ETSI TS 138 191 V19.2.0 (2026-04)

5G; NR; Ambient IoT device radio transmission and reception (3GPP TS 38.191 version 19.2.0 Release 19)

RTS/TSGR-0438191vj20

General Information

• Status: Not Published
• Technical Committee: 3GPP RAN 4 - Specification for radio performance
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 17-Apr-2026

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
NR;
Ambient IoT device radio transmission and reception
(3GPP TS 38.191 version 19.2.0 Release 19)

3GPP TS 38.191 version 19.2.0 Release 19 1 ETSI TS 138 191 V19.2.0 (2026-04)

Reference
RTS/TSGR-0438191vj20
Keywords
5G
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ETSI
3GPP TS 38.191 version 19.2.0 Release 19 2 ETSI TS 138 191 V19.2.0 (2026-04)
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ETSI
3GPP TS 38.191 version 19.2.0 Release 19 3 ETSI TS 138 191 V19.2.0 (2026-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 6
2 References . 6
3 Definitions, symbols and abbreviations . 6
3.1 Definitions . 6
3.2 Symbols . 6
3.3 Abbreviations . 7
4 General . 8
4.1 Relationship between minimum requirements and test requirements . 8
4.2 Applicability of minimum requirements . 8
5 Operating bands and channel arrangement . 8
5.1 General . 8
5.2 Operating bands . 8
5.3.1 R2D Channel bandwidth . 9
5.3.1.1 General . 9
5.3.1.2 R2D Transmission bandwidth . 9
5.3.1.3 Minimum guardband and R2D transmission bandwidth configuration . 10
5.3.1.4 RB alignment . 10
5.3.1.5 R2D channel bandwidth per operating band . 10
5.3.2 D2R Channel bandwidth . 11
5.3.2.1 General . 11
5.3.2.2 D2R Transmission bandwidth . 11
5.3.2.3 D2R channel bandwidth per operating band . 11
5.4 Channel arrangement . 11
5.4.1 R2D Channel raster . 11
5.4.1.1 AIoT-ARFCN and channel raster . 11
5.4.1.2 Channel raster to resource element mapping. 12
5.4.1.3 Channel raster entries for each operating band . 12
6 Transmitter characteristics . 13
6.0 General . 13
6.1 Backscatter power . 13
6.1.1 Device backscatter power . 13
6.2 Output RF spectrum emissions . 13
6.2.1 Out of band emissions. 13
6.2.1.1 General . 13
6.2.1.2 Spectrum emission mask . 13
6.2.2 Spurious emissions . 14
7 Receiver characteristics . 14
7.1 General . 14
7.2 Reference sensitivity power level . 14
7.2.1 General . 14
7.2.2 Reference sensitivity power level . 14
7.2.3 EIS partial sphere coverage . 15
7.3 Maximum input level . 15
8 OTA test characteristics . 16
8.1 General . 16
8.1.1 Testing bands . 16
8.2 Performance metrics . 16
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3GPP TS 38.191 version 19.2.0 Release 19 4 ETSI TS 138 191 V19.2.0 (2026-04)
8.2.1 Performance metric of Tx requirements . 16
8.2.2 Performance metric of Rx requirements . 16
8.3 Device positioning guidelines . 17
8.3.1 Free space . 17
8.4 Anechoic Chamber method . 17
8.4.1 General . 17
8.4.2 Backscattering measurement procedure . 18
8.4.3 Sensitivity measurement procedure . 18
8.4.4 Unwanted emission measurement procedure . 19
9 RRM . 20
9.1 Random access . 20
9.1.1 Introduction of random access . 20
9.1.2 Requirements for contention based random access . 20
9.1.2.1 Correct behaviour when transmitting Access Random ID message . 20
9.1.2.2 CBRA: Correct behaviour when receiving Random ID Response message . 20
9.1.2.3 CBRA: Correct behaviour when not receiving Random ID Response message . 20
9.1.3 Requirements for contention free access . 20
9.1.3.1 CFA: Correct behaviour when transmitting First D2R message . 20
9.2 D2R timing . 20
9.2.1 D2R transmit timing . 20
9.3 T . 20
D2R_min
9A RRM Test Case . 21
9A.1 Introduction . 21
9A.2 Test case . 21
9A.2.1 Test purpose and environment . 21
9A.2.2 Test procedure and parameters . 21
9A.2.3 Test requirements . 22
Annex A (normative): The test configuration for D2R power measurement. 24
Annex B (normative): Measurement channels . 25
B.1 General . 25
B.2 R2D reference measurement channels . 25
B.2.1 Fixed Reference Channels for reference sensitivity level (OOK) . 25
B.2.2 Fixed Reference Channels for maximum input level . 26
B.3 D2R reference measurement channels . 27
B.3.1 Fixed Reference Channels for transmitter characteristics . 27
Annex C (normative): Device coordinate system . 28
Annex D (normative): Estimation of Measurement uncertainty . 29
Annex E (informative): D2R channel bandwidth . 31
Annex F (informative): Change history . 32
History . 33

