ETSI TS 137 571-4 V18.4.0 (2026-04)

Universal Mobile Telecommunications System (UMTS); LTE; 5G; User Equipment (UE) conformance specification for UE positioning; Part 4: Test suites (3GPP TS 37.571-4 version 18.4.0 Release 18)

RTS/TSGR-0537571-4vi40

General Information

• Status: Not Published
• Technical Committee: 3GPP RAN 5 - Mobile Terminal Conformance Testing (formely T1)
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 02-Apr-2026

Standards Content (Sample)

TECHNICAL SPECIFICATION
Universal Mobile Telecommunications System (UMTS);
LTE;
5G;
User Equipment (UE)
conformance specification for UE positioning;
Part 4: Test suites
(3GPP TS 37.571-4 version 18.4.0 Release 18)


3GPP TS 37.571-4 version 18.4.0 Release 18 1 ETSI TS 137 571-4 V18.4.0 (2026-04)

Reference
RTS/TSGR-0537571-4vi40
Keywords
5G,LTE,UMTS
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ETSI
3GPP TS 37.571-4 version 18.4.0 Release 18 2 ETSI TS 137 571-4 V18.4.0 (2026-04)
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ETSI
3GPP TS 37.571-4 version 18.4.0 Release 18 3 ETSI TS 137 571-4 V18.4.0 (2026-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
Introduction . 6
1 Scope . 7
2 References . 7
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 9
3.3 Abbreviations . 9
4 A-GPS system architecture and test model . 9
4.1 ATS and module structure . 9
4.2 Upper tester . 9
4.3 SV PCO . 9
4.4 A-GPS Primitives . 9
4.5 Specific test suite operation for A-GPS testing . 9
5 A-GNSS and LTE positioning system architecture and test models . 10
5.1 Test system architecture . 10
5.1.1 General system architecture . 10
5.1.2 Component architecture . 10
5.1.2.1 Interfaces . 11
5.2 Test model . 11
5.2.1 LTE GNSS test model . 12
5.2.2 UTRA A-GNSS test model . 13
5.3 ASP specifications . 14
5.4 LTE OTDOA test model . 14
5.5 LTE ECID test model . 15
6 LTE indoor positioning system architecture and test models . 15
6.1 Test system architecture . 15
6.1.1 General system architecture . 15
6.1.2 Component architecture . 15
6.1.2.1 Interfaces . 16
6.2 Test model . 16
6.2.1 LTE indoor positioning test model . 16
6A LTE test models requiring GNSS support . 17
6B NG-RAN NR positioning system architecture and test models . 17
6B.1 Test system architecture . 17
6B.1.1 General system architecture . 17
6B.1.2 Component architecture . 17
6B.2 Test models . 18
6B.2.1 NR GNSS positioning test model . 18
6B.2.2 NR indoor positioning test model . 19
6B.2.3 NR OTDOA (LTE) positioning test model . 19
6B.2.4 NR Multi-RTT, DL-AoD and DL-TDOA positioning test model . 21
6B.2.5 NR E-CID test model . 21
6B.2.6 NR SLPP over NR sidelink test model . 22
6C NR/5GC test models requiring GNSS support . 23
6D Test methods and design considerations . 24
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6D.1 SLPP . 24
7 Upper Tester Interface . 25
7.1 MMI for A-GPS . 25
7.2 MMI for A-GNSS, LTE and NR positioning . 25
8 IXIT Proforma . 25
8.1 A-GPS test suite parameters declarations . 25
8.2 A-GNSS, LTE and NR positioning test suite parameters declarations . 26
9 Other SS Requirements with TTCN-3 impact. 26
9.1 Codec Requirements. 26
Annex A (normative): Test Suites . 27
A.1 UTRA A-GPS test suite . 27
A.1.1 Baseline of specifications . 27
A.1.2 AGPS ATS . 27
A.1.3 The TTCN Machine Processable form (TTCN.MP) . 28
A.2 UTRA A-GNSS, LTE and NR/5GC positioning test suite . 28
A.2.1 Baseline of specifications . 28
A.2.2 E-UTRA LTE positioning Test Cases . 28
A.2.3 UTRA A-GNSS Test Cases. 29
A.2.4 NR/5GC Test Cases. 29
Annex B (informative): ASN.1 modules . 31
B.1 A-GPS ASN.1 module . 31
B.2 A-GNSS ASN.1 modules . 31
B.3 LPP ASN.1 . 31
B.4 SLPP ASN.1 . 31
Annex C (informative) E-UTRA System Simulator Extension ASP Definitions in TTCN-3 . 32
C.1 EUTRA_POS_ASP_TypeDefs . 32
C.1.1 System_Configuration_PosExt . 32
C.1.2 Cell_Configuration_PosExt . 32
C.1.2.1 Cell_Configuration_Common_PosExt . 32
C.1.2.2 Downlink_Physical_Layer_Configuration_PosExt . 33
C.1.3 System_Interface_PosExt . 33
C.2 References to TTCN-3 . 34
Annex D (informative) Positioning System Simulator ASP Definitions in TTCN-3 . 35
D.1 PosSystem_ASP_TypeDefs . 35
D.1.1 PosSystem_Load_Scenario . 35
D.1.2 PosSystem_Retrieve_Data . 36
D.1.2.1 SatSystem_Retrieve_UTRAN_Data . 36
D.1.2.2 PosSystem_Retrieve_LPP_Data . 37
D.1.2.3 PosSystem_Retrieve_Data_Common . 38
D.1.3 PosSystem_PowerControl . 38
D.1.4 PosSystem_GnssUtcTime . 39
D.1.5 System_Interface . 39
D.2 CommonDefs . 40
D.3 References to TTCN-3 . 41
Annex E (informative) NR5GC System Simulator Extension ASP Definitions in TTCN-3 . 42
E.1 NR5GC_POS_ASP_TypeDefs . 42
E.1.1 NR_System_Configuration_PosExt . 42
E.1.2 NR_Cell_Configuration_PosExt . 42
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E.1.2.1 NR_Cell_Configuration_Common_PosExt . 42
E.1.2.2 Downlink_Physical_Layer_Configuration_PosExt . 43
E.1.3 NR_System_Interface_PosExt . 44
E.2 References to TTCN-3 . 45
Annex F (informative) NR Sidelink System Simulator Extension ASP Definitions in TTCN-3 . 46
F.1 NR5GC_SL_POS_ASP_TypeDefs . 46
F.1.1 NR_SL_System_Configuration_PosExt . 46
F.1.2 NR_SL_SS_UE_Config_PosExt . 46
F.1.2.1 NR_SL_PRS_Pool_Configuration . 48
F.1.3 NR_Sidelink_System_Interface_PosExt . 52
F.2 References to TTCN-3 . 52
Annex G (informative): Change history . 53
History . 61

