ReferenceTimeInfo (ReferenceTimeInfo-r16)
ReferenceTimeInfo-r16 is an RRC information element of 3GPP TS 38.331 (38331), the 5G NR Radio Resource Control (RRC) protocol.
Definition
The IE ReferenceTimeInfo contains timing information for 5G internal system clock used for, e.g., time stamping, see TS 23.501 [32], clause 5.27.1.2.
ReferenceTimeInfo-r16 ::= SEQUENCE {
time-r16 ReferenceTime-r16,
uncertainty-r16 INTEGER (0..32767) OPTIONAL, -- Need S
timeInfoType-r16 ENUMERATED {localClock} OPTIONAL, -- Need S
referenceSFN-r16 INTEGER (0..1023) OPTIONAL -- Cond RefTime
}Candidate change requests of v16.1.0
The CRs whose title or cover names this change, strong and likely matches only.
- CR 1641 (strong): Correction of NR IIoT
Fields (4)
| Field | Description |
|---|---|
| time-r16 ReferenceTime-r16 | This field indicates time reference with 10ns granularity. If included in DLInformationTransfer and if UE-side TA PDC is de-activated, the indicated time may not be referenced at the network, i.e., gNB may pre-compensate for RF propagation delay. If included in DLInformationTransfer and if UE is requested to transmit UE Rx-Tx time difference measurement, the indicated time may not be referenced at the network, i.e., gNB may pre-compensate for RF propagation delay. Otherwise, the indicated time is referenced at the network, i.e., without compensating for RF propagation delay. In an NTN cell, the indicated time is referenced at the uplink time synchronization reference point (RP), i.e., UE should take into account the propagation delay between UE and RP when determining the UTC time at the UE. The indicated time in 10ns unit from the origin is refDays 864001000100000 + refSeconds 1000100000 + refMilliSeconds 100000 + refTenNanoSeconds . The refDays field specifies the sequential number of days (with day count starting at 0) from the origin of the time field. If the referenceTimeInfo field is received in DLInformationTransfer message, the time field indicates the time at the ending boundary of the system frame indicated by referenceSFN . The UE considers this frame (indicated by referenceSFN ) to be the frame which is nearest to the frame where the message is received (which can be either in the past or in the future). If the referenceTimeInfo field is received in SIB9 , the time field indicates the time at the SFN boundary at or immediately after the ending boundary of the SI-window in which SIB9 is transmitted. If referenceTimeInfo field is received in SIB9 , this field is excluded when determining changes in system information, i.e. changes of time should neither result in system information change notifications nor in a modification of valueTag in SIB1 . NOTE: The estimated time in an NTN-cell may be less accurate than the estimated time in a TN-cell. |
| uncertainty-r16 INTEGER (0..32767) · OPTIONAL Need S | This field indicates the uncertainty of the reference time information provided by the time field. The uncertainty is 25ns multiplied by this field . If this field is absent, the uncertainty is unspecified. |
| timeInfoType-r16 ENUMERATED {localClock} · OPTIONAL Need S | If timeInfoType is not included, the time indicates the GPS time and the origin of the time field is 00:00:00 on Gregorian calendar date 6 January, 1980 (start of GPS time). If timeInfoType is set to localClock , the origin of the time is unspecified. |
| referenceSFN-r16 INTEGER (0..1023) · OPTIONAL Cond RefTime | This field indicates the reference SFN corresponding to the reference time information. If referenceTimeInfo field is received in DLInformationTransfer message, this field indicates the SFN of PCell. |