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3GPP TS 38.191 version 19.2.0 Release 19 5 ETSI TS 138 191 V19.2.0 (2026-04)
Foreword
This Technical Specification has been produced by the 3rd 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.

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3GPP TS 38.191 version 19.2.0 Release 19 6 ETSI TS 138 191 V19.2.0 (2026-04)
1 Scope
The present document establishes the minimum RF characteristics for Ambient IoT device.
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.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] Void
[3] 3GPP TS 38.291: "NR; Ambient IoT Physical layer".
[4] ITU-R Recommendation SM.329, "Unwanted emissions in the spurious domain".
[5] 3GPP TS 38.870: “Enhanced Over-the-Air (OTA) test methods for NR FR1 Total Radiated Power
(TRP) and Total Radiated Sensitivity (TRS)”.
[6] 3GPP TS 38.391: "NR; Ambient IoT Medium Access Control (MAC) protocol".

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] and the following apply. A
term defined in the present document takes precedence over the definition of the same term, if any, in 3GPP
TR 21.905 [1].
3.2 Symbols
For the purposes of the present document, the following symbols apply:
BW channel bandwidth
Channel
BW Transmission bandwidth, where BW = N x SCS x 12
Config Config RB
BW The minimum guard band defined in clause 5.3.1 for lowest assigned component carrier
GB,low
BW The minimum guard band defined in clause 5.3.1 for highest assigned component carrier
GB,high
Δf Separation between the channel edge frequency and the nominal -3 dB point of the measuring
filter closest to the carrier frequency
ΔF Global frequency raster granularity
Global
Δf f_offset minus half of the bandwidth of the measuring filter
max max
Δf Δ Frequency of Out Of Band emissionΔF Channel raster granularity
OOB Raster
F RF reference frequency on the channel raster, given in table 5.4.1.2-1
C
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3GPP TS 38.191 version 19.2.0 Release 19 7 ETSI TS 138 191 V19.2.0 (2026-04)
F The lowest frequency of the downlink operating band
DL,low
F The highest frequency of the downlink operating band
DL,high
f_offset Separation between the channel edge frequency and the centre of the measuring
f_offset The offset to the frequency Δf outside the downlink operating band
max OBUE
FOOB The boundary between the A-IoT out of band emission and spurious emission domains
F RF reference frequency
REF
F Offset used for calculating F
REF-Offs REF
F The lowest frequency of the uplink operating band
UL,low
The highest frequency of the uplink operating band
FUL,high
GB Minimum guard band defined in clause 5.3.1
Channel
n Physical resource block number
PRB
N Transmission bandwidth configuration, expressed in resource blocks
RB
N A-IoT Absolute Radio Frequency Channel Number (AIoT-ARFCN)
REF
N Offset used for calculating N
REF-Offs REF
P Conducted Reference Sensitivity power level
REFSENS
3.3 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] and the following apply. An
abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
3GPP TR 21.905 [1].
1SB Single sideband
2SB Double sideband
ACLR Adjacent Channel Leakage Ratio
ACS Adjacent Channel Selectivity
AWGN Additive White Gaussian Noise
A-IoT Ambient IoT
A-IoT RAN Ambient IoT Radio Access Network
BPSK Binary phase-shift keying
BS Base Station
BW Bandwidth
CFO Carrier-frequency offset
CP Cyclic prefix
CW Carrier-wave
CW2D Carrier-wave, or carrier-wave node, to device
D2R Device to reader
ED Envelope detector
E-UTRA Evolved UTRA
FAR False alarm rate
FEC Forward error-correction code
FR Frequency Range
FRC Fixed Reference Channel
IF Intermediate frequency
IoT Internet of Things
LPWA Low-power, wide-area
MCS Modulation and coding scheme
MDR Missed detection rate
OOK On-off keying
PDRCH Physical device-to-reader channel
PRDCH Physical reader-to-device channel
R2D Reader to device
RE Resource Element
REFSENS Reference Sensitivity
RF Radio frequency
RFID Radio frequency identification
R-TAS R2D timing acquisition signal
SCS Sub-Carrier Spacing
SER Sample error rate
SFO Sampling-frequency offset
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3GPP TS 38.191 version 19.2.0 Release 19 8 ETSI TS 138 191 V19.2.0 (2026-04)
UEM Unwanted Emissions Mask
ZIF Zero IF
4 General
4.1 Relationship between minimum requirements and test
requirements
The present document is a Single-RAT specification for NR Ambient IoT device, covering RF characteristics and
minimum performance requirements. Conformance to the present specification is demonstrated by fulfilling the test
requirements specified in the conformance specification TS 5xx [2].
The Minimum Requirements given in this specification make no allowance for measurement uncertainty. The test
specification TS 38.5xx [2] defines test tolerances. These test tolerances are individually calculated for each test. The
test tolerances are used to relax the minimum requirements in this specification to create test requirements. For some
requirements, including regulatory requirements, the test tolerance is set to zero.
The measurement results returned by the test system are compared - without any modification - against the test
requirements as defined in TS 38.5xx [2].
4.2 Applicability of minimum requirements
a) In this specification the Minimum Requirements are specified as general requirements and additional
requirements. Where the Requirement is specified as a general requirement, the requirement is mandated to be
met in all scenarios
b) For specific scenarios for which an additional requirement is specified, in addition to meeting the general
requirement, the Ambient IoT device is mandated to meet the additional requirements.
c) The spurious emissions power requirements are for the long-term average of the power. For the purpose of
reducing measurement uncertainty, it is acceptable to average the measured power over a period of time
sufficient to reduce the uncertainty due to the statistical nature of the signal

