3 Definitions and Abbreviations
37.3553GPPLTE Positioning Protocol (LPP)Release 17TS
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1], TS 36.305 [2], TS 23.271 [3], 38.305 [40] and TS 23.273 [42] apply. Other definitions are provided below.
Anchor carrier: In NB-IoT, a carrier where the UE assumes that NPSS/NSSS/NPBCH/SIB-NB for FDD or NPSS/NSSS/NPBCH for TDD are transmitted.
Location Server: a physical or logical entity (e.g., E-SMLC, SUPL SLP, or LMF) that manages positioning for a target device by obtaining measurements and other location information from one or more positioning units and providing assistance data to positioning units to help determine this. A Location Server may also compute or verify the final location estimate.
NB-IoT: NB-IoT allows access to network services via E-UTRA with a channel bandwidth limited to 200 kHz.
Observed Time Difference Of Arrival (OTDOA): The time interval that is observed by a target device between the reception of downlink signals from two different TPs. If a signal from TP 1 is received at the moment t1, and a signal from TP 2 is received at the moment t2, the OTDOA is t2 – t1.
PRS-only TP: A TP which only transmits PRS signals or DL-PRS for PRS-based TBS positioning and is not associated with a cell.
Reference Source: a physical entity or part of a physical entity that provides signals (e.g., RF, acoustic, infra-red) that can be measured (e.g., by a Target Device) in order to obtain the location of a Target Device.
Relative Time Difference (RTD): The relative time difference between a TRP i and a TRP j, is defined as tj – ti, where ti and tj are defined as the time when TRP i and j transmit the start of one subframe respectively.
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.
Target Device: the device that is being positioned (e.g., UE or SUPL SET).
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 PRS-only TP. Transmission Points can include base station (eNodeB) antennas, remote radio heads, a remote antenna of a base station, an antenna of a PRS-only TP, etc. One cell can be formed by 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 Tx Timing Error Group (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, 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.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply.
ADR Accumulated Delta-Range
A‑GNSS Assisted‑GNSS
AoA Angle-of-Arrival
AoD Angle-of-Departure
AP Access Point
ARFCN Absolute Radio Frequency Channel Number
ARP Antenna Reference Point
BDS BeiDou Navigation Satellite System
BIPM Bureau International des Poids et Mesures (International Bureau of Weights and Measures)
BSSID Basic Service Set Identifier
BTS Base Transceiver Station (GERAN)
CID Cell-ID (positioning method)
CNAV Civil Navigation
CRS Cell-specific Reference Signals
DL-AoD Downlink Angle-of-Departure
DL-TDOA Downlink Time Difference Of Arrival
ECEF Earth-Centered, Earth-Fixed
ECGI Evolved Cell Global Identifier
ECI Earth-Centered-Inertial
E‑CID Enhanced Cell-ID (positioning method)
EGNOS European Geostationary Navigation Overlay Service
E-SMLC Enhanced Serving Mobile Location Centre
E-UTRA Evolved Universal Terrestrial Radio Access
E-UTRAN Evolved Universal Terrestrial Radio Access Network
EOP Earth Orientation Parameters
EPDU External Protocol Data Unit
FDMA Frequency Division Multiple Access
FEC Forward Error Correction
FKP (German) Flächen-Korrektur-Parameter (area correction parameter)
FTA Fine Time Assistance
GAGAN GPS Aided Geo Augmented Navigation
GLONASS GLObal’naya NAvigatsionnaya Sputnikovaya Sistema (Engl.: Global Navigation Satellite System)
GNSS Global Navigation Satellite System
GPS Global Positioning System
HA GNSS High-Accuracy GNSS (RTK, PPP)
HPL Horizontal Protection Level
ICD Interface Control Document
IGS International GNSS Service
IOD Issue of Data
IRNSS Indian Regional Navigation Satellite System
IS Interface Specification
LLA Latitude Longitude Altitude
LMF Location Management Function
LOS Line-of-Sight
LPP LTE Positioning Protocol
LPPa LTE Positioning Protocol Annex
LSB Least Significant Bit
MAC Master Auxiliary Concept
MBS Metropolitan Beacon System
MG Measurement Gap
MO-LR Mobile Originated Location Request
MSAS Multi-functional Satellite Augmentation System
MSB Most Significant Bit
msd mean solar day
MT-LR Mobile Terminated Location Request
Multi-RTT Multiple-Round Trip Time
NAV Navigation
NavIC NAVigation with Indian Constellation
NB-IoT NarrowBand Internet of Things
NCGI NR Cell Global Identifier
NICT National Institute of Information and Communications Technology
NI-LR Network Induced Location Request
NLOS Non-Line-of-Sight
NPRS Narrowband Positioning Reference Signals
NR NR Radio Access
NRSRP Narrowband Reference Signal Received Power
NRSRQ Narrowband Reference Signal Received Quality
NTSC National Time Service Center of Chinese Academy of Sciences
OSR Observation Space Representation
OTDOA Observed Time Difference Of Arrival
PBCH Physical Broadcast Channel
PDU Protocol Data Unit
PL Protection Level
PPP Precise Point Positioning
PPW PRS Processing Window
PRB Physical Resource Block
PRC Pseudo‑Range Correction
PRS Positioning Reference Signals
posSIB Positioning System Information Block
PZ-90 Parametry Zemli 1990 Goda – Parameters of the Earth Year 1990
QZS Quasi Zenith Satellite
QZSS Quasi-Zenith Satellite System
QZST Quasi-Zenith System Time
RF Radio Frequency
RP Reception Point
RRC Range‑Rate Correction
Radio Resource Control
RSRP Reference Signal Received Power
RSRPP Reference Signal Received Path Power
RSRQ Reference Signal Received Quality
RSTD Reference Signal Time Difference
RTK Real-Time Kinematic
RTT Round Trip Time
RU Russia
SBAS Space Based Augmentation System
SET SUPL Enabled Terminal
SFN System Frame Number
SLP SUPL Location Platform
SRS Sounding Reference Signal
SS Synchronization Signal
SSB Synchronization Signal Block, SS/PBCH Block
SSID Service Set Identifier
SSR State Space Representation
STEC Slant TEC
SUPL Secure User Plane Location
SV Space Vehicle
TB Terrestrial Beacon
TBS Terrestrial Beacon System
TEC Total Electron Content
TECU TEC Units
TEG Timing Error Group
TIR Target Integrity Risk
TLM Telemetry
TOA Time Of Arrival
TOD Time Of Day
TOW Time Of Week
TP Transmission Point
TRP Transmission-Reception Point
UDRE User Differential Range Error
ULP User Plane Location Protocol
URA User Range Accuracy
USNO US Naval Observatory
UT1 Universal Time No.1
UTC Coordinated Universal Time
VPL Vertical Protection Level
WAAS Wide Area Augmentation System
WGS‑84 World Geodetic System 1984
WLAN Wireless Local Area Network