LTM-CSI-ReportConfig (LTM-CSI-ReportConfig-r18)

RRC IE · TS 38.331 v19.4.0 (2026-09) · clause 6.3.2

LTM-CSI-ReportConfig-r18 is an RRC information element of 3GPP TS 38.331 (38331), the 5G NR Radio Resource Control (RRC) protocol.

First seen v18.0.0 (2024-01) · Last changed v19.1.0 (2026-01)

Definition

The IE LTM-CSI-ReportConfig is used to configure gNB-scheduled measurement report on the cell in which the LTM-CSI-ReportConfig is included when the field ltm-ReportConfigType is configured as periodic , semi-persistentOnPUCCH , or semi-persistentOnPUSCH/aperiodic .

LTM-CSI-ReportConfig-r18 ::=      SEQUENCE {
    ltm-CSI-ReportConfigId-r18                     LTM-CSI-ReportConfigId-r18,
    ltm-ResourcesForChannelMeasurement-r18         LTM-CSI-ResourceConfigId-r18,
    ltm-ReportConfigType-r18                           CHOICE {
        periodic-r18                                       SEQUENCE {
            reportSlotConfig-r18                               CSI-ReportPeriodicityAndOffset,
            pucch-CSI-ResourceList-r18                         SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource
        },
        semiPersistentOnPUCCH-r18                          SEQUENCE {
            reportSlotConfig-r18                               CSI-ReportPeriodicityAndOffset,
            pucch-CSI-ResourceList-r18                         SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource
        },
        semiPersistentOnPUSCH-r18                          SEQUENCE {
            reportSlotConfig-r18                               CSI-ReportPeriodicityAndOffset,
            reportSlotOffsetList-r18                           SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128),
            reportSlotOffsetListDCI-0-2-r18                    SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128),
            reportSlotOffsetListDCI-0-1-r18                    SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128),
            p0alpha-r18                                        P0-PUSCH-AlphaSetId
        },
        aperiodic-r18                                      SEQUENCE {
            reportSlotOffsetList-r18                           SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128),
            reportSlotOffsetListDCI-0-2-r18                    SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128),
            reportSlotOffsetListDCI-0-1-r18                    SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)
        },
        ...,
        eventTriggered-r19                         SEQUENCE {
            eventId-r19                                CHOICE {
                eventLTM2-r19                              SEQUENCE {
                    ltm2-Threshold-r19                         MeasTriggerQuantity,
                    hysteresis-r19                             Hysteresis,
                    timeToTrigger-r19                          TimeToTrigger,
                    ...
                },
                eventLTM3-r19                              SEQUENCE {
                    ltm3-Offset-r19                            MeasTriggerQuantityOffset,
                    hysteresis-r19                             Hysteresis,
                    timeToTrigger-r19                          TimeToTrigger,
                    servingSpecificOffsetS-r19                 MeasTriggerQuantityOffset                      OPTIONAL, -- Need S
                    ...
                },
                eventLTM4-r19                              SEQUENCE {
                    ltm4-Threshold-r19                         MeasTriggerQuantity,
                    hysteresis-r19                             Hysteresis,
                    timeToTrigger-r19                          TimeToTrigger,
                    ...
                },
                eventLTM5-r19                              SEQUENCE {
                    ltm5-Threshold1-r19                        MeasTriggerQuantity,
                    ltm5-Threshold2-r19                        MeasTriggerQuantity,
                    hysteresis-r19                             Hysteresis,
                    timeToTrigger-r19                          TimeToTrigger,
                    ...
                },
                ...
            },
            eventTriggeredReportConfig-r19             SEQUENCE {
                ltm-CandidateReportConfigList-r19          SEQUENCE (SIZE (1..maxNrofLTM-Configs-r18)) OF LTM-CandidateReportConfig-r19
                OPTIONAL, -- Need R
                ltm-EventTriggeredReportContent-r19            LTM-EventTriggeredReportContent-r19            OPTIONAL, -- Need R
                reportOnLeave-r19                              ENUMERATED {enabled}                           OPTIONAL, -- Need R
                ltm-EventTriggeredPeriodicReport-r19           LTM-EventTriggeredPeriodicReport-r19           OPTIONAL  -- Need S
            }                                                                                                 OPTIONAL, -- Need R
            ...
        }
    },
    ltm-ReportContent-r18                          LTM-ReportContent-r18,
    ...,
    [[
        ltm-ReportContent-v1900                        LTM-ReportContent-v1900                                    OPTIONAL, -- Need R
        ltm-EarlyCSI-ReportConfig-r19                  LTM-EarlyCSI-ReportConfig-r19                              OPTIONAL  -- Cond EarlyCSI
    ]]
}

