ETSI TS 103 246-3 V1.2.1 (2017-03)

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

RTS/SES-00408

General Information

• Status: Published
• Publication Date: 05-Mar-2017
• Technical Committee: SES SCN - Satellite Communications and Navigation
• Current Stage: 12 - Completion
• Due Date: 01-Mar-2017
• Completion Date: 06-Mar-2017
• 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 V1.2.1 (2017-03)

Reference
RTS/SES-00408
Keywords
GNSS, location, navigation, performance,
receiver, satellite, system
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3 ETSI TS 103 246-3 V1.2.1 (2017-03)
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 . 8
3 Definitions and abbreviations . 9
3.1 Definitions . 9
3.2 Abbreviations . 11
4 Overview of GNSS based Location System Performance Features and Classes . 12
4.1 GNSS based Location System (GBLS) . 12
4.2 Performance Features . 13
4.3 Class of Performance requirements . 14
4.4 Use cases associated to Performance Features . 15
5 Performance Requirements . 15
5.1 General . 15
5.2 Horizontal Position Accuracy. 16
5.2.1 Definition . 16
5.2.2 Metrics . 16
5.2.3 Performance requirements . 17
5.2.3.1 Use case: Moving Location Target . 17
5.2.3.1.1 Operational environment: Open area . 17
5.2.3.1.2 Operational environment: Urban area . 18
5.2.3.1.3 Operational environment: Asymmetric area . 18
5.2.3.2 Use case: Static Location Target . 18
5.2.3.2.1 Operational environment: Open area . 18
5.2.3.2.2 Operational environment: Urban area . 19
5.2.3.2.3 Operational environment: Asymmetric area . 19
5.3 Vertical Position Accuracy . 19
5.3.1 Definition . 19
5.3.2 Metrics . 19
5.3.3 Performance requirements . 19
5.3.3.1 Use case: Moving Location Target . 19
5.3.3.1.1 Operational environment: Open area . 19
5.3.3.1.2 Operational environment: Urban area . 20
5.3.3.1.3 Operational environment: Asymmetric area . 20
5.3.3.2 Use case: Static Location Target . 20
5.3.3.2.1 Operational environment: Open area . 20
5.3.3.2.2 Operational environment: Urban area . 20
5.3.3.2.3 Operational environment: Asymmetric area . 21
5.4 GNSS Time Accuracy . 21
5.4.1 Definition . 21
5.4.2 Performance requirements . 21
5.4.2.1 Use case: Moving Location Target . 21
5.4.2.1.1 Operational environment: Open area . 21
5.4.2.1.2 Operational environment: Urban area . 21
5.4.2.1.3 Operational environment: Asymmetric area . 22
5.4.2.2 Use case: Static Location Target . 22
5.4.2.2.1 Operational environment: Open area . 22
5.4.2.2.2 Operational environment: Urban area . 22
5.4.2.2.3 Operational environment: Asymmetric area . 22
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4 ETSI TS 103 246-3 V1.2.1 (2017-03)
5.5 Time-to-First-Fix (TTFF) . 23
5.5.1 Definition . 23
5.5.2 GBLS starting conditions . 23
5.5.3 Performance requirements . 24
5.5.3.1 Use case: Moving Location Target . 24
5.5.3.1.1 Operational environment: Open area . 24
5.5.3.1.2 Operational environment: Urban area . 24
5.5.3.1.3 Operational environment: Asymmetric area . 24
5.5.3.2 Use case: Static Location Target . 25
5.5.3.2.1 Operational environment: Open area . 25
5.5.3.2.2 Operational environment: Urban area . 25
5.5.3.2.3 Operational environment: Asymmetric area . 25
5.6 Position Authenticity . 26
5.6.1 Definition . 26
5.6.2 Metrics . 26
5.6.3 Performance requirements . 26
5.6.3.1 Specific conditions and interference threat scenarios . 26
5.6.3.2 Use case: Moving Location Target . 27
5.6.3.2.1 Operational environment: Open area . 27
5.6.3.2.2 Operational environment: Interference (Spoofing) Scenario . 27
5.6.3.3 Use case: Static Location Target . 27
5.6.3.3.1 Operational environment: Open area . 27
