For the purposes of the present document, the abbreviations given in
TR 21.905, in
TS 36.300 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
TR 21.905 and
TS 36.300.
5GC
5G Core Network
5GS
5G System
5QI
5G QoS Identifier
A-CSI
Aperiodic CSI
AGC
Automatic Gain Control
AKA
Authentication and Key Agreement
AMBR
Aggregate Maximum Bit Rate
AMC
Adaptive Modulation and Coding
AMF
Access and Mobility Management Function
ARP
Allocation and Retention Priority
BA
Bandwidth Adaptation
BCCH
Broadcast Control Channel
BCH
Broadcast Channel
BFD
Beam Failure Detection
BH
Backhaul
BL
Bandwidth reduced Low complexity
BPSK
Binary Phase Shift Keying
C-RNTI
Cell RNTI
CAG
Closed Access Group
CAPC
Channel Access Priority Class
CBRA
Contention Based Random Access
CCE
Control Channel Element
CD-SSB
Cell Defining SSB
CFR
Common Frequency Resource
CFRA
Contention Free Random Access
CG
Configured Grant
CHO
Conditional Handover
CIoT
Cellular Internet of Things
CLI
Cross Link interference
CMAS
Commercial Mobile Alert Service
CORESET
Control Resource Set
CP
Cyclic Prefix
CPA
Conditional PSCell Addition
CPC
Conditional PSCell Change
DAG
Directed Acyclic Graph
DAPS
Dual Active Protocol Stack
DFT
Discrete Fourier Transform
DCI
Downlink Control Information
DCP
DCI with CRC scrambled by PS-RNTI
DL-AoD
Downlink Angle-of-Departure
DL-SCH
Downlink Shared Channel
DL-TDOA
Downlink Time Difference Of Arrival
DMRS
Demodulation Reference Signal
DRX
Discontinuous Reception
E-CID
Enhanced Cell-ID (positioning method)
EHC
Ethernet Header Compression
ePWS
enhancements of Public Warning System
ETWS
Earthquake and Tsunami Warning System
FSA ID
Frequency Selection Area Identity
G-CS-RNTI
Group Configured Scheduling RNTI
G-RNTI
Group RNTI
FS
Feature Set
GFBR
Guaranteed Flow Bit Rate
GIN
Group ID for Network selection
GNSS
Global Navigation Satellite System
GSO
Geosynchronous Orbit
H-SFN
Hyper System Frame Number
HAPS
High Altitude Platform Station
HRNN
Human-Readable Network Name
IAB
Integrated Access and Backhaul
IFRI
Intra Frequency Reselection Indication
I-RNTI
Inactive RNTI
INT-RNTI
Interruption RNTI
KPAS
Korean Public Alarm System
L2
Layer-2
L3
Layer-3
LDPC
Low Density Parity Check
LEO
Low Earth Orbit
MBS
Multicast/Broadcast Services
MCE
Measurement Collection Entity
MCCH
MBS Control Channel
MDBV
Maximum Data Burst Volume
MEO
Medium Earth Orbit
MIB
Master Information Block
MICO
Mobile Initiated Connection Only
MFBR
Maximum Flow Bit Rate
MMTEL
Multimedia telephony
MNO
Mobile Network Operator
MPE
Maximum Permissible Exposure
MRB
MBS Radio Bearer
MT
Mobile Termination
MTCH
MBS Traffic Channel
MTSI
Multimedia Telephony Service for IMS
MU-MIMO
Multi User MIMO
Multi-RTT
Multi-Round Trip Time
MUSIM
Multi-Universal Subscriber Identity Module
NB-IoT
Narrow Band Internet of Things
NCD-SSB
Non Cell Defining SSB
NCGI
NR Cell Global Identifier
NCL
Neighbour Cell List
NCR
Neighbour Cell Relation
NCRT
Neighbour Cell Relation Table
NGAP
NG Application Protocol
NGSO
Non-Geosynchronous Orbit
NID
Network Identifier
NPN
Non-Public Network
NR
NR Radio Access
NSAG
Network Slice AS Group
NTN
Non-Terrestrial Network
P-MPR
Power Management Maximum Power Reduction
P-RNTI
Paging RNTI
PCH
Paging Channel
PCI
Physical Cell Identifier
PDC
Propagation Delay Compensation
PDCCH