ETSI
3GPP TS 37.571-4 version 18.4.0 Release 18 6 ETSI TS 137 571-4 V18.4.0 (2026-04)
Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
Introduction
The present document is part 4 of a multi-part conformance test specification. The specification contains a TTCN
design frame work and the detailed test specifications in TTCN for the UE:
- A-GPS at the UTRA Uu interface in TTCN-2;
- A-GNSS at the UTRA Uu interface in TTCN-3;
- LTE positioning at the LTE-Uu interface in TTCN-3.
- NR positioning at the NR-Uu interface in TTCN-3.
The present document is part 4 of a multi-parts TS:
- 3GPP TS 37.571-1: User Equipment (UE) conformance specification for UE positioning; Part 1: Terminal
conformance.
- 3GPP TS 37.571-2: User Equipment (UE) conformance specification for UE positioning; Part 2: Protocol
conformance.
- 3GPP TS 37.571-3: User Equipment (UE) conformance specification for UE positioning; Part 3: Implementation
Conformance Statement (ICS).
- 3GPP TS 37.571-4: User Equipment (UE) conformance specification for UE positioning; Part 4: Test
suites.
- 3GPP TS 37.571-5: User Equipment (UE) conformance specification for UE positioning; Part 5: Test scenarios
and assistance data.
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1 Scope
The present document specifies the protocol and signalling conformance testing in TTCN for the UE:
- A-GPS at the UTRA Uu interface;
- LTE positioning at the LTE-Uu interface;
- A-GNSS at the UTRA Uu interface.
- NR positioning at the NR-Uu interface.
The following TTCN test specification and design considerations can be found in the present document:
- Test system architecture;
- Test models and ASP definitions;
- Test methods and usage of communication ports definitions;
- Test configurations;
- Design principles and assumptions;
- TTCN styles and conventions;
- Partial PIXIT proforma;
- Test suites in TTCN-2 and TTCN-3;
- The Test Suites designed and implemented in the present document are based on the test specifications in prose
in 3GPP TS 37.571-2 [3];
- The applicability of the individual test cases is specified in the test ICS proforma specification in
3GPP TS 37.571-3 [4].
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document unless the context in which the reference is made suggests a different Release is
relevant (information on the applicable release in a particular context can be found in e.g. test case title,
description or applicability, message description or content).
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 37.571-1: " User Equipment (UE) conformance specification for UE positioning; Part 1:
Conformance test specification".
[3] 3GPP TS 37.571-2: " User Equipment (UE) conformance specification for UE positioning; Part 2:
Protocol conformance".
[4] 3GPP TS 37.571-3: " User Equipment (UE) conformance specification for UE positioning; Part 3:
Implementation Conformance Statement (ICS)".
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[5] 3GPP TS 37.571-5: " User Equipment (UE) conformance specification for UE positioning; Part 5:
Test scenarios and assistance data".
[6] 3GPP TS 36.523-3: "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Packet
Core (EPC); User Equipment (UE) conformance specification; Part 3: Test suites".
[7] 3GPP TS 36.508: "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Packet
Core (EPC); Common test environments for User Equipment (UE) conformance testing".
[8] 3GPP TS 34.123-3: "User Equipment (UE) conformance specification; Part 3: Abstract test suite
(ATS)".
[9] 3GPP TS 34.108: "Common test environments for User Equipment (UE); Conformance testing".
[10] 3GPP TS 37.355: " LTE Positioning Protocol (LPP)".
[11] 3GPP TS 24.301: "Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS);
Stage 3".
[12] 3GPP TS 25.331: "Radio Resource Control (RRC); Protocol specification".
[13] 3GPP TS 24.080: "Mobile radio interface layer 3 supplementary services specification; Formats
and coding".
[14] 3GPP TS 29.002: "Mobile Application Part (MAP) specification".
[15] ITU-T Recommendation X.880: "Information technology - Remote Operations: Concepts, model
and notation".
[16] ITU-T Recommendation Q.773: "Transaction capabilities formats and encoding".
[17] ETSI ES 201 873-1: "Methods for Testing and Specification (MTS); The Testing and Test Control
Notation version 3; Part 1: TTCN-3 Core Language".
[18] 3GPP TS 34.109: "Terminal logical test interface; Special conformance testing functions".
[19] 3GPP TS 23.038: "Alphabets and language-specific information".
[20] ETSI TR 101 666 (V1.0.0): "Information technology; Open Systems Interconnection Conformance
testing methodology and framework; The Tree and Tabular Combined Notation (TTCN)
(Ed. 2++)".
[21] 3GPP TS 24.008: "Mobile radio interface Layer 3 specification; Core network protocols; Stage 3".
[22] 3GPP TS 23.032: "Universal Geographical Area Description (GAD)".
[23] 3GPP TS 36.211: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and
modulation".
[24] 3GPP TS 38.523-3: "5GS; User Equipment (UE) conformance specification; Part 3: Protocol Test
Suites".
[25] 3GPP TS 24.501: "Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3".
[26] 3GPP TS 36.331: "Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource
Control (RRC); Protocol specification".
[27] 3GPP TS 38.331: "NR; Radio Resource Control (RRC) protocol specification".
[28] 3GPP TS 38.508-1: "5GS; User Equipment (UE) conformance specification; Part 1: Common test
environment".
[29] 3GPP TS 38.211: "NR; Physical channels and modulation".
[30] 3GPP TS 38.355: "NR; Sidelink Positioning Protocol (SLPP); Protocol specification".
[31] 3GPP TS 24.587: "Vehicle-to-Everything (V2X) services in 5G System (5GS); Stage 3".
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3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1] apply.
3.2 Symbols
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] apply.
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] and the following apply:
ASP Abstract Service Primitive
4 A-GPS system architecture and test model
A-GPS signalling conformance tests are specified in TTCN-2. The system architecture and the test model are based on
3GPP TS 34.123-3 [8].
4.1 ATS and module structure
Refer to 3GPP TS 34.123-3 [8], clause 5.
4.2 Upper tester
Refer to 3GPP TS 34.123-3 [8], clause 7.3.5.1.
4.3 SV PCO
Refer to 3GPP TS 34.123-3 [8], clause 7.3.5.2.
4.4 A-GPS Primitives
Refer to 3GPP TS 34.123-3[8], clause 7.3.5.3.
4.5 Specific test suite operation for A-GPS testing
Refer to 3GPP TS 34.123-3 [8], clause 8.7.7.
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5 A-GNSS and LTE positioning system architecture
and test models
5.1 Test system architecture
5.1.1 General system architecture
Refer to 3GPP TS 36.523-3 [6], clause 4.1.1.
5.1.2 Component architecture
Each access technology (RAT) is hosted by a separate TTCN-3 parallel component (PTC):
- E-UTRA PTC;
- UTRA PTC.
The PTCs are controlled by the TTCN-3 positioning master test component (POS MTC) which:
- Is an extension of the MTC as defined in 3GPP TS 36.523-3 [6], clause 4.1.2.
- Controls the SS Positioning Simulator.
Figure 5.1.2-1 shows this component architecture for an E-UTRA and UTRA scenario.
AT/MMI commands
Upper Tester
POS MTC
TTCN-3
Synchronisation
Upper tester control
POS port control
Coordination
messages
UTRA
EUTRA
PTC PTC
A-GNSS
LTE positioning
TTCN
TTCN
POS Port E-UTRA E-UTRA UTRA Ports
Control Ports UE
Ports
UTRA
Control
Ports
Positioning
System Simulator
Simulator
Radio Interface
Satellite Signal
Figure 5.1.2-1: Component architecture for an E-UTRA and UTRA scenario