5 Operating bands and channel arrangement
5.1 General
The channel arrangements presented in this clause are based on the operating bands and channel bandwidths defined in
the present release of specifications.
NOTE: Other operating bands and channel bandwidths may be considered in future Releases.
5.2 Operating bands
Ambient IoT is designed to operate in the NR operating bands defined in Table 5.2-1.
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3GPP TS 38.191 version 19.2.0 Release 19 9 ETSI TS 138 191 V19.2.0 (2026-04)
Table 5.2-1: Ambient IoT operating bands
NR operating Uplink (UL) operating band Downlink (DL) operating band Duplex
band BS receive / UE transmit BS transmit / UE receive Mode
F – F (MHz) F  – F (MHz)
UL_low UL_high DL_low DL_high
n5 824 – 849 869 – 894 FDD
n8 880 – 915 925 – 960 FDD
n28 703 – 748 758 – 803 FDD
5.3 Channel bandwidth
5.3.1 R2D Channel bandwidth
5.3.1.1 General
The R2D channel bandwidth supports a single reader RF carrier in R2D link at the reader.
The relationship between the R2D channel bandwidth, the guardband and the transmission bandwidth is shown in figure
5.3.1.1-1.
Figure 5.3.1.1-1: Definition of channel bandwidth and transmission bandwidth configuration for one
reader channel
5.3.1.2 R2D Transmission bandwidth
The transmission bandwidth N for each R2D channel bandwidth and subcarrier spacing is specified in table 5.3.1.2.-
RB
1.
Table 5.3.1.2-1: R2D Transmission bandwidth configuration N for FR1
RB
SCS 200 400 600 800
(kHz)
kHz kHz kHz kHz
N N N N
RB RB RB RB
15 1 2 3 4
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3GPP TS 38.191 version 19.2.0 Release 19 10 ETSI TS 138 191 V19.2.0 (2026-04)
NOTE: Device Rx requirements are defined based on transmission bandwidth configuration specified in
table 5.3.1.2-1.
5.3.1.3 Minimum guardband and R2D transmission bandwidth configuration
The minimum guardband for each R2D channel bandwidth and SCS is specified in table 5.3.1.3-1.
Table 5.3.1.3-1: Minimum guardband (kHz) (FR1)
R2D CBW 200kHz 400kHz 600kHz 800kHz
Minimum guardband(kHz) 2.5 12.5 22.5 32.5

