ETSI TS 103 246-3 V1.1.1 (2015-07)

Satellite Earth Stations and Systems (SES); GNSS based location systems; Part 3: Performance requirements

DTS/SES-00332

General Information

• Status: Published
• Publication Date: 30-Jul-2015
• Technical Committee: SES SCN - Satellite Communications and Navigation
• Current Stage: 12 - Completion
• Due Date: 28-Jul-2015
• Completion Date: 31-Jul-2015
• Mandate: M/496

Standards Content (Sample)

TECHNICAL SPECIFICATION
Satellite Earth Stations and Systems (SES);
GNSS based location systems;
Part 3: Performance requirements

2 ETSI TS 103 246-3 V1.1.1 (2015-07)

Reference
DTS/SES-00332
Keywords
GNSS, location, navigation, performance,
receiver, satellite, system
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ETSI
3 ETSI TS 103 246-3 V1.1.1 (2015-07)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 7
3 Definitions and abbreviations . 9
3.1 Definitions . 9
3.2 Abbreviations . 10
4 Overview of GNSS-based Location System Performance Features and Classes . 11
4.1 GNSS-based Location System (GBLS) . 11
4.2 Performance Features . 12
4.3 Class of Performance requirements . 13
4.4 Use cases associated to Performance Features . 13
5 Performance Requirements . 14
5.1 General . 14
5.2 Horizontal Position Accuracy. 14
5.2.1 Definition . 14
5.2.2 Metrics . 14
5.2.3 Performance requirements . 16
5.2.3.1 Use case: Moving Location Target . 16
5.2.3.1.1 Operational environment: Open area . 16
5.2.3.1.2 Operational environment: Urban area . 16
5.2.3.1.3 Operational environment: Asymmetric area . 17
5.2.3.2 Use case: Static Location Target . 17
5.2.3.2.1 Operational environment: Open area . 17
5.2.3.2.2 Operational environment: Urban area . 18
5.2.3.2.3 Operational environment: Asymmetric area . 18
5.3 Vertical Position Accuracy . 18
5.3.1 Definition . 18
5.3.2 Metrics . 18
5.3.3 Performance requirements . 18
5.3.3.1 Use case: Moving Location Target . 18
5.3.3.1.1 Operational environment: Open area . 18
5.3.3.1.2 Operational environment: Urban area . 19
5.3.3.1.3 Operational environment: Asymmetric area . 19
5.3.3.2 Use case: Static Location Target . 19
5.3.3.2.1 Operational environment: Open area . 19
5.3.3.2.2 Operational environment: Urban area . 20
5.3.3.2.3 Operational environment: Asymmetric area . 20
5.4 GNSS Time Accuracy . 20
5.4.1 Definition . 20
5.4.2 Performance requirements . 20
5.4.2.1 Use case: Moving Location Target . 20
5.4.2.1.1 Operational environment: Open area . 20
5.4.2.1.2 Operational environment: Urban area . 20
5.4.2.1.3 Operational environment: Asymmetric area . 21
5.4.2.2 Use case: Static Location Target . 21
5.4.2.2.1 Operational environment: Open area . 21
5.4.2.2.2 Operational environment: Urban area . 21
5.4.2.2.3 Operational environment: Asymmetric area . 21
5.5 Time-to-First-Fix (TTFF) . 22
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4 ETSI TS 103 246-3 V1.1.1 (2015-07)
5.5.1 Definition . 22
5.5.2 GBLS starting conditions . 22
5.5.3 Performance requirements . 23
5.5.3.1 Use case: Moving Location Target . 23
5.5.3.1.1 Operational environment: Open area . 23
5.5.3.1.2 Operational environment: Urban area . 23
5.5.3.1.3 Operational environment: Asymmetric area . 23
5.5.3.2 Use case: Static Location Target . 24
5.5.3.2.1 Operational environment: Open area . 24
5.5.3.2.2 Operational environment: Urban area . 24
5.5.3.2.3 Operational environment: Asymmetric area . 25
5.6 Position Authenticity . 25
5.6.1 Definition . 25
5.6.2 Metrics . 25
5.6.3 Performance requirements . 25
5.6.3.1 Specific conditions and interference threat scenarios . 25
5.6.3.2 Use case: Moving Location Target . 26
5.6.3.2.1 Operational environment: Open area . 26
5.6.3.2.2 Operational environment: Interference (Spoofing) Scenario . 26
5.6.3.3 Use case: Static Location Target . 26