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The PTCs are allocated according to the following principles:
- For LTE positioning tests cases, the E-UTRA PTC is created.
- For LTE positioning CS fallback test cases, E-UTRA and UTRA PTCs are created.
- For UTRA A-GNSS test cases, the UTRA PTC is created.
5.1.2.1 Interfaces
A number of interfaces are taken into consideration.
POS MTC - PTC:
Common synchronisation of PTCs.
Positioning simulator command/data coordination messages.
Upper tester primitives.
POS MTC - System Interface:
Upper tester primitives.
POS MTC- Positioning Simulator:
Positioning simulator command and data primitives.
PTC - PTC:
Primitives containing information for IRAT handover.
PTC - System Interface:
Primitives containing peer-to-peer message.
Configuration primitives.
5.2 Test model
In order to perform the LTE positioning and A-GNSS tests, the Positioning Simulator shall have two basic functional
unites:
- Satellite simulator generating and broadcasting satellite signals.
- Assistance data source storing the data associated with the pre-defined GPS and GNSS test scenarios (see 3GPP TS
37.571-5 [5]).
This specification supports the following GNSS: GPS, Galileo, GLONASS and BDS.
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5.2.1 LTE GNSS test model
TTCN CODE
E-UTRA MTC
POS MTC
DRB SRB2-SRB0
Config/Control
POS Port
RR RC/RC/NNAA SS
EmEmuullaattoorr
Integrity
PDCP
Ciphering
RLRLCC
[A[AMM//UUMM//TTM]M]
Positioning
Simulator
MAMACC
PHPHYY
UE
Figure 5.2.1-1: E-UTRA Test model for LTE positioning GNSS testing

