ETSI TR 136 903 V14.2.0 (2018-09)

LTE; Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Derivation of test tolerances for Radio Resource Management (RRM) conformance tests (3GPP TR 36.903 version 14.2.0 Release 14)

ETSI TR 136 903 V14.2.0 (2018-09)

Name:ETSI TR 136 903 V14.2.0 (2018-09)   Standard name:LTE; Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Derivation of test tolerances for Radio Resource Management (RRM) conformance tests (3GPP TR 36.903 version 14.2.0 Release 14)
Standard number:ETSI TR 136 903 V14.2.0 (2018-09)   language:English language
Release Date:27-Sep-2018   technical committee:3GPP RAN 5 - Mobile Terminal Conformance Testing (formely T1)
Drafting committee:   ICS number:
ETSI TR 136 903 V14.2.0 (2018-09)






TECHNICAL REPORT
LTE;
Evolved Universal Terrestrial Radio Access (E-UTRA)
and Evolved Universal Terrestrial
Radio Access Network (E-UTRAN);
Derivation of test tolerances
for Radio Resource Management (RRM) conformance tests
(3GPP TR 36.903 version 14.2.0 Release 14)



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3GPP TR 36.903 version 14.2.0 Release 14 1 ETSI TR 136 903 V14.2.0 (2018-09)



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3GPP TR 36.903 version 14.2.0 Release 14 2 ETSI TR 136 903 V14.2.0 (2018-09)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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
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server) which are, or may be, or may become, essential to the present document.
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Foreword
This Technical Report (TR) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
.
Modal verbs terminology
In the present document "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.
ETSI

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3GPP TR 36.903 version 14.2.0 Release 14 3 ETSI TR 136 903 V14.2.0 (2018-09)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 5
Introduction . 5
1 Scope . 6
2 References . 6
3 Definitions, symbols and abbreviations . 6
3.1 Definitions . 6
3.2 Symbols . 7
3.3 Abbreviations . 7
4 General Principles . 7
4.1 Principle of Superposition . 7
4.2 Sensitivity analysis . 7
4.3 Statistical combination of uncertainties . 7
4.4 Correlation between uncertainties . 8
4.4.1 Uncorrelated uncertainties . 8
4.4.2 Positively correlated uncertainties . 9
4.4.3 Negatively correlated uncertainties . 9
4.4.4 Treatment of uncorrelated uncertainties . 10
4.4.5 Treatment of positively correlated uncertainties with adverse effect . 10
4.4.6 Treatment of positively correlated uncertainties with beneficial effect . 10
4.4.7 Treatment of negatively correlated uncertainties . 10
5 Grouping of test cases defined in TS 36.521-3 . 11
5A Grouping of test cases defined in TS 37.571-1 . 14
6 Determination of Test System Uncertainties . 14
6.1 General . 14
6.2 Uncertainty figures . 14
7 Determination of Test Tolerances . 15
7.1 General . 15
Annex A: Derivation documents . 16
Annex B: Default uncertainties for test cases defined in TS 36.521-3 . 17
B.0 AWGN and Fading . 17
B.1 Group A: E-UTRA Intra-frequency mobility . 17
B.2 Group B: E-UTRA Inter-frequency mobility . 17
B.3 Group C: E-UTRA Intra-frequency UE reporting accuracy . 18
B.4 Group D: E-UTRA Inter-frequency UE reporting accuracy . 19
B.5 Group E: E-UTRA Random Access . 19
B.6 Group F: E-UTRA Transmit timing and Timing advance . 20
B.7 Group G: E-UTRA In-sync and Out-of-sync . 20
B.8 Group H: E-UTRA to UTRA Inter-RAT mobility . 21
B.9 Group I: E-UTRA to GSM Inter-RAT mobility. 21
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3GPP TR 36.903 version 14.2.0 Release 14 4 ETSI TR 136 903 V14.2.0 (2018-09)
Annex C: Default uncertainties for test cases defined in TS 37.571-1 . 23
Annex D: Change History . 23
History . 39