5.6.3.3.1 Operational environment: Open area . 26
5.6.3.3.2 Operational environment: Interference (Spoofing) scenarios . 26
5.7 Robustness to Interference . 27
5.7.1 Definition . 27
5.7.2 Metrics . 27
5.7.3 Performances requirements . 27
5.7.3.1 Specific conditions and operational environment . 27
5.7.3.2 Use case 1: 20 MHz FM deviation . 27
5.7.3.3 Use case 2: 10 MHz FM deviation . 28
5.8 GNSS Se nsitivity . 29
5.8.1 Definition . 29
5.8.2 Metrics . 29
5.8.3 Performance requirements . 29
5.8.3.1 Operational scenario and specific masking conditions. 29
5.8.3.2 Use case 1: Open area and fine time assistance . 30
5.8.3.3 Use case 2: Asymmetric area and coarse time assistance . 30
5.9 Position Integrity (Protection Level) . 30
5.9.1 Definition . 30
5.9.2 Operational conditions . 31
5.9.3 Use case: Moving Location Target . 31
Annex A (Normative): Applicable Conditions and Scenarios. 32
A.1 General . 32
A.2 External Location Systems Parameters . 32
A.2.1 GNSS system parameters . 32
A.2.2 Wireless systems parameters . 32
A.3 Operational Environments . 33
A.3.1 Operational Environments definition . 33
A.3.2 Sky Attenuation Conditions . 33
A.3.3 Multipath Level . 35
A.3.4 Magnetic Conditions . 35
A.3.4.1 Output model . 35
A.3.4.2 Perturbation level . 36
A.3.5 Telecommunications Beacons . 36
A.4 Moving Location Target Scenario - Track trajectory . 37
A.5 Moving Location Target Scenario - Straight line trajectory. 38
A.6 Interference source definition . 38
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5 ETSI TS 103 246-3 V1.1.1 (2015-07)
A.7 Authenticity Threat Scenarios . 39
A.7.1 Scenarios description . 39
A.7.2 Moving Location Targets . 39
A.7.3 Static Location Targets . 39
A.7.4 Scenario parameters . 40
A.7.4.1 Attack classification . 40
A.7.4.2 Total spoofing power . 40
A.7.4.3 Misleading information categories . 41
A.8 Integrity Threat Scenarios . 41
A.8.1 Integrity Threat definition . 41
A.8.2 Non-LoS tracking . 41
A.8.3 Pseudo-range Ramp errors . 41
Annex B (informative): Bibliography . 43
History . 44

ETSI
6 ETSI TS 103 246-3 V1.1.1 (2015-07)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://ipr.etsi.org).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPR's not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and
Systems (SES).
The present document is part 3 of a multi-part deliverable covering GNSS-based Location Systems (GBLS), as
identified below:
Part 1: Functional requirements;
Part 2: Reference Architecture;
Part 3: Performance requirements;
Part 4: Requirements for location data exchange protocols;
Part 5: Performance test specification.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
The increasing proliferation of location-based services is based on several trends in user applications and devices; these
include notably the widespread adoption of multi-functional smart-phones etc., and the wider adoption of tracking
devices (e.g. in transport). This need for new and innovative location-based services is generating a need for
increasingly complex location systems. These systems are designed to deliver location-related information for one or
more location targets to user applications.
The wide spectrum of technical features identified in ETSI TR 103 183 [i.1] calls for a new and broader concept for
location systems, taking into account hybrid solutions in which GNSS technologies are complemented with other
technology sensors to improve robustness and the performance.
ETSI
7 ETSI TS 103 246-3 V1.1.1 (2015-07)
1 Scope
The present document addresses performance requirements for GNSS-based Location Systems (GBLSs) that combine
Global Navigation Satellite Systems (GNSS - e.g. Galileo™) and other navigation technologies with telecommunication
networks for delivery of location-based services.
