For the purposes of the present document, the terms and definitions given in
TR 21.905 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.
As used in this document, the suffixes
"-based" and
"-assisted" refer respectively to the node that is responsible for making the positioning calculation (and which may also provide measurements) and a node that provides measurements (but which does not make the positioning calculation). Thus, an operation in which measurements are provided by the UE to the LMF to be used in the computation of a position estimate is described as
"UE-assisted" (and could also be called
"LMF-based"), while one in which the UE computes its own position is described as
"UE-based".
Positioning integrity:
A measure of the trust in the accuracy of the position-related data and the ability to provide associated alerts.
Pre-configured assistance data:
Refers to the DL-PRS assistance data (with associated validity criteria) that can be provided to the UE (before or during an ongoing LPP positioning session), to be then utilized for potential positioning measurements at a future time (e.g. for deferred MT-LR). Pre-configured DL-PRS assistance data may consist of multiple instances, where each instance is applicable to a different area within the network.
Protection Level (PL):
A statistical upper-bound of the Positioning Error (PE) that ensures that, the probability per unit of time of the true error being greater than the AL and the PL being less than or equal to the AL, for longer than the TTA, is less than the required TIR, i.e., the PL satisfies the following inequality:
Prob per unit of time [((PE>AL) & (PL≤AL)) for longer than TTA] < required TIR
When the PL bounds the positioning error in the horizontal plane or on the vertical axis then it is called Horizontal Protection Level (HPL) or Vertical Protection Level (VPL) respectively.
A specific equation for the PL is not specified as this is implementation-defined. For the PL to be considered valid, it must simply satisfy the inequality above.
PRS-only TP:
A TP which only transmits PRS, DL-PRS signals and is not associated with a cell.
PRS Processing Window (PPW):
The PRS Processing Window is configured by the network to a UE for NR DL-PRS measurements without measurement gap.
Reception Point (RP):
A set of geographically co-located receive antennas (e.g. antenna array (with one or more antenna elements)) for one cell, part of one cell or one UL-SRS-only RP. Reception Points can include base station (ng-eNB or gNB) antennas, remote radio heads, a remote antenna of a base station, an antenna of a UL-SRS-only RP, etc. One cell can include one or multiple reception points. For a homogeneous deployment, each reception point may correspond to one cell.
Rx Time Delay:
From a signal reception perspective, there will be a time delay from the time when the RF signal arrives at the Rx antenna to the time when the signal is digitized and time-stamped at the baseband.
Rx Timing Error:
Result of Rx time delay involved in the reception of a signal before reporting measurements that are obtained from the signal. It is the uncalibrated Rx time delay, or the remaining delay after the UE/TRP internal calibration/compensation of the Rx time delay, involved in the reception of the DL-PRS/UL SRS signals. The calibration/compensation may also include the calibration/compensation of the relative time delay between different RF chains in the same UE/TRP and may also possibly consider the offset of the Rx antenna phase centre to the physical antenna centre.
SRS-only RP:
An RP which only receives UL-SRS signals and is not associated with a cell.
Transmission Point (TP):
A set of geographically co-located transmit antennas (e.g. antenna array (with one or more antenna elements)) for one cell, part of one cell or one DL-PRS-only TP. Transmission Points can include base station (ng-eNB or gNB) antennas, remote radio heads, a remote antenna of a base station, an antenna of a DL-PRS-only TP, etc. One cell can include one or multiple transmission points. For a homogeneous deployment, each transmission point may correspond to one cell.
Transmission-Reception Point (TRP):
A set of geographically co-located antennas (e.g. antenna array (with one or more antenna elements)) supporting TP and/or RP functionality.
TRP Rx 'Timing Error Group' (TRP Rx TEG):
Rx timing errors, associated with TRP reporting of one or more UL measurements, that are within a certain margin.
TRP RxTx 'Timing Error Group' (TRP RxTx TEG):
Rx timing errors and Tx timing errors, associated with TRP reporting of one or more gNB Rx-Tx time difference measurements, which have the 'Rx timing errors+Tx timing errors' differences within a certain margin.
TRP Tx 'Timing Error Troup' (TRP Tx TEG):
Tx timing errors, associated with TRP transmissions on one or more DL-PRS resources, that are within a certain margin.
Tx Time Delay:
From a signal transmission perspective, the time delay from the time when the digital signal is generated at baseband to the time when the RF signal is transmitted from the Tx antenna.
Tx Timing Error:
Result of Tx time delay involved in the transmission of a signal. It is the uncalibrated Tx time delay, or the remaining delay after the TRP/UE internal calibration/compensation of the Tx time delay, involved in the transmission of the DL-PRS/UL SRS signals. The calibration/compensation may also include the calibration/compensation of the relative time delay between different RF chains in the same TRP/UE and may also possibly consider the offset of the Tx antenna phase centre to the physical antenna centre.