The number of RBs configured in any R2D channel bandwidth shall ensure that the minimum guardband specified in
this clause is met.
Figure 5.3.1.3-1: reader PRB utilization
5.3.1.4 RB alignment
For each R2D channel bandwidth, BS transmission bandwidth configuration must fulfil the minimum guardband
requirement specified in clause 5.3.1.3.
5.3.1.5 R2D channel bandwidth per operating band
The requirements in this specification apply to the combination of R2D channel bandwidths, SCS and operating bands
shown in table 5.3.1.5-1 for FR1. The transmission bandwidth configuration in table 5.3.1.2-1 shall be supported for
each of the R2D channel bandwidths within the BS capability. The R2D channel bandwidths are specified for the Tx
path.
Table 5.3.1.5-1: R2D channel bandwidths and SCS per operating band
Reader channel bandwidth
SCS
(kHz)
NR Bands
(kHz)
200 400 600 800
n5, n8, n28 15 200 400 600 800

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3GPP TS 38.191 version 19.2.0 Release 19 11 ETSI TS 138 191 V19.2.0 (2026-04)
5.3.2 D2R Channel bandwidth
5.3.2.1 General
The D2R channel bandwidth supports a single AIoT RF carrier in the D2R link at the device. From a BS perspective,
different device channel bandwidths may be supported within the same spectrum for backscattering from devices
connected to the BS.
From a device perspective, the device is allocated with its own device channel bandwidth. The device does not need to
be aware of the BS channel bandwidth.
5.3.2.2 D2R Transmission bandwidth
The transmission bandwidth for each D2R channel bandwidth is specified in table 5.3.2.3-1.
5.3.2.3 D2R channel bandwidth per operating band
The requirements specified in table 5.3.2.3-1 for device apply to all the operating bands in Table 5.2-1.
Table 5.3.2.3-1: Device D2R channel bandwidth
Device D2R channel bandwidth (kHz)
Nominal D2R transmission
Nominal Small frequency shift without SFO (kHz)
Bandwidth without SFO (kHz)
3.75 7.5 15 30 60 120 240 480 720

17 25 42 75 141 273 534 1065
33 50 83 149 281 545 1073
66 99 165 297 561 1089
120    132 198 330 594 1122
240     264 396 660 1188
480      528 792 1320
960       1056 1584
2880         3168
Table 5.3.2.3-2: Void
5.4 Channel arrangement
5.4.1 R2D Channel raster
5.4.1.1 AIoT-ARFCN and channel raster
The global frequency raster defines a set of RF reference frequencies F . The RF reference frequency is used in
REF
signalling to identify the position of RF channels and other elements. The granularity of the global frequency raster is
ΔF .
Global
RF reference frequencies are designated by an A-IoT Absolute Radio Frequency Channel Number (AIoT-ARFCN) in
the range [0…3279165] on the global frequency raster. The relation between the AIoT-ARFCN and the RF reference
frequency F in MHz is given by the following equation, where F and N are given in table 5.4.1.1-1 and
REF REF-Offs Ref-Offs
N is the AIoT-ARFCN.
REF
F = F + ΔF (N – N )
REF REF-Offs Global REF REF-Offs
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Table 5.4.1.1-1: AIoT-ARFCN parameters for the global frequency raster
Range of frequencies
ΔFGlobal (kHz) FREF-Offs (MHz) NREF-Offs Range of NREF
(MHz)
0 – 3000 5 0 0 0 – 599999
The channel raster defines a subset of RF reference frequencies that can be used to identify the RF channel position in
the uplink and downlink. The RF reference frequency for an RF channel maps to a resource element on the carrier. For
each operating band, a subset of frequencies from the global frequency raster are applicable for that band and forms a
channel raster with a granularity ΔF , which may be equal to or larger than ΔF .
Raster Global
The mapping between the channel raster and corresponding resource element is given in clause 5.4.1.2. The applicable
entries for each operating band are defined in clause 5.4.1.3.

5.4.1.2 Channel raster to resource element mapping
The mapping between the RF reference frequency on the channel raster and the corresponding resource element is given
in table 5.4.1.2-1 and can be used to identify the RF channel position. The mapping depends on the total number of RBs
that are allocated in the channel and applies to both UL and DL. The mapping must apply to at least one numerology
supported by the BS.
Table 5.4.1.2-1: Channel Raster to Resource Element Mapping

� ���2=0 � ���2=1
RB RB
0 6
Resource element index k
Physical resource block number n
PRB
   