The present document defines Performance Features applicable to GBLS and specifies the conditions and requirements
for these Performance Features.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long-term validity.
The following referenced documents are necessary for the application of the present document.
[1] European GNSS (Galileo™) Open Service (Issue 1.1): "Signal In Space Interface Control
Document".
[2] IS-GPS-200 (March 7, 2006): "Revision D, Navstar GPS Space Segment/Navigation User
Interfaces".
[3] IS-GPS-705 (September 22, 2005): "Navstar GPS Space Segment/User Segment L5 Interfaces".
[4] IS-GPS-800 (September 4, 2008): "Navstar GPS Space Segment/User Segment L1C Interfaces".
[5] "Global Navigation Satellite System GLONASS Interface Control Document", Version 5, 2002.
[6] BDS-SIS-ICD-B1I-2.0 (December 2013): "BeiDou Navigation Satellite System Signal In Space
Interface Control Document Open Service Signal (Version 2.0)".
[7] ETSI TS 103 246-1: "Satellite Earth Stations and Systems (SES); GNSS based location systems;
Part 1: Functional requirements".
[8] ETSI TS 103 246-2: "Satellite Earth Stations and Systems (SES); GNSS based location systems;
Part 2: Reference Architecture".
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long-term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI TR 103 183: "Satellite Earth Stations and Systems (SES); Global Navigation Satellite
Systems (GNSS) based applications and standardisation needs".
[i.2] IEEE 802.11™: "Wireless Local Area Networks".
ETSI
8 ETSI TS 103 246-3 V1.1.1 (2015-07)
[i.3] IEEE 802.15™: "Wireless Personal Area Network".
[i.4] IEEE 802.15.1™ (for Bluetooth).
[i.5] IEEE 802.15.4a™ (for low rate WPAN).
[i.6] ETSI TS 145 001: "Digital cellular telecommunications system (Phase 2+); Physical layer on the
radio path; General description (3GPP TS 45.001)".
[i.7] ETSI TS 125 104: "Universal Mobile Telecommunications System (UMTS); Base Station (BS)
radio transmission and reception (FDD) (3GPP TS 25.104)".
[i.8] ETSI TS 136 171: "LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Requirements
for Support of Assisted Global Navigation Satellite System (A-GNSS) (3GPP TS 36.171)".
[i.9] R. Grover Brown and Gerald Y. Chin: "GPS RAIM: Calculation of Threshold and Protection
Radius Using Chi-Square Methods - A Geometric Approach", Global Positioning System: Inst.
Navigat., Volume V, pages 155-179, 1997.
[i.10] Juan Blanch et al.: "An Optimized Multiple Hypothesis RAIM Algorithm for Vertical Guidance",
Proceedings of ION GNSS 2007, Fort Worth (TX) September 2007.
[i.11] Miguel Azaola et al.: "Isotropy-Based Protection Levels: a Novel Method for Autonomous
Protection Level Computation with Minimum Assumptions", NAVITEC 2008, Noordwijk (The
Netherlands), December 2008.
nd
[i.12] Clark, B., Bevly, D.: "FDE Implementations for a Low-Cost GPS/INS Module", 22 International
Meeting of the Satellite Division of The Institute of Navigation, Savannah, GA, September 22-25,
2009.
[i.13] Walter, T., Enge, P., Blanch, J. and Pervan, B.: "Worldwide Vertical Guidance of Aircraft Based
on Modernised GPS and New Integrity Augmentations", Proceedings of the IEEE Volume 96,
Number 12, December 2008.
[i.14] Gratton, L., Joerger, M., Pervan, B: "Carrier Phase Relative RAIM Algorithms and Protection
Level Derivation", Journal of Navigation Volume 63, Number 2, April 2010.
st
[i.15] Lee, Y: "Optimization of Position Domain Relative RAIM", ION GNSS 21 International
Technical Meeting of the Satellite Division, Savannah, GA, September 16-19, 2008.
[i.16] M. Spangenberg PhD Thesis: "Safe navigation for vehicles", Ecole doctorale Mathématiques,
Informatique et Télécommunications de Toulouse, Laboratoire de Télécommunications Spatiales
et Aéronautiques (TéSA), June 2009.