The LTE positioning test model consists of an SS E-UTRAN protocol stack and a positioning simulator. The SS E-
UTRA emulation part is the same as the model defined in 3GPP TS 36.523-3 [6].
The UE is configured in normal mode. On UE side Ciphering/Integrity (PDCP and NAS) is enabled. The tests are
performed on C-Plane.
The ASPs at POS Port are used to:
- Load a pre-defined test scenario into the positioning simulator.
- Start or stop generating and broadcasting satellite signals from the positioning simulator.
- Retrieve the GNSS assistance data from assistance data source.
Under the ASP commands, the upper tester loads or re-loads pre-defined GNSS test scenario to the positioning
simulator. The generated satellite signals shall simulate the GNSS environment as specified in 3GPP TS 37.571-2 [3],
clause 5.
The SS also sends the GNSS assistance data to the UE through LPP signalling (see 3GPP TS 37.355 [10]) to facilitate
the UE acquiring and tracking satellites. Such assistance data shall be consistent to within ±2 seconds with the satellite
signals generated (see 3GPP TS 37.571-2 [3], clause 5.2.1).
The assistance data source shall provide the assistance data consistent to +1/-0 second with the GNSS test scenario
currently running in the satellite simulator (i.e. the data shall be up to 1 second in advance of the scenario); this allows
for a further 2 seconds of latency in the SS. In case multiple satellite systems are configured in a test, the assistance data
are requested or retrieved in a single ASP command for all satellite systems.
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The UE positioning services are encoded in a TCAP [16] ROSE component [15] of the facility information element
[14] in the Supplement Service [13] conveyed in the NAS messages. The facility information element is encoded in
BER in TTCN referred to 3GPP TS 24.080 [13], clause 3.6.1 and 3GPP TS 29.002 [14], clause 17.1.1.
5.2.2 UTRA A-GNSS test model
TTCN CODE
POS MTC UTRAN PTC
Config/Control RAB SRB0-SRB4
POS Port
RRC (Integrity)
Emulator &
Direct transfer
RLC
Ciphering
Positioning
[AM/UM/TM]
Simulator
Ciphering MAC
PHY
UE
Figure 5.2.2-1: UTRA Test model for A-GNSS testing

