is applicable and Msg1 repetition number applicable for the current Random Access procedure includes 4.
2 >
if the BWP selected for the Random Access procedure is configured with set(s) of Random Access resources associated with Msg1 repetition number 2 and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum2:
3 >
assume Msg1 repetition is applicable and Msg1 repetition number applicable for the current Random Access procedure includes 2.
2 >
else if the RSRP of the downlink pathloss reference is not less than any configured rsrp-ThresholdMsg1-RepetitionNumX:
3 >
assume Msg1 repetition is not applicable for the current Random Access procedure.
1 >
else if the BWP selected for Random Access procedure is configured only with Random Access resources with msg1-Repetitions set to true:
2 >
assume Msg1 repetition is applicable for the current Random Access procedure;
2 >
if at least one of rsrp-ThresholdMsg1-RepetitionNumX is configured:
3 >
if rsrp-ThresholdMsg1-RepetitionNum8 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum8;
4 >
assume Msg1 repetition number applicable for the current Random Access procedure includes 8.
3 >
if rsrp-ThresholdMsg1-RepetitionNum4 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum4:
4 >
assume Msg1 repetition number applicable for the current Random Access procedure includes 4.
3 >
if rsrp-ThresholdMsg1-RepetitionNum2 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum2:
4 >
assume Msg1 repetition number applicable for the current Random Access procedure includes 2.
3 >
else if the RSRP of the downlink pathloss reference is not less than any configured rsrp-ThresholdMsg1-RepetitionNumX:
4 >
assume Msg1 repetition number applicable for the current Random Access procedure is the lowest Msg1 repetition number configured for this BWP.
2 >
else (none of rsrp-ThresholdMsg1-RepetitionNumX is configured):
3 >
assume Msg1 repetition number applicable for the current Random Access procedure is the Msg1 repetition number that configured for this BWP.
1 >
if neither contention-free Random Access Resources nor Random Access Resources for SI request have been provided for this Random Access procedure and one or more of the features including (e)RedCap and/or Slicing and/or SDT and/or MSG3 repetition and/or MSG1 repetition is applicable for this Random Access procedure:
2 >
if none of the sets of Random Access resources are available for any feature applicable to the current Random Access procedure (as specified in clause 5.1.1c):
3 >
select the set(s) of Random Access resources that are not associated with any feature indication (as specified in clause 5.1.1c) for this Random Access procedure.
2 >
else if there is one set of Random Access resources available which can be used for indicating all features triggering this Random Access procedure:
3 >
select this set of Random Access resources for this Random Access procedure.
2 >
else if there are more than one set of Random Access resources available which can be used for indicating all features triggering this Random Access procedure and Msg1 repetition is applicable for this Random Access procedure:
3 >
select the set of Random Access resources that associated with highest repetition number among the sets of Random Access resources.
2 >
else (i.e. there are one or more sets of Random Access resources available that are configured with indication(s) for a subset of all features triggering this Random Access procedure):
3 >
select a set of Random Access resources from the available set(s) of Random Access resources based on the priority order indicated by upper layers as specified in clause 5.1.1d for this Random Access Procedure.
1 >
else if contention-free Random Access Resources with Msg1 repetition have been provided for this Random Access procedure and Msg1 repetition number is indicated in rach-ConfigDedicated, and RedCap is applicable for the current Random Access procedure:
2 >
select the set of Random Access resources that is only configured with RedCap indication and Msg1 repetition indication and associated with the indicated Msg1 repetition number for this Random Access procedure.
1 >
else if contention-free Random Access Resources have been provided for this Random Access procedure and RedCap is applicable for the current Random Access procedure and there is one set of Random Access resources available that is only configured with RedCap indication; or
1 >
else if contention-free Random Access Resources have been provided for this Random Access procedure and eRedCap is applicable for the current Random Access procedure and there is one set of Random Access resources available that is only configured with eRedCap indication; or
1 >
else if contention-free Random Access Resources have been provided for this Random Access procedure and eRedCap is applicable for the current Random Access procedure and there is no set of Random Access resources available that is only configured with eRedCap indication and there is one set of Random Access resources available that is only configured with RedCap indication:
2 >
select this set of Random Access resources for this Random Access procedure.
1 >
else:
2 >
if the Random Access procedure is initiated by PDCCH order with DCI PRACH association indicator field set to 1 and SSB-MTC-AdditionalPCI is configured by upper layers, as specified in clause 7.3.1.2.1 of TS 38.212:
3 >
select the set of Random Access resources corresponding to the active additionalPCI.
2 >
else if contention-free Random Access Resources with Msg1 repetition have been provided for this Random Access procedure, and Msg1 repetition number is indicated in rach-ConfigDedicated:
3 >
select the set of Random Access resources that is only configured with Msg1 repetition indication and associated with the indicated Msg1 repetition number for this Random Access procedure.
2 >
else if the Random Access procedure was initiated for SI request and Random Access Resources associated with Msg1 repetition for SI request and Msg1 repetition number have been provided for this Random Access procedure:
3 >
select the set of Random Access resources that is only configured with Msg1 repetition indication and associated with the indicated Msg1 repetition number for this Random Access procedure.
2 >
else:
3 >
select the set of Random Access resources that are not associated with any feature indication (as specified in clause 5.1.1c) for the current Random Access procedure.
Up