Physical Downlink Control Channel
PDSCH
Physical Downlink Shared Channel
PEI
Paging Early Indication
PH
Paging Hyperframe
PLMN
Public Land Mobile Network
PNI-NPN
Public Network Integrated NPN
PO
Paging Occasion
PRACH
Physical Random Access Channel
PRB
Physical Resource Block
PRG
Precoding Resource block Group
PRS
Positioning Reference Signal
PS-RNTI
Power Saving RNTI
PSS
Primary Synchronisation Signal
PTM
Point to Multipoint
PTP
Point to Point
PTW
Paging Time Window
PUCCH
Physical Uplink Control Channel
PUSCH
Physical Uplink Shared Channel
PWS
Public Warning System
QAM
Quadrature Amplitude Modulation
QFI
QoS Flow ID
QMC
QoE Measurement Collection
QoE
Quality of Experience
QPSK
Quadrature Phase Shift Keying
RA
Random Access
RA-RNTI
Random Access RNTI
RACH
Random Access Channel
RANAC
RAN-based Notification Area Code
REG
Resource Element Group
RIM
Remote Interference Management
RLM
Radio Link Monitoring
RMSI
Remaining Minimum SI
RNA
RAN-based Notification Area
RNAU
RAN-based Notification Area Update
RNTI
Radio Network Temporary Identifier
RQA
Reflective QoS Attribute
RQoS
Reflective Quality of Service
RS
Reference Signal
RSRP
Reference Signal Received Power
RSRQ
Reference Signal Received Quality
RSSI
Received Signal Strength Indicator
RSTD
Reference Signal Time Difference
RTT
Round Trip Time
SCS
SubCarrier Spacing
SD
Slice Differentiator
SDAP
Service Data Adaptation Protocol
SDT
Small Data Transmission
SD-RSRP
Sidelink Discovery RSRP
SFI-RNTI
Slot Format Indication RNTI
SHR
Successful Handover Report
SIB
System Information Block
SI-RNTI
System Information RNTI
SLA
Service Level Agreement
SL-RSRP
Sidelink RSRP
SMC
Security Mode Command
SMF
Session Management Function
SMTC
SS/PBCH block Measurement Timing Configuration
S-NSSAI
Single Network Slice Selection Assistance Information
SNPN
Stand-alone Non-Public Network
SNPN ID
Stand-alone Non-Public Network Identity
SPS
Semi-Persistent Scheduling
SR
Scheduling Request
SRAP
Sidelink Relay Adaptation Protocol
SRS
Sounding Reference Signal
SRVCC
Single Radio Voice Call Continuity
SS
Synchronization Signal
SSB
SS/PBCH block
SSS
Secondary Synchronisation Signal
SSSG
Search Space Set Group
SST
Slice/Service Type
SU-MIMO
Single User MIMO
SUL
Supplementary Uplink
TA
Timing Advance
TB
Transport Block
TCE
Trace Collection Entity
TNL
Transport Network Layer
TPC
Transmit Power Control
TRP
Transmit/Receive Point
TRS
Tracking Reference Signal
U2N
UE-to-Network
UCI
Uplink Control Information
UDC
Uplink Data Compression
UE-Slice-MBR
UE Slice Maximum Bit Rate
UL-AoA
Uplink Angles of Arrival
UL-RTOA
Uplink Relative Time of Arrival
UL-SCH
Uplink Shared Channel
UPF
User Plane Function
URLLC
Ultra-Reliable and Low Latency Communications
VR
Virtual Reality
V2X
Vehicle-to-Everything
Xn-C
Xn-Control plane
Xn-U
Xn-User plane
XnAP
Xn Application Protocol
For the purposes of the present document, the terms and definitions given in
TR 21.905, in
TS 36.300 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in
TR 21.905 and
TS 36.300.
BH RLC channel:
an RLC channel between two nodes, which is used to transport backhaul packets.
Boundary IAB-node:
Broadcast MRB:
A radio bearer configured for MBS broadcast delivery.
CAG Cell:
a PLMN cell broadcasting at least one Closed Access Group identity.