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3GPP TR 36.903 version 14.2.0 Release 14 5 ETSI TR 136 903 V14.2.0 (2018-09)
Foreword
rd
This Technical Report 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
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3GPP TR 36.903 version 14.2.0 Release 14 6 ETSI TR 136 903 V14.2.0 (2018-09)
1 Scope
The present document specifies a general method used to derive Test Tolerances for Radio Resource Management tests,
and establishes a system for relating the Test Tolerances to the measurement uncertainties of the Test System.
The test cases which have been analysed to determine Test Tolerances are included as .zip files.
The present document is applicable from Release 8 up to the release indicated on the front page of the present Terminal
conformance specifications.
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] ETSI ETR 273-1-2: "Improvement of radiated methods of measurement (using test sites) and
evaluation of the corresponding measurement uncertainties; Part 1: Uncertainties in the
measurement of mobile radio equipment characteristics; Sub-part 2: Examples and annexes".
[3] 3GPP TS 34.121-1: "Terminal conformance specification, Radio transmission and reception
(FDD), Release 8".
[4] 3GPP TS 36.521-1: "User Equipment (UE) conformance specification, Radio transmission and
reception Part 1: conformance testing, Release 8".
[5] 3GPP TS 36.521-3: "User Equipment (UE) conformance specification, Radio transmission and
reception Part 3: Radio Resource Management (RRM) conformance testing, Release 8".
[6] 3GPP TS 36.141: "E-UTRA Base Station (BS) conformance testing, Release 8"
[7] 3GPP TS 36.211: "E-UTRA Physical Channels and Modulation, Release 8"
[8] 3GPP TS 37.571-1: “Universal Terrestrial Radio Access (UTRA) and Evolved UTRA (E-UTRA)
and Evolved Packet Core (EPC); User Equipment (UE) conformance specification for UE
positioning; Part 1: Terminal conformance”.
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in TR 21.905 [1] apply. A term defined in the
present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].
Other definitions used in the present document are listed in 3GPP TS 36.521-3 [5] or 3GPP TS 36.141 [6].
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3GPP TR 36.903 version 14.2.0 Release 14 7 ETSI TR 136 903 V14.2.0 (2018-09)
3.2 Symbols
Symbols used in the present document are listed in 3GPP TR 21.905 [1], 3GPP TS 36.521-3 [5] or 3GPP TS 36.141 [6].
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in TR 21.905 [1] apply. An abbreviation defined in
the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [1].
Other abbreviations used in the present document are listed in 3GPP TS 36.521-3 [5] or 3GPP TS 36.141 [6].
4 General Principles
4.1 Principle of Superposition
For multi-cell tests there are several cells each generating various Physical channels. In general cells are combined
along with AWGN, so the signal and noise seen by the UE may be determined by more than one cell.
Since several cells may contribute towards the overall power applied to the UE, a number of test system uncertainties
affect the signal and noise seen by the UE. The aim of the superposition method is to vary each controllable parameter
of the test system separately, and to establish its effect on the critical parameters as seen by the UE receiver. The
superposition principle then allows the effect of each test system uncertainty to be added, to calculate the overall effect.
The contributing test system uncertainties shall form a minimum set for the superposition principle to be applicable.
4.2 Sensitivity analysis
A change in any one channel level or channel ratio generated at source does not necessarily have a 1:1 effect at the UE.
The effect of each controllable parameter of the test system on the critical parameters as seen by the UE receiver shall
therefore be established. As a consequence of the sensitivity scaling factors not necessarily being unity, the test system
uncertainties cannot be directly applied as test tolerances to the critical parameters as seen by the UE.
EXAMPLE: In many of the tests described, the Ês / I is one of the critical parameters at the UE. Scaling
ot
factors are used to model the sensitivity of the Ês / I to each test system uncertainty. When the
ot
scaling factors have been determined, the superposition principle then allows the effect of each test
system uncertainty to be added, to give the overall variability in the critical parameters as seen at
the UE.
There are often constraints on several parameters at the UE. The aim of the sensitivity analysis, together with the
acceptable test system uncertainties, is to ensure that the variability in each of these parameters is controlled within the
limits necessary for the specification to apply. The test has then been conducted under valid conditions.
4.3 Statistical combination of uncertainties
The acceptable uncertainties of the test system are specified as the measurement uncertainty tolerance interval for a
specific measurement that contains 95 % of the performance of a population of test equipment, in accordance with
3GPP TS 36.521-3 [5] clause F.1. In the RRM tests covered by the present document, the Test System shall enable the
stimulus signals in the test case to be adjusted to within the specified range, with an uncertainty not exceeding the
specified values.
The method given in the present document combines the acceptable uncertainties of the test system, to give the overall
variability in the critical parameters as seen at the UE. Since the process does not add any new uncertainties, the method
of combination should be chosen to maintain the same tolerance interval for the combined uncertainty as is already
specified for the contributing test system uncertainties.
The basic principle for combining uncertainties is in accordance with ETR 273-1-2 [2]. In summary, the process
requires 3 steps:
a) Express the value of each contributing uncertainty as a one standard deviation figure, from knowledge of its
numeric value and its distribution.
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3GPP TR 36.903 version 14.2.0 Release 14 8 ETSI TR 136 903 V14.2.0 (2018-09)
b) Combine all the one standard deviation figures as root-sum-squares, to give the one standard deviation value for
the combined uncertainty.
c) Expand the combined uncertainty by a coverage factor, according to the tolerance interval required.
Provided that the contributing uncertainties have already been obtained using this method, using a coverage factor of 2,
further stages of combination can be achieved by performing step b) alone, since steps a) and c) simply divide by 2 and
multiply by 2 respectively.
The root-sum-squares method is therefore used to maintain the same tolerance interval for the combined uncertainty as
is already specified for the contributing test system uncertainties. In some cases where correlation between contributing
uncertainties has an adverse effect, the method is modified in accordance with clause 4.4.5 of the present document.
In each analysis, the uncertainties are assumed to be uncorrelated, and are added result root-sum-square unless
otherwise stated.
The combination of uncertainties is performed using dB values for simplicity. It has been shown that using dB
uncertainty values gives a slightly worse combined uncertainty result than using linear values for the uncertainties. The
analysis method therefore errs on the safe side.
4.4 Correlation between uncertainties
The statistical (root-sum-square) addition of uncertainties is based on the assumption that the uncertainties are
independent of each other. For realisable test systems, the uncertainties may not be fully independent. The validity of
the method used to add uncertainties depends on both the type of correlation and on the way in which the uncertainties
affect the test requirements.
Clauses 4.4.1 to 4.4.3 give examples to illustrate different types of correlation.
Clauses 4.4.4 to 4.4.7 show how the scenarios applicable to multi-cell RRM tests are treated.
4.4.1 Uncorrelated uncertainties
The graph shows an example of two test system uncertainties, A and B, which affect a test requirement. Each sample
from a population of test systems has a specific value of error in parameter A, and a specific value of error in parameter
B. Each dot on the graph represents a sample from a population of test systems, and is plotted according to its error
values for parameters A and B.
Error in
parameter B
Error in
parameter A