5.6.3.3.2 Operational environment: Interference (Spoofing) scenarios . 28
5.7 Robustness to Interference . 28
5.7.1 Definition . 28
5.7.2 Metrics . 28
5.7.3 Performances requirements . 28
5.7.3.1 Specific conditions and operational environment . 28
5.7.3.2 Use case 1: 20 MHz FM deviation . 29
5.7.3.3 Use case 2: 10 MHz FM deviation . 29
5.8 GNSS Se nsitivity . 30
5.8.1 Definition . 30
5.8.2 Metrics . 30
5.8.3 Performance requirements . 30
5.8.3.1 Operational scenario and specific masking conditions. 30
5.8.3.2 Use case 1: Open area and fine time assistance . 31
5.8.3.3 Use case 2: Asymmetric area and coarse time assistance . 31
5.9 Position Integrity (Protection Level) . 31
5.9.1 Definition . 31
5.9.2 Operational conditions . 32
5.9.3 Use case: Moving Location Target . 32
5.10 Position day-to-day repeatability in the Horizontal Plane . 32
5.10.1 Definition . 32
5.10.2 Metrics . 33
5.10.3 Performance requirements . 34
5.10.3.1 Use case: Moving Location Target . 34
5.10.3.1.1 Operational environment: Open area . 34
5.10.3.1.2 Operational environment: Urban area . 34
5.10.3.1.3 Operational environment: Asymmetric area . 34
5.10.3.2 Use case: Static Location Target . 34
5.10.3.2.1 Operational environment: Open area . 34
5.10.3.2.2 Operational environment: Urban area . 35
5.10.3.2.3 Operational environment: Asymmetric area . 35
5.11 Position day-to-day repeatability in the Vertical Plane . 35
5.11.1 Definition . 35
5.11.2 Metrics . 35
5.11.3 Performance requirements . 36
5.11.3.1 Use case: Moving Location Target . 36
5.11.3.1.1 Operational environment: Open area . 36
5.11.3.1.2 Operational environment: Urban area . 37
5.11.3.1.3 Operational environment: Asymmetric area . 37
5.11.3.2 Use case: Static Location Target . 37
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5 ETSI TS 103 246-3 V1.2.1 (2017-03)
5.11.3.2.1 Operational environment: Open area . 37
5.11.3.2.2 Operational environment: Urban area . 38
5.11.3.2.3 Operational environment: Asymmetric area . 38
5.12 Time-to-Fix-Ambiguity (TTFA) . 38
5.12.1 Definition . 38
5.12.2 Metrics . 38
5.12.3 Performance requirements . 39
5.12.3.1 Use case: Moving Location Target . 39
5.12.3.1.1 Operational environment: Open area . 39
5.12.3.1.2 Operational environment: Urban area . 39
5.12.3.1.3 Operational environment: Asymmetric area . 39
5.12.3.2 Use case: Static Location Target . 40
5.12.3.2.1 Operational environment: Open area . 40
5.12.3.2.2 Operational environment: Urban area . 40
5.12.3.2.3 Operational environment: Asymmetric area . 40
Annex A (normative): Applicable Conditions and Scenarios. 42
A.1 General . 42
A.2 External Location Systems Parameters . 42
A.2.1 GNSS system parameters . 42
A.2.2 Wireless systems parameters . 42
A.3 Operational Environments . 43
A.3.1 Operational Environments definition . 43
A.3.2 Sky Attenuation Conditions . 43
A.3.3 Multipath Level . 45
A.3.4 Magnetic Conditions . 45
A.3.4.1 Output model . 45
A.3.4.2 Perturbation level . 46
A.3.5 Telecommunications Beacons . 46
A.4 Moving Location Target Scenario - Track trajectory . 47
A.5 Moving Location Target Scenario - Straight line trajectory. 48
A.6 Interference source definition . 48
A.7 Authenticity Threat Scenarios . 49
A.7.1 Scenarios description . 49
A.7.2 Moving Location Targets . 49
A.7.3 Static Location Targets . 49
A.7.4 Scenario parameters . 50
A.7.4.1 Attack classification . 50
A.7.4.2 Total spoofing power . 50
A.7.4.3 Misleading information categories . 51
A.8 Integrity Threat Scenarios . 51
A.8.1 Integrity Threat definition . 51
A.8.2 Non-LoS tracking . 51
A.8.3 Pseudo-range Ramp errors . 52
Annex B (informative): Differential GNSS: GBLS implementing differential GNSS and