CAG Member Cell:
for a UE, a CAG cell broadcasting the identity of the selected PLMN, registered PLMN or equivalent PLMN, and for that PLMN, a CAG identifier belonging to the Allowed CAG list of the UE for that PLMN.
CAG-only cell:
a CAG cell that is only available for normal service for CAG UEs.
Cell-Defining SSB:
an SSB with an RMSI associated.
Child node:
IAB-DU's and IAB-donor-DU's next hop neighbour node; the child node is also an IAB-node.
Conditional Handover (CHO):
a handover procedure that is executed only when execution condition(s) are met.
CORESET#0:
the control resource set for at least SIB1 scheduling, can be configured either via MIB or via dedicated RRC signalling.
DAPS Handover:
a handover procedure that maintains the source gNB connection after reception of RRC message for handover and until releasing the source cell after successful random access to the target gNB.
Direct Path:
a type of UE-to-Network transmission path, where data is transmitted between a UE and the network without sidelink relaying.
Downstream:
direction toward child node or UE in IAB-topology.
Early Data Forwarding:
data forwarding that is initiated before the UE executes the handover.
Earth-centered, earth-fixed:
a global geodetic reference system for the Earth intended for practical applications of mapping, charting, geopositioning and navigation, as specified in
NIMA TR 8350.2 [51].
Feeder link:
wireless link between the NTN Gateway and the NTN payload.
Geosynchronous Orbit:
earth-centered orbit at approximately 35786 kilometres above Earth's surface and synchronised with Earth's rotation. A geostationary orbit is a non-inclined geosynchronous orbit, i.e. in the Earth's equator plane.
Group ID for Network Selection:
an identifier used during SNPN selection to enhance the likelihood of selecting a preferred SNPN that supports a Default Credentials Server or a Credentials Holder, as specified in
TS 23.501.
gNB:
node providing NR user plane and control plane protocol terminations towards the UE, and connected via the NG interface to the 5GC.
High Altitude Platform Station:
airborne vehicle embarking the NTN payload placed at an altitude between 8 and 50 km.
IAB-donor:
gNB that provides network access to UEs via a network of backhaul and access links.
IAB-donor-CU:
IAB-donor-DU:
IAB-DU:
gNB-DU functionality supported by the IAB-node to terminate the NR access interface to UEs and next-hop IAB-nodes, and to terminate the F1 protocol to the gNB-CU functionality, as defined in
TS 38.401, on the IAB-donor.
IAB-MT:
IAB-node function that terminates the Uu interface to the parent node using the procedures and behaviours specified for UEs unless stated otherwise. IAB-MT function used in 38-series of 3GPP Specifications corresponds to IAB-UE function defined in
TS 23.501.
IAB-node:
RAN node that supports NR access links to UEs and NR backhaul links to parent nodes and child nodes. The IAB-node does not support backhauling via LTE.
IAB topology:
the unison of all IAB-nodes and IAB-donor-DUs whose F1 and/or RRC connections are terminated at the same IAB-donor-CU.
Indirect Path:
a type of UE-to-Network transmission path, where data is forwarded via a U2N Relay UE between a U2N Remote UE and the network.
Inter-donor partial migration:
migration of an IAB-MT to a parent node underneath a different IAB-donor-CU while the collocated IAB-DU and its descendant IAB-node(s), if any, are terminated at the initial IAB-donor-CU. The procedure renders the said IAB-node as a boundary IAB-node.
Intra-system Handover:
handover that does not involve a CN change (EPC or 5GC).
Inter-system Handover:
handover that involves a CN change (EPC or 5GC).
Late Data Forwarding:
data forwarding that is initiated after the source NG-RAN node knows that the UE has successfully accessed a target NG-RAN node.
Mapped Cell ID:
in NTN, it corresponds to a fixed geographical area.
MBS Radio Bearer:
A radio bearer configured for MBS delivery.
MSG1:
preamble transmission of the random access procedure for 4-step random access (RA) type.
MSG3:
first scheduled transmission of the random access procedure.
MSGA:
preamble and payload transmissions of the random access procedure for 2-step RA type.
MSGB:
response to MSGA in the 2-step random access procedure. MSGB may consist of response(s) for contention resolution, fallback indication(s), and backoff indication.