Candidate change requests of v19.1.0

The CRs whose title or cover names this change, strong and likely matches only.

CR 5587 r1 (likely): Introduction of early CSI acquisition for L3 handover [EarlyCSI_L3HO]

Fields (47)

Field	Description
ltm-CSI-ReportConfigId-r18 LTM-CSI-ReportConfigId-r18
ltm-ResourcesForChannelMeasurement-r18 LTM-CSI-ResourceConfigId-r18	This field indicates the index of SSB or CSI-RS in the field LTM-CSI-ResourceConfig .
ltm-ReportConfigType-r18 CHOICE {	This field specifies how the UE shall report the measurement results for LTM either by gNB-scheduled measurement report or by event-triggered measurement report by MAC CE, or to configure execution conditions for LTM. The UE shall ignore this field if LTM-CSI-ReportConfig is configured in a LTM-Candidate IE. The value eventTriggered can only be configured in the SpCell.
periodic-r18 SEQUENCE {
reportSlotConfig-r18 CSI-ReportPeriodicityAndOffset	Periodicity and slot offset (see TS 38.214 [19], clause 5.2.1.4). The UE shall ignore the offset provided by this field in case semiPersistentOnPUSCH is configured.
pucch-CSI-ResourceList-r18 SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource
semiPersistentOnPUCCH-r18 SEQUENCE {
reportSlotConfig-r18 CSI-ReportPeriodicityAndOffset	Periodicity and slot offset (see TS 38.214 [19], clause 5.2.1.4). The UE shall ignore the offset provided by this field in case semiPersistentOnPUSCH is configured.
pucch-CSI-ResourceList-r18 SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource
semiPersistentOnPUSCH-r18 SEQUENCE {
reportSlotConfig-r18 CSI-ReportPeriodicityAndOffset	Periodicity and slot offset (see TS 38.214 [19], clause 5.2.1.4). The UE shall ignore the offset provided by this field in case semiPersistentOnPUSCH is configured.
reportSlotOffsetList-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
reportSlotOffsetListDCI-0-2-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
reportSlotOffsetListDCI-0-1-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
p0alpha-r18 P0-PUSCH-AlphaSetId since v18.5.0
aperiodic-r18 SEQUENCE {
reportSlotOffsetList-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
reportSlotOffsetListDCI-0-2-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
reportSlotOffsetListDCI-0-1-r18 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER (0..128)	Timing offset Y for semi persistent reporting using PUSCH and aperiodic reporting.
eventTriggered-r19 SEQUENCE { since v19.0.0	For CLTM execution conditions, network can only configure events eventLTM3 and eventLTM5 .
eventId-r19 CHOICE { since v19.0.0	Type of LTM event for triggering event-triggered measurement report as specified in TS 38.321 [3].
eventLTM2-r19 SEQUENCE { since v19.0.0
ltm2-Threshold-r19 MeasTriggerQuantity since v19.0.0	Thresholds defined in the entering/leaving conditions for different LTM events.
hysteresis-r19 Hysteresis since v19.0.0	Hysteresis when evaluating the entering/leaving conditions for an LTM event.
timeToTrigger-r19 TimeToTrigger since v19.0.0
eventLTM3-r19 SEQUENCE { since v19.0.0
ltm3-Offset-r19 MeasTriggerQuantityOffset since v19.0.0	Offset for the entering/leaving condition for event LTM3. The actual value is field value 0.5 dB.
hysteresis-r19 Hysteresis since v19.0.0	Hysteresis when evaluating the entering/leaving conditions for an LTM event.