[i.17] J.L. Farrell: "Full integrity testing for GPS/INS", Journal of the institute of navigation Volume 53,
Number 1, Spring 2006, USA.
nd
[i.18] Clark, B., Bevly, D.: "FDE Implementations for a Low-Cost GPS/INS Module", 22 International
Meeting of the Satellite Division of The Institute of Navigation, Savannah, GA, September 22-25,
2009.
[i.19] DO-316: "Minimum Operational Performance Standards for Global Positioning System/Aircraft
Base Augmentation System".
ETSI
9 ETSI TS 103 246-3 V1.1.1 (2015-07)
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document the following terms and definitions apply:
almanac: information transmitted by a GNSS satellite consisting of coarse orbit and status information for each satellite
in the constellation, an Ionospheric model, and information to relate GPS derived time to Coordinated Universal Time
(UTC)
architecture: abstract representation of a communications system, in this case representing functional elements of the
system and associated logical interfaces
assistance: use of position data available from a telecommunications network to enable a GNSS receiver to acquire and
calculate position (A-GNSS) under adverse satellite reception conditions
availability: measures percentage of time when a location system is able to provide the required location-related data
class A, B, C: classes categorize the performance level of the GBLS for a given performance feature
NOTE: In all cases Class A is the highest performance class and C is the lowest.
continuity: likelihood that the navigation signal-in-space supports accuracy and integrity requirements for duration of
intended operation
NOTE: Continuity aids a user to start an operation during a given exposure period without an interruption of this
operation and assuming that the service was available at beginning of the operation. Related to the
Continuity concept, a Loss of Continuity occurs when the user is forced to abort an operation during a
specified time interval after it has begun (the system predicts service was available at start of operation).
continuity risk: probability of detected but unscheduled navigation interruption after initiation of an operation
electromagnetic interference: any source of RF transmission that is within the frequency band used by a
communication link, and that degrades the performance of this link
NOTE: Jamming is a particular case of electromagnetic interference.
Horizontal Dilution Of Precision (HDOP): measure of position determination accuracy that is a function of the
geometrical layout of the satellites used for the fix, relative to the receiver antenna
measure of the trust in the accuracy of the location-related data provided by the location system
integrity:
NOTE: Integrity is expressed through the computation of a protection level. The Integrity function includes the
ability of the location system to provide timely and valid warnings to users when the system does not
fulfil the condition for intended operation. Specifically, a location system is required to deliver a warning
(an alert) of any malfunction (as a result of a set alert limit being exceeded) to users within a given period
of time (time-to-alert). Related to the Integrity concept, a Loss of Integrity event occurs when an unsafe
condition occurs without annunciation for a time longer than the time-to-alert limit.
integrity risk: risk that a positioning error is greater than a protection level per independent sample of time
jamming: deliberate transmission of interference to disrupt processing of wanted signals (which in this case are GNSS
or telecommunications signals)
NOTE: Spoofing is considered to be a deceptive form of jamming.
latency: time elapsed between the event triggering the determination of the location-related data for (a) location
target(s) (i.e. location request from external client, external or internal event triggering location reporting), and the
availability of the location-related data at the user interface
localization: process of determining the position or location of a location target
location: 3-dimensional position or location
location-based application: application that is able to deliver a location-based service to one or several users
ETSI
10 ETSI TS 103 246-3 V1.1.1 (2015-07)
location-based service: service built on the processing of the Location-related data associated with one or several
location targets
location-related data: set of data associated with a given location target, containing at least one or several of the
following time-tagged information elements: location target position, location target motion indicators (velocity and
acceleration), and Quality of Service indicators (estimates of the position accuracy, reliability or authenticity)
NOTE: This data is the main output of a Location system.
location system: system responsible for providing to a location based application the Location-related data of one or
several location targets
location target: physical entity on whose position the location system builds the location-related data
NOTE: This entity may be mobile or stationary.