Figure 4.4.1.1: Example of two test system uncertainties affecting a test requirement

It can be seen that a positive value of error in parameter A, for example, is equally likely to occur with either a positive
or a negative value of error in parameter B. This is expected when two parameters are uncorrelated, such as two
uncertainties which arise from different and unrelated parts of the test system.
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3GPP TR 36.903 version 14.2.0 Release 14 9 ETSI TR 136 903 V14.2.0 (2018-09)
4.4.2 Positively correlated uncertainties
The graph shows an example of two test system uncertainties, A and B, which affect a test requirement. Each sample
from a population of test systems has a specific value of error in parameter A, and a specific value of error in parameter
B. Each dot on the graph represents a sample from a population of test systems, and is plotted according to its error
values for parameters A and B.
Error in
parameter B
Error in
parameter A

Figure 4.4.2.1: Example of two test system uncertainties affecting a test requirement

It can be seen that a positive value of error in parameter A, for example, is more likely to occur with a positive value of
error in parameter B and less likely to occur with a negative value of error in parameter B. This can occur when the two
uncertainties arise from similar parts of the test system, or when one component of the uncertainty affects both
parameters in a similar way.
In an extreme case, if the error in parameter A and the error in parameter B came from the same sources of uncertainty,
and no others, the dots would lie on a straight line of slope +1.
4.4.3 Negatively correlated uncertainties
The graph shows an example of two test system uncertainties, A and B, which affect a test condition. Each sample from
a population of test systems has a specific value of error in parameter A, and a specific value of error in parameter B.
Each dot on the graph represents a sample from a population of test systems, and is plotted according to its error values
for parameters A and B.
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3GPP TR 36.903 version 14.2.0 Release 14 10 ETSI TR 136 903 V14.2.0 (2018-09)
Error in
parameter B
Error in
parameter A

Figure 4.4.3.1: Example of two test system uncertainties affecting a test condition