UE Rx 'Timing Error Group' (UE Rx TEG):
Rx timing errors, associated with UE reporting of one or more DL measurements (RSTD), that are within a certain margin.
UE RxTx 'Timing Error Group' (UE RxTx TEG):
Rx timing errors and Tx timing errors, associated with UE reporting of one or more UE Rx-Tx time difference measurements, which have the 'Rx timing errors+Tx timing errors' differences within a certain margin.
UE Tx 'Timing Error Group' (UE Tx TEG):
Tx timing errors, associated with UE transmissions on one or more UL SRS resources for positioning purpose, that are within a certain margin.
For the purposes of the present document, the abbreviations given in
TR 21.905 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.
5GC
5G Core Network
5GS
5G System
A-AoA
Azimuth-Angle of Arrival
ADR
Accumulated Delta Range
AoA
Angle of Arrival
AP
Access Point
ARP
Antenna Reference Point
BDS
BeiDou Navigation Satellite System
BSSID
Basic Service Set Identifier
CID
Cell-ID (positioning method)
CLAS
Centimetre Level Augmentation Service
DL-AoD
Downlink Angle-of-Departure
DL-PRS
Downlink Positioning Reference Signal
DL-TDOA
Downlink Time Difference Of Arrival
DNU
Do Not Use
E-SMLC
Enhanced Serving Mobile Location Centre
E-CID
Enhanced Cell-ID (positioning method)
ECEF
Earth-Centered, Earth-Fixed
ECI
Earth-Centered-Inertial
EGNOS
European Geostationary Navigation Overlay Service
E-UTRAN
Evolved Universal Terrestrial Radio Access Network
FDMA
Frequency Division Multiple Access
FKP
Flächenkorrekturparameter (Engl: Area Correction Parameters)
GAGAN
GPS Aided Geo Augmented Navigation
GLONASS
GLObal'naya NAvigatsionnaya Sputnikovaya Sistema (Engl.: Global Navigation Satellite System)
GMLC
Gateway Mobile Location Centre
GNSS
Global Navigation Satellite System
GPS
Global Positioning System
GRS80
Geodetic Reference System 1980
HESSID
Homogeneous Extended Service Set Identifier
LCS
LoCation Services
LMF
Location Management Function
LPP
LTE Positioning Protocol
MAC
Master Auxiliary Concept
MBS
Metropolitan Beacon System
MO-LR
Mobile Originated Location Request
MT-LR
Mobile Terminated Location Request
Multi-RTT
Multi-Round Trip Time
NavIC
NAVigation with Indian Constellation
NG-C
NG Control plane
NG-AP
NG Application Protocol
NI-LR
Network Induced Location Request
N-RTK
Network - Real-Time Kinematic
NRPPa
NR Positioning Protocol A
OTDOA
Observed Time Difference Of Arrival
PDU
Protocol Data Unit
posSI
Positioning System Information
posSIB
Positioning SIB
PPP
Precise Point Positioning
PPP-RTK
Precise Point Positioning - Real-Time Kinematic
PRS
Positioning Reference Signal (for E-UTRA)
PRU
Positioning Reference Unit
QZSS
Quasi-Zenith Satellite System
RP
Reception Point
RRM
Radio Resource Management
RSRP
Reference Signal Received Power
RSRPP
Reference Signal Received Path Power
RSRQ
Reference Signal Received Quality
RSSI
Received Signal Strength Indicator
RSTD
Reference Signal Time Difference
RTK
Real-Time Kinematic
SBAS
Space Based Augmentation System
SDT
Small Data Transmission
SET
SUPL Enabled Terminal
SIB
System Information Block
SLP
SUPL Location Platform
SP
Semi-Persistent
SRS
Sounding Reference Signal
SSB
Synchronization Signal Block
SSID
Service Set Identifier
SSR
State Space Representation
STEC
Slant TEC
SUPL
Secure User Plane Location
TADV
Timing Advance
TBS
Terrestrial Beacon System
TEC
Total Electron Content
TEG
Timing Error Group
TP
Transmission Point
TRP
Transmission-Reception Point
TTA
Time To Alert
TxTEG
Tx Timing Error Group
UE
User Equipment
UL-AoA
Uplink Angle of Arrival
UL-RTOA
Uplink Relative Time of Arrival
UL-SRS
Uplink Sounding Reference Signal
UL-TDOA
Uplink Time Difference of Arrival
URA
User Range Accuracy
WAAS
Wide Area Augmentation System
WGS-84
World Geodetic System 1984
WLAN
Wireless Local Area Network
Z-AoA
Zenith Angles of Arrival