Observed Time Difference Of Arrival (OTDOA): time interval observed between the reception of downlink signals
from two different cells (in a cellular telecoms system). If a signal from cell 1 is received at the moment t , and a signal
from cell 2 is received at the moment t , the OTDOA is t - t
2 2 1
performance feature: set of performance requirements for a given location-related data category produced by the
GBLS
position: 3-dimensional position or location
positioning: process of determining the position or location of a location target
privacy: function of a location system that aims at ensuring that the location target user private information (identity,
bank accounts, etc.) and its location-related data cannot be accessed by a non-authorized third party
Protection Level (PL): upper bound to the positioning error such that the probability: P(ε > PL) < I , where I is the
risk risk
integrity risk and ε is the position error
NOTE: The protection level is provided by the location system, and with the integrity risk, is one of the two
sub-features of the integrity system.
Pseudo-Random Noise Code (PRN): unique binary code (or sequence) transmitted by a GNSS satellite to allow a
receiver to determine the travel time of the radio signal from satellite to receiver
Quality of Service (QoS): set of indicators that can accompany the location target's position/motion information and is
intended to reflect the quality of the information provided by the location system
NOTE: QoS indicators can be an accuracy estimate, a protection level statistic, integrity risk, and authenticity
flag.
security: function of a location system that aims at ensuring that the location-related data is safeguarded against
unapproved disclosure or usage inside or outside the location system, and that it is also provided in a secure and reliable
manner that ensures it is neither lost nor corrupted
spoofing: transmission of signals intended to deceive location processing into reporting false location target data e.g.
meaconing
time-to-alert: time from when an unsafe integrity condition occurs to when an alerting message reaches the user
vertical axis: axis locally defined for the location target, collinear to the zenith/nadir axis
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
rd
3GPP 3 Generation Partnership Project
A-GNSS Assisted GNSS
AL Alarm Limit
EGNOS European Geostationary Navigation Overlay System
EMI Electro-Magnetic Interference
E-UTRA Evolved - UMTS Terrestrial Radio Access
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11 ETSI TS 103 246-3 V1.1.1 (2015-07)
FFS For Further Study
FM Frequency Modulation
GBLS GNSS-based Location System
GEO Geostationary Earth Orbit
GIC GNSS Integrity Channel
GLONASS Global Navigation Satellite System (Russian based system)
GNSS Global Navigation Satellite System
GPS Global Positioning System
GSM Global System for Mobile communications
HDOP Horizontal Dilution of Precision
HPE Horizontal Positioning Error
HPL Horizontal Protection Level
INS Inertial Navigation Sensor
ITS Intelligent Transport Systems
LoS Line of Sight
LTE Long-Term Evolution
n/a Not Applicable
OS Open Service
OTDOA Observed Time Difference of Arrival
PL Protection Level
PRN Pseudo-Random Noise code
PVT Position, Velocity and Time
QoS Quality of Service
RAIM Receiver Autonomous Integrity Monitoring
RF Radio Frequency
SF Scale Factor
TBD To Be Defined
TSP Total Spoofing Power
TTFF Time-To-Tirst-Fix
UMTS Universal Mobile Telecommunications System
UMTS Universal Mobile Telecommunications System
UTRA UMTS Terrestrial Radio Access
Wi-Fi Wireless Fidelity
WPAN Wireless Personal Area Network
4 Overview of GNSS-based Location System
Performance Features and Classes
4.1 GNSS-based Location System (GBLS)
The present document defines the performance requirements applicable to GNSS-based Location System (GBLS)
location-related data.
GBLS Functional Requirements and Reference Architecture in ETSI TS 103 246-1 [7] and ETSI TS 103 246-2 [8] shall
apply. A GBLS intends to provide one or more users with location-related data associated with one or more location
targets. Figure 1 is an extract of ETSI TS 103 246-2 [8] and depicts the GBLS Architecture (level 2).