Multicast/Broadcast Service:
A point-to-multipoint service as defined in
TS 23.247.
Multicast MRB:
A radio bearer configured for MBS multicast delivery.
Multi-hop backhauling:
using a chain of NR backhaul links between an IAB-node and an IAB-donor.
ng-eNB:
node providing E-UTRA user plane and control plane protocol terminations towards the UE, and connected via the NG interface to the 5GC.
NG-C:
control plane interface between NG-RAN and 5GC.
NG-U:
user plane interface between NG-RAN and 5GC.
NG-RAN node:
either a gNB or an ng-eNB.
Non-CAG Cell:
a PLMN cell which does not broadcast any Closed Access Group identity.
Non-Geosynchronous orbit:
earth-centered orbit with an orbital period that does not match Earth's rotation on its axis. This includes Low and Medium Earth Orbit (LEO and MEO). LEO operates at altitudes between 300 km and 1500 km and MEO at altitudes between 7000 km and 25000 km, approximately.
Non-terrestrial network:
an NG-RAN consisting of gNBs, which provide non-terrestrial NR access to UEs by means of an NTN payload embarked on an airborne or space-borne NTN vehicle and an NTN Gateway.
NR backhaul link:
NR link used for backhauling between an IAB-node and an IAB-donor, and between IAB-nodes in case of a multi-hop backhauling.
NR sidelink communication:
AS functionality enabling at least V2X communication as defined in
TS 23.287 and the ProSe communication (including ProSe non-Relay and UE-to-Network Relay communication) as defined in
TS 23.304, between two or more nearby UEs, using NR technology but not traversing any network node.
NR sidelink discovery:
AS functionality enabling ProSe non-Relay Discovery and ProSe UE-to-Network Relay discovery for Proximity based Services as defined in
TS 23.304 between two or more nearby UEs, using NR technology but not traversing any network node.
NTN Gateway:
an earth station located at the surface of the earth, providing connectivity to the NTN payload using the feeder link. An NTN Gateway is a TNL node.
NTN payload:
a network node, embarked on board a satellite or high altitude platform station, providing connectivity functions, between the service link and the feeder link. In the current version of this specification, the NTN payload is a TNL node.
Numerology:
corresponds to one subcarrier spacing in the frequency domain. By scaling a reference subcarrier spacing by an integer N, different numerologies can be defined.
Parent node:
IAB-MT's next hop neighbour node; the parent node can be IAB-node or IAB-donor-DU.
PC5 Relay RLC channel:
an RLC channel between L2 U2N Remote UE and L2 U2N Relay UE, which is used to transport packets over PC5 for L2 UE-to-Network Relay.
PLMN Cell:
a cell of the PLMN.
RedCap UE:
Relay discovery:
AS functionality enabling 5G ProSe UE-to-Network Relay Discovery as defined in
TS 23.304, using NR technology but not traversing any network node.
Satellite:
a space-borne vehicle orbiting the Earth embarking the NTN payload.
Service link:
wireless link between the NTN payload and UE.
Sidelink Discovery RSRP:
RSRP measurements on PC5 link related to NR sidelink discovery.
Sidelink RSRP:
RSRP measurements on PC5 link related to NR sidelink communication.
SNPN Access Mode:
mode of operation whereby a UE only accesses SNPNs.
SNPN-only cell:
a cell that is only available for normal service for SNPN subscribers.
SNPN Identity:
the identity of Stand-alone NPN defined by the pair (PLMN ID, NID).
Transmit/Receive Point:
part of the gNB transmitting and receiving radio signals to/from UE according to physical layer properties and parameters inherent to that element.
U2N Relay UE:
a UE that provides functionality to support connectivity to the network for U2N Remote UE(s).
U2N Remote UE:
a UE that communicates with the network via a U2N Relay UE.
Upstream:
direction toward parent node in IAB-topology.
Uu Relay RLC channel:
an RLC channel between L2 U2N Relay UE and gNB, which is used to transport packets over Uu for L2 UE-to-Network Relay.
V2X sidelink communication:
AS functionality enabling V2X communication as defined in
TS 23.285, between nearby UEs, using E-UTRA technology but not traversing any network node.
Xn:
network interface between NG-RAN nodes.