timeToTrigger-r19 TimeToTrigger since v19.0.0
servingSpecificOffsetS-r19 MeasTriggerQuantityOffset · OPTIONAL Need S since v19.1.0	Offset for event condition that is applicable for all the reference signals belonging to serving cell. If the field is absent, the value '0dB' is applied.
eventLTM4-r19 SEQUENCE { since v19.0.0
ltm4-Threshold-r19 MeasTriggerQuantity since v19.0.0	Thresholds defined in the entering/leaving conditions for different LTM events.
hysteresis-r19 Hysteresis since v19.0.0	Hysteresis when evaluating the entering/leaving conditions for an LTM event.
timeToTrigger-r19 TimeToTrigger since v19.0.0
eventLTM5-r19 SEQUENCE { since v19.0.0
ltm5-Threshold1-r19 MeasTriggerQuantity since v19.0.0	Thresholds defined in the entering/leaving conditions for different LTM events.
ltm5-Threshold2-r19 MeasTriggerQuantity since v19.0.0	Thresholds defined in the entering/leaving conditions for different LTM events.
hysteresis-r19 Hysteresis since v19.0.0	Hysteresis when evaluating the entering/leaving conditions for an LTM event.
timeToTrigger-r19 TimeToTrigger since v19.0.0
eventTriggeredReportConfig-r19 SEQUENCE { · OPTIONAL Need R since v19.1.0	If this field is included, the LTM-CSI-ReportConfig is for L1 measurement and event-triggered reporting as specified in TS 38.321 [3] clause 5.35. Otherwise, the LTM-CSI-ReportConfig is to configure execution conditions for LTM as specified in TS 38.321 [3] clause 5.36.
ltm-CandidateReportConfigList-r19 SEQUENCE (SIZE (1..maxNrofLTM-Configs-r18)) OF LTM-CandidateReportConfig-r19 · OPTIONAL Need R since v19.1.0	List of report configurations for LTM candidate IDs. If the field is absent the UE shall measure all the LTM candidate cells associated to the field ltm-ResourcesForChannelMeasurement.
ltm-EventTriggeredReportContent-r19 LTM-EventTriggeredReportContent-r19 · OPTIONAL Need R since v19.1.0	This field indicates what to include in a measurement report when an LTM event is triggered.
reportOnLeave-r19 ENUMERATED {enabled} · OPTIONAL Need R since v19.1.0	Indicates whether the event-triggered measurement report by MAC CE shall be triggered when leaving condition is satisfied, as specified in TS 38.321 [3].
ltm-EventTriggeredPeriodicReport-r19 LTM-EventTriggeredPeriodicReport-r19 · OPTIONAL Need S since v19.1.0	This field indicates when an LTM event is triggered, whether the event-triggered measurement report is sent periodically. If the field is absent, the event-triggered measurement report is sent once, as specified in TS 38.321 [3].
ltm-ReportContent-r18 LTM-ReportContent-r18	This field defines the content of the LTM L1 measurement report. The UE shall ignore ltm-ReportContent-r18 if the field ltm-ReportConfigType is set to eventTriggered or if the field ltm-EarlyCSI-ReportConfig is present.
ltm-ReportContent-v1900 LTM-ReportContent-v1900 · OPTIONAL Need R since v19.0.0	This field defines the content of the LTM L1 measurement report. The UE shall ignore ltm-ReportContent-r18 if the field ltm-ReportConfigType is set to eventTriggered or if the field ltm-EarlyCSI-ReportConfig is present.
ltm-EarlyCSI-ReportConfig-r19 LTM-EarlyCSI-ReportConfig-r19 · OPTIONAL Cond EarlyCSI since v19.1.0

LTM-CSI-ReportConfig (LTM-CSI-ReportConfig-r18)

Definition

Candidate change requests of v19.1.0

Fields (47)

Used by (2)

Uses (18)

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