It can be seen that a positive value of error in parameter A, for example, is more likely to occur with a negative value of
error in parameter B and less likely to occur with a positive value of error in parameter B. This effect can theoretically
occur, and is included for completeness, but is unlikely in a practical test system.
4.4.4 Treatment of uncorrelated uncertainties
If two uncertainties are uncorrelated, they are added statistically in the analysis. Provided that each uncertainty is
already expressed as an expanded uncertainty with coverage factor 2, the contributing uncertainties are added root-sum-
squares to give a combined uncertainty which also has coverage factor 2, and the 95% tolerance interval is maintained.
This is the default assumption.
4.4.5 Treatment of positively correlated uncertainties with adverse effect
If two test system uncertainties are positively correlated, and if they affect the value of a critical parameter in the same
direction, the combined effect may be greater than predicted by adding the contributing uncertainties root-sum-squares.
In this scenario the two uncertainties are added worst-case in the analysis. Provided that each uncertainty is already
expressed as an expanded uncertainty with coverage factor 2, the combined uncertainty will cover a 95% tolerance
interval even when the two contributing uncertainties are fully correlated. If the two contributing uncertainties are less
than fully correlated, the combined uncertainty will cover a tolerance interval greater than 95%.
4.4.6 Treatment of positively correlated uncertainties with beneficial effect
If two test system uncertainties are positively correlated, and if they affect the value of a critical parameter in opposite
directions, the combined effect will be less than predicted by adding the contributing uncertainties root-sum-squares.
In this scenario the two uncertainties are added statistically in the analysis. Provided that each uncertainty is already
expressed as an expanded uncertainty with coverage factor 2, the combined uncertainty will cover a 95% tolerance
interval when the two contributing uncertainties are uncorrelated. If the two contributing uncertainties are positively
correlated, the combined uncertainty will cover a tolerance interval greater than 95%.
4.4.7 Treatment of negatively correlated uncertainties
Negatively correlated uncertainties are excluded by the assumptions. This has been agreed as an acceptable restriction
on practical test systems, as the mechanisms which produce correlation generally arise from similarities between two
parts of the test system, and therefore produce positive correlation.
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3GPP TR 36.903 version 14.2.0 Release 14 11 ETSI TR 136 903 V14.2.0 (2018-09)
5 Grouping of test cases defined in TS 36.521-3
The Test cases are grouped from the viewpoint of efficiently defining the uncertainties and test tolerances. Tests in the
same group generally have the same type of uncertainties, given in more detail in Annex B.
A group of test cases having significant differences from those already listed, in respect of uncertainties and test
tolerance analysis, will require a new row in the Table.
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3GPP TR 36.903 version 14.2.0 Release 14 12 ETSI TR 136 903 V14.2.0 (2018-09)
Table 5-1: Test case groups for test tolerance analysis
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3GPP TR 36.903 version 14.2.0 Release 14 13 ETSI TR 136 903 V14.2.0 (2018-09)
Group E-UTRA E-UTRA E-UTRA E-UTRA E-UTRA Comments
FDD TDD FDD/TDD FDD Inter- TDD Inter-
RAT RAT
A 4.2.1 4.2.2  Two cell LTE intra
5.1.1 5.1.2 2 or 3 time periods
6.1.1 6.1.3 Various number of sub-tests
8.1.1 Some tests have fading
8.1.2 8.2.1
8.1.3 8.2.2
B 4.2.3 4.2.6  Two or three cell LTE inter
5.1.3 5.1.4 2 or 3 time periods
5.1.5 5.1.6 Some tests have fading
6.1.2 6.1.4
8.3.1
8.3.2
8.4.1
8.4.2
8.3.3
8.4.3
8.11.1 8.11.2
C 9.1.1.1 9.1.2.1  Two cell LTE intra
9.1.1.2 9.1.2.2 3 sub-tests
9.2.1.1 9.2.2.1 RSRP, RSRQ
D 9.1.3.1 9.1.4.1  Two cell LTE inter
9.1.3.2 9.1.4.2 2 or 3 sub-tests
9.2.3.1 9.2.4.1 RSRP, RSRQ
9.2.3.2 9.2.4.2
E 6.2.1 6.2.3  One cell LTE
6.2.2 6.2.4 1 time period
Various number of sub-tests
Level, timing
F 7.1.1 7.1.2  One cell LTE
7.2.1 7.2.2 Various number of time
periods
Various number of sub-tests
Timing only
G 7.3.1 7.3.3  One cell LTE
7.3.2 7.3.4 Various number of time
7.3.5 7.3.7 periods
7.3.6 7.3.8 Various number of sub-tests
H  4.3.1.1 One cell LTE or two cell
4.3.4.2 LTE inter frequency
4.3.1.2 one UTRA cell
4.3.4.1 Various number of time
4.3.1.3 periods
4.3.4.3 Various number of sub-tests
4.3.2 Some tests have fading
4.3.3
5.2.1 5.2.2
5.2.5 5.2.4
5.2.7
5.2.10
8.5.1 8.6.1
8.5.2
8.7.3
8.5.3

8.7.2
8.9.1
9.3.1 9.3.2
9.4.1 9.4.2
I  4.4.1 4.4.2 One cell LTE or two cell
5.2.3 5.2.6 LTE inter frequency
5.2.8 5.2.9 one GSM cell
8.8.1 8.10.1 2 or 3 time periods
8.8.2 8.10.2 No fading
J 8.3.7 8.4.7
...

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