integrity performance through RTCM standards . 53
B.1 Specific case of a GBLS implementing differential GNSS . 53
B.2 D-GNSS monitoring and integrity concept in RTCM standards . 54
B.2.1 Overall concept and implementation . 54
B.2.2 Monitoring and alerting . 55
B.2.3 D-GNSS integrity performance and system implementation . 55
Annex C (informative): Bibliography . 57
History . 58

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6 ETSI TS 103 246-3 V1.2.1 (2017-03)
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 (https://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. Full details of the entire series can be found in part 1 [7].
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 expansion of location-based applications aims to satisfy more and more complex and diversified user
requirements: this is highlighted for example by the widespread adoption of multi-functional smart-phones or by the
ever wider adoption of tracking devices (e.g. in transport), etc. This requirement for new and innovative location-based
applications is generating a requirement for increasingly complex location systems.
The wide spectrum of location-based applications identified in ETSI TR 103 183 [i.1] calls for a new and broader
concept for location systems, taking into account solutions in which GNSS technologies are complemented with other
technologies to improve robustness and performance. The notion of GNSS-based location systems is introduced and
defined in the present document.
Additional clauses and information related to the implementation in GNSS-based location systems of the various
differential GNSS technologies, namely D-GNSS, RTK and PPP are also included in order to facilitate the use of this
set of standards by manufacturers and service providers.
ETSI
7 ETSI TS 103 246-3 V1.2.1 (2017-03)
1 Scope
This multi-part deliverable addresses integrated GNSS based location systems (GBLS) that combine Global Navigation
Satellite Systems (GNSS), with other navigation technologies, as well as with telecommunication networks in order to
deliver location-based services to users. As a consequence the present document is not applicable to GNSS only
receivers.
This multi-part deliverable proposes a list of functional and performance requirements and related test procedures. For
each performance requirement, different classes are defined allowing the benchmark of different GBLS addressing the
same applications.
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
https://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-200D: "Navstar GPS Space Segment/Navigation User Interfaces", March 7, 2006.
[3] IS-GPS-705D: "Navstar GPS Space Segment/User Segment L5 Interfaces", September 24, 2013.
[4] IS-GPS-800D: "Navstar GPS Space Segment/User Segment L1C Interfaces", September 24, 2013.
[5] "Global Navigation Satellite System GLONASS Interface Control Document", Version 5.1, 2008.
[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".
[9] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[10] RTCM 10401.2: "Standard for Differential Navstar GPS Reference Stations and Integrity Monitors
(RSIM)".
[11] RTCM 10403.2: "Differential GNSS (Global Navigation Satellite Systems) Services".
ETSI
8 ETSI TS 103 246-3 V1.2.1 (2017-03)
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™: "IEEE Standard for Information technology--Telecommunications and
information exchange between systems Local and metropolitan area networks--Specific
requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY)
Specifications".
[i.3] IEEE 802.15™: "Wireless Personal Area Network".