5.1.1c  Availability of the set of Random Access resources |R17|  p. 30

The MAC entity shall for each set of configured Random Access resources for 4-step RA type and for each set of configured Random Access resources for 2-step RA type:
1 >
if eRedCap is set to true for a set of Random Access resources:
2 >
consider the set of Random Access resources as not available for a Random Access procedure for which eRedCap is not applicable.
1 >
if redCap is set to true for a set of Random Access resources configured for 4-step RA type, but not for 2-step RA type:
2 >
consider the set of Random Access resources as not available for a Random Access procedure for which RedCap is not applicable.
1 >
if redCap is set to true for a set of Random Access resources configured for 2-step RA type regardless of whether it is also configured for 4-step RA type:
2 >
consider the set of Random Access resources as not available for a Random Access procedure for which (e)RedCap is not applicable;
2 >
consider eRedCap as both eRedCap and RedCap in the following procedure in clause 5.1.1c and 5.1.1d.
1 >
if smallData is set to true for a set of Random Access resources:
2 >
consider the set of Random Access resources as not available for the Random Access procedure which is not triggered for RA-SDT by MO-SDT as specified in TS 38.331.
1 >
if NSAG-List is configured for a set of Random Access resources:
2 >
consider the set of Random Access resources as not available for the Random Access procedure unless it is triggered for any one of the NSAG-ID(s) in the NSAG-List.
1 >
if msg3-Repetitions is set to true for a set of Random Access resources:
2 >
consider the set of Random Access resources as not available for the Random Access procedure if Msg3 repetition is not applicable.
1 >
if msg1-Repetitions is set to true for a set of Random Access resources:
2 >
if Msg1 repetition is not applicable to the current Random Access procedure; or
2 >
if the set of Random Access resources is not associated with any of the Msg1 repetition number that is applicable to the current Random Access procedure:
3 >
consider the set of Random Access resources as not available for the Random Access procedure.
1 >
if a set of Random Access resources is not configured with FeatureCombination:
2 >
consider the set of Random Access resources to not associated with any feature.
Up

5.1.1d  Selection of the set of Random Access resources based on feature prioritization |R17|  p. 31

The MAC entity shall:
1 >
among the available sets of Random Access resources for this Random Access procedure (as specified in clause 5.1.1c), identify those configured with a feature which has the highest priority assigned in featurePriorities among all the features applicable to this Random Access procedure as specified in TS 38.331.
1 >
if a single set of Random Access resources is identified:
2 >
select this set of Random Access resources.
1 >
else if more than one set of Random Access resources is identified:
2 >
if all the identified sets of Random Access resources are configured with Msg1 repetition indication and the same featureCombination:
3 >
select the set of Random Access resources that associated with highest Msg1 repetition number among the identified sets of Random Access resources.
2 >
else:
3 >
repeat the procedure taking as an input the identified sets of Random Access resources and the feature applicable to the current Random Access procedure with the highest priority assigned in featurePriorities among all the features applicable to this Random Access procedure, except the features considered already.
1 >
else (i.e. no set of Random Access resources is identified):
2 >
repeat the procedure taking as an input the previous identified available sets of Random Access resources and the feature applicable to the current Random Access procedure with the highest priority assigned in featurePriorities among all the features applicable to this Random Access procedure, except the features considered already.
Up

5.1.1e  Selection of Msg1 repetition for SI request |R18|  p. 31

The MAC entity shall:
1 >
if si-RequestResourcesRepetitionNum8 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum8:
2 >
criteria to apply Msg1 repetition for SI request is considered met and Msg1 repetition number applicable is 8.
1 >
else if si-RequestResourcesRepetitionNum4 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum4:
2 >
criteria to apply Msg1 repetition for SI request is considered met and Msg1 repetition number applicable is 4.
1 >
else si-RequestResourcesRepetitionNum2 is configured and the RSRP of the downlink pathloss reference is less than rsrp-ThresholdMsg1-RepetitionNum2:
2 >
criteria to apply Msg1 repetition for SI request is considered met and Msg1 repetition number applicable is 2.
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