The A-GNSS test model consists of an SS UTRAN protocol stack and a positioning simulator. The SS UTRA
emulation part is the same as the model defined in 3GPP TS 36.523-3 [6], clause 4.4.1.
The UE is configured in normal mode. Ciphering and Integrity (RRC) are enabled. The tests are performed on C-Plane.
The ASPs at POS Port are used to:
- Load a pre-defined test scenario into the positioning simulator.
- Start or stop generating and broadcasting satellite signals from the positioning simulator.
- Retrieve the GPS and GNSS assistance data from assistance data source.
Under the ASP commands, the upper tester loads or re-loads pre-defined GPS or GNSS test scenario to the positioning
simulator. The generated satellite signals shall simulate the A-GPS and A-GNSS environment as specified in
3GPP TS 37.571-2 [3], clause 4.2.
The SS also sends the GPS or GNSS assistance data to the UE through RRC signalling to facilitate the UE acquiring
and tracking satellites. Such assistance data shall be consistent to within ±2 seconds with the satellite signals generated
(see 3GPP TS 37.571-2 [3], clause 4.2).
The assistance data source shall provide the assistance data consistent to +1/-0 second with the GPS or GNSS test
scenario currently running in the satellite simulator (i.e. the data shall be up to 1 second in advance of the scenario); this
allows for a further 2 seconds of latency in the SS. In case multiple satellite systems are configured in a test, the
assistance data are requested or retrieved in a single ASP command for all satellite systems.
The UE positioning services are encoded in a TCAP [16] ROSE component [15] of the facility information element
[14] in the Supplement Service [13] conveyed in the NAS messages. The facility information element is encoded in
BER in TTCN referred to 3GPP TS 24.080 [13], clause 3.6.1 and 3GPP TS 29.002 [14], clause 17.1.1.
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5.3 ASP specifications
The E-UTRAN and UTRAN ASP definitions are specified according to 3GPP TS 36.523-3 [6], clause 6.
The positioning simulator ASP definitions are documented in annex C.
5.4 LTE OTDOA test model
TTCN CODE
E-UTRA PTC
Extension
DRB SRB2-SRB0
Config/Control
Config/Control
RRRR C/C/NASNAS
EmEmuullaattoorr
Integrity
PDCP
Ciphering
RLRLCC
[A[AMM//UUMM//TTMM]]
MAMACC
PHPHYY
UE
Figure 5.4-1: E-UTRA OTDOA test model

The LTE OTDOA test model consists of an SS E-UTRAN protocol stack. The SS E-UTRA emulation part is the same
as the model defined in 3GPP TS 36.523-3 [6] with an additional port to configure the antenna port 6 and the
Positioning Reference Signal (PRS) in the LTE cells. The extension of LTE ASPs is defined in annex C.
The simulated OTDOA environment is specified in 3GPP TS 37.571-2 [3], clause 5.2.2), cells are synchronous and
configured with the timing offset set to 0. The PRS is transmitted according to 3GPP TS 36.211 [23], clause 6.10.4.
The UE is configured in normal mode. On UE side Ciphering/Integrity (PDCP and NAS) is enabled. The tests are
performed on C-Plane.
The PRS signals are transmitted by the SS E-UTRAN, the assistance data are written in TTCN.
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3GPP TS 37.571-4 version 18.4.0 Release 18 15 ETSI TS 137 571-4 V18.4.0 (2026-04)
5.5 LTE ECID test model
The test model is referred to the LTE positioning test model defined in clause 5.2.1; except that no satellite signals are
required.
6 LTE indoor positioning system architecture and test
models
6.1 Test system architecture
6.1.1 General system architecture
Refer to 3GPP TS 36.523-3 [6], clause 4.1.1.
6.1.2 Component architecture
The same architecture as in 5.1.2 applies, excluding the UTRA PTC.