[i.4] IEEE 802.15.1™: "IEEE Standard for Telecommunications and Information Exchange Between
Systems - LAN/MAN - Specific Requirements - Part 15: Wireless Medium Access Control
(MAC) and Physical Layer (PHY) Specifications for Wireless Personal Area Networks
(WPANs)".
[i.5] IEEE 802.15.4a™: "IEEE Standard for Information technology-- Local and metropolitan area
networks-- Specific requirements-- Part 15.4: Wireless Medium Access Control (MAC) and
Physical Layer (PHY) Specifications for Low-Rate Wireless Personal Area Networks (WPANs):
Amendment 1: Add Alternate PHY".
[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.
ETSI
9 ETSI TS 103 246-3 V1.2.1 (2017-03)
[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".
[i.20] Void.
[i.21] IALA Guideline No 1112 on Performance and Monitoring of DGNSS Services in the Frequency
Band 283.5 - 325 kHZ - Edition 1, May 2015.
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
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
authentication: provision of assurance that the location-related data associated with a location target has been derived
from real and not falsified signals
availability: percentage of time when a location system is able to provide the required location-related data
Class A, B, C: categorization of 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.
carrier phase measurement: measure of the range between the satellite and receiver expressed in units of cycles of the
carrier frequency
continuity: likelihood that the location system functionality will be available during the complete duration of the
intended operation if the system is operational at the beginning of the operation
D-GNSS: technique aiming at enhancing position accuracy and integrity of a GNSS receiver by using differential
pseudorange corrections and "do not use flag" for faulty satellites delivered by a GNSS reference station located at a
known location
NOTE: In the present document, the term D-GNSS refer to conventional differential GNSS.
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
GNSS based location system (GBLS): location system using GNSS as the primary source of positioning
GNSS only receiver: location receiver using GNSS as the unique source of positioning
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
integrity: measure of the trust in the accuracy of the location-related data provided by the location system and the
ability to provide timely and valid warnings to users when the location system does not fulfil the condition for intended
operation
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10 ETSI TS 103 246-3 V1.2.1 (2017-03)
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: measure of the time elapsed between the event triggering the determination of the location-related data for a
location target and the availability of the location-related data at the user interface
localisation: process of determining the position or location of a location target
location: 3-dimensional position or location
location-based application: application which is able to deliver a service to one or several users, built on the
processing of the location information (location-related data) related to one or several 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)
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)
NOTE: If a signal from cell 1 is received at the moment t , and a signal from cell 2 is received at the moment t ,
1 2
the OTDOA is t - t
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
Precise Point Positioning (PPP): Differential GNSS technique that uses a worldwide distributed network of reference
stations to provide, in quasi real time, a highly accurate geodetic positioning of a receiver
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
, where I is the
Protection Level (PL): upper bound to the positioning error such that the probability: P(ε > PL) < I
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.
pseudorange: pseudo distance between a satellite and a navigation receiver computed by multiplying the propagation
delay determined by the receiver with the speed of light
Pseudo Range Correction (PRC): simple difference between a pseudorange measured by a GNSS reference station,
set at a known location and the estimated range between the satellite and this known location
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11 ETSI TS 103 246-3 V1.2.1 (2017-03)
Real Time Kinematic (RTK): particular Differential GNSS technique that provides, in real time, highly accurate
positioning of a target based on carrier phase measurements
NOTE 1: In the RTK context, the target is called the "rover", as opposed to the stationary reference station(s). RTK
makes use of the carrier phase measurements, both in the reference station and in the rover, and this
technique allows the ambiguities affecting these accurate measurements to be resolved.
NOTE 2: If the reference station is at an accurately known location, the rover can compute its accurate geodetic (or
absolute) location. Alternatively, if the reference station's geodetic location is only roughly known, RTK
can still provide high accuracy, but only on a relative and not absolute basis.
reference receiver: receiver placed at a known and surveyed position used for differential GNSS technique
NOTE:
...