ETSI
12 ETSI TS 103 246-3 V1.1.1 (2015-07)
Positioning Module
Central Facility
Central Management
Centralised
On-board
On-board Module
Localisation
Localisation
Localisation
Sensor
Module
Sensor Core
Module
Core
Module Assistance
Management
Management Interface
Interface
Towards Server To
external External
(GNSS and
(GNSS and
positioning Service
other Sensors)
other Sensors)
system provider
Application
Application
Application
Interface Module
Interface Module
Interface Module
To application To application
Key:
Mandatory
Optional
Figure 1: GNSS-based Location System (GBLS) Architecture
4.2 Performance Features
Location-related data delivered by a GNSS-based Location System is required to meet a number of performance
requirements, derived from GBLS Functional requirements ETSI TS 103 246-1 [7]. These performance requirements
are grouped in categories called Performance Features.
A detailed definition of each Performance Feature with its attributes and metrics is given in clause 5. Table 1 lists the
Performance Features included in this technical specification and other additional features identified but left for further
study (FFS):
Table 1: GBLS Performance Features
Performance Feature Corresponding clause
Horizontal Position Accuracy 5.2
Vertical Position Accuracy 5.3
GNSS Time Accuracy 5.4
Time-To-First-Fix 5.5
Position Authenticity 5.6
Robustness to Interference 5.7
GNSS Sensitivity 5.8
Position Integrity (Protection Level) 5.9
Availability of Required Accuracy
FFS
(probability that PVT data is provided with a certain level of accuracy)
EMI Localization Accuracy
FFS
(error of location measurement of an interfering signal)
GNSS-Denied Accuracy
FFS
(error in PVT data when there is a loss of GNSS signal reception)
Position Integrity (Time-to-Alert)
(the time from occurrence of an unsafe integrity condition to the issue of FFS
an alerting message)
Position Integrity (Time-to-Recover-from-Alert)
(the time from cancellation of an unsafe integrity condition to removal of FFS
an alerting message)
Accuracy of speed and acceleration
FFS
(horizontal and vertical)
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13 ETSI TS 103 246-3 V1.1.1 (2015-07)
4.3 Class of Performance requirements
Associated with each Performance feature, a set of Performance requirements is defined for one or several use cases.
Three Classes of performance (A, B and C) are defined in order to categorize the performance level of the GBLS for a
given Performance feature. In all cases Class A is the highest performance class and C is the lowest. The classes'
contents in term of performance requirements are driven by the different implementations of the reference architecture
ETSI TS 103 246-1 [7].
Performance features shall be considered independently of each other and for a given GBLS not all Performance
features shall be necessarily addressed. The choice of applicable Performance features is left to users in accordance with
the requirements of their targeted applications. The GBLS class of performance shall be established for each chosen
performance feature and may not be the same for all of them.
For each Performance feature one or several use cases with different operational environments for each use case are
considered, with corresponding metric measurements for Performance classes A, B and C. A Performance feature
associated to a given use case and a given operational environment shall be considered independent to another
combination. The choice of one or several use cases as well as the choice of operating environments with their
corresponding Performance class is left to users in accordance with the requirement of their targeted applications.
However, the compliance to a given Performance class (A, B or C) requires all metrics of the table to be met. The
compliance to a Performance class does not require conformance to all use cases and all associated operational
environments for that particular Performance feature.
Table 2 provides an example of selection of Performance Class for a specific GBLS application for Performance
features, with different combinations of use cases with operational conditions and Performance classes.
Table 2: Example of selection of Performance Class for a specific GBLS application
Operational
Performance Features Use cases Selected
Environments
(defined in clause 5) (defined in annex A) Performance Class
(defined in annex A)
Open Area Class A
Static Location Target
Urban Area Class B
Horizontal Accuracy
Urban Area Class B
Moving Location Target
Asymmetric Area Class C
Vertical Accuracy Static Location Target Open Area Class B
GNSS Time Accuracy Performance Feature not considered for this specific application
Open Area
Time-to-first-fix Static Location Target
Class C
Urban Area
Static Location target
Interference (spoofing) Class A
scenario
Position Authenticity Open Area
Moving Location Target
Interference (spoofing) Class B
scenario
Moving Location Target
Class B
20 MHz deviation with J#2
Robustness to Interference Open Area
Moving Location Target
Class C
10 MHz deviation with J#1
GNSS Sensitivity Performance Feature not considered for this specific application
Position Integrity & Protection
Moving Location Target Urban Area Class C
Level
4.4 Use cases
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