AT/MMI commands
Upper Tester
POS MTC
TTCN-3
Synchronisation
Upper tes ter control
POS port control
Coordination
messages
EUTRA
PTC
LTE positioning
TTCN
POS Port E-UTRA E-UTRA
Control UE
Ports
Ports
Indoor
Positioning
System Simulator
Simulator
Radio Interface
Positioning Signal
Figure 6.1.2-1: Component architecture for an E-UTRA scenario

ETSI
3GPP TS 37.571-4 version 18.4.0 Release 18 16 ETSI TS 137 571-4 V18.4.0 (2026-04)
6.1.2.1 Interfaces
Refer to 5.1.2.1.
6.2 Test model
6.2.1 LTE indoor positioning test model

Figure 6.2.1-1: E-UTRA Test model for LTE indoor positioning testing

The LTE Indoor Positioning test model consists of an SS E-UTRAN protocol stack and an Indoor Positioning
simulator. Depending on the Indoor Positioning Technology to be tested, the Indoor Positioning simulator will generate:
- MBS beacon signals, for MBS test cases;
- WLAN signals, for WLAN test cases;
- Bluetooth signals, for Bluetooth test cases.
- The Indoor Positioning simulator will be switched off for Sensor test cases.
The SS E-UTRA emulation part is the same as the model defined in 3GPP TS 36.523-3 [6].
The UE is configured in normal mode. On UE side Ciphering/Integrity (PDCP and NAS) is enabled. The tests are
performed on C-Plane.
The ASPs at POS Port are used to:
- Load a pre-defined test scenario into the Indoor Positioning simulator.
- Start or stop generating and broadcasting signals from the Indoor Positioning simulator.
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3GPP TS 37.571-4 version 18.4.0 Release 18 17 ETSI TS 137 571-4 V18.4.0 (2026-04)
- Retrieve the appropriate (MBS, WLAN, Sensor) assistance data from the assistance data source.
Under the ASP commands, the upper tester loads or re-loads pre-defined test scenario to the Indoor Positioning
simulator. The generated signals shall simulate the corresponding Indoor Positioning environment as specified in 3GPP
TS 37.571-2 [3], clause 5.
The SS also sends the appropriate assistance data to the UE through LPP signalling (see 3GPP TS 37.355 [10]) to
facilitate the UE acquisition of MBS Beacons or WLAN APs. For UE-based tests, the SS also sends the appropriate
assistance data to enable the UE to calculate its position for MBS or WLAN tests, or calculate altitude based on
barometric pressure sensor measurements.
The UE positioning services are encoded in a TCAP [16] ROSE component [15] of the facility information element
[14] in the Supplement Service [13] conveyed in the NAS messages. The facility information element is encoded in
BER in TTCN referred to 3GPP TS 24.080 [13], clause 3.6.1 and 3GPP TS 29.002 [14], clause 17.1.1.
6A LTE test models requiring GNSS support
Several LTE test models specified in TS 36.523-3 [6] require the presence of a GNSS emulation. Those are:
- V2X services: refer to TS 36.523-3 [6] clause 4.2.11
- Aerial UE: refer to TS 36.523-3 [6] clause 4.2.12
The positioning simulator shall be capable of generating and broadcasting the following GNSS: GPS, Galileo,
GLONASS and BDS.
The ASPs at POS Port for the both test models are used to:
- Load a pre-defined test scenario into the positioning simulator.
- Start or stop generating and broadcasting satellite signals from the positioning simulator.
The ASPs at POS Port for V2X services are additionally used to:
- Trigger the positioning simulator to move in the test scenario to the next geographical area or zone.
- Trigger the positioning simulator to switch on
...