N N
RB RB
n = n =
PRB   PRB  
2 2
   
k, n and N are as defined in TS 38.211 [3].
RB
PRB
5.4.1.3 Channel raster entries for each operating band
The RF channel positions on the channel raster in each NR operating band are given through the applicable NR-
ARFCN in table 5.4.1.3-1, using the channel raster to resource element mapping in clause 5.4.1.2.
th
Channel raster is defined with ΔF = 2 × ΔF . In this case every 2 NR-ARFCN within the operating band are
Raster Global
applicable for the channel raster within the operating band and the step size for the channel raster in Table 5.4.1.3-1 is
given as <2>.
Table 5.4.1.3-1: Applicable NR-ARFCN per operating band for enhanced channel raster
NR ΔF Uplink Downlink
Raster
operating (kHz) Range of N Range of N
REF REF
band (First – – Last) (First – – Last)
n5 10 164800 – <2> – 169800 173800 – <2> – 178800
n8 10 176000 – <2> – 183000 185000 – <2> – 192000
n28 10 140600 – <2> – 149600 151600 – <2> – 160600
NOTE 1: The channel numbers that designate carrier frequencies so close to the operating band
edges that the carrier extends beyond the operating band edge shall not be used. These
channel numbers shall also be such that the minimum guard band for each channel
bandwidth and SCS specified in Table 5.3.3-1 are met for carriers located at the upper or
lower edge of an operating band.

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3GPP TS 38.191 version 19.2.0 Release 19 13 ETSI TS 138 191 V19.2.0 (2026-04)
6 Transmitter characteristics
6.0 General
Unless otherwise stated, the transmitter characteristics are specified over the air (OTA).
6.1 Backscatter power
6.1.1 Device backscatter power
The backscatter power is defined as mean filtered power measured over the duration of the D2R signal, excluding the
power at the carrier frequency. The backscatter loss is defined as the difference between the input CW power at the
device antenna in dB scale to the backscatter power at the device antenna in dB scale.
The backscatter power is measured with the test metric of EIRP as specified in clause 8.2.1. The minimum requirement
on backscatter loss in Table 6.1.1.1-1 shall apply to all device D2R channel bandwidth defined in Table 5.3.2.3-1 and
shall be met with the test parameters defined in Annex A, at the peak antenna gain direction declared by the device
vendor.
Table 6.1.1.1-1: Maximum allowable backscatter loss
Operating bands Maximum backscatter loss (dB) CW power at the device antenna (dBm)
OOK 10 -27
BPSK 6
n5, n8, 28
OOK 15 -10
BPSK 11
6.2 Output RF spectrum emissions
6.2.1 Out of band emissions
6.2.1.1 General
The Out of band emissions are unwanted emissions immediately outside the assigned channel bandwidth resulting from
the modulation process and non-linearity in the transmitter but excluding spurious emissions.

6.2.1.2 Spectrum emission mask
The spectrum emission mask of the device applies to frequencies (Δf ) starting from the centre of the assigned D2R
OOB
channel bandwidth. For frequencies offset greater than Δf as specified in Table 6.2.1.2-1 the spurious requirements
OOB
in clause 6.2.2 are applicable.
The emission within Δf of a device shall be lower than the level specified in Table 6.2.1.2-1 compared to the D2R
OOB
backscatter power under same incident CW power level. The spectrum emission limits in Table 6.2.1.2-1 apply for all
D2R channel bandwidths. The requirement is verified with the test metric of EIRP and the incident CW power level at
the device set to -5 dBm. The test direction is the same as the backscatter output power as specified in clause 6.1.
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Table 6.2.1.2-1 Spectrum emission mask for device
Δf Spectrum emission limit Measurement
OOB
(MHz) (dBc) bandwidth
0.5* Nominal D2R
transmission
± 0.5*D2R CBW - FOOB 10
Bandwidth without
SFO
NOTE 1: FOOB is the OOB boundary frequency specified in Table 6.2.1.2-1.

6.2.2 Spurious emissions
Spurious emissions are emissions which are caused by unwanted transmitter effects but exclude out of band emissions
unless otherwise stated. The spurious emission limits are specified in terms of general requirements in line with SM.329
[4].
Unless otherwise stated, the spurious emission limits apply for the frequency ranges that are more than F (MHz) in
OOB
Table 6.2.2.2-1 from the centre of the D2R channel bandwidth. The spurious emission limits in Table 6.2.2.2-2 apply for
all D2R channel bandwidths. The requirement is verified with the test metric of EIRP under the incident CW power
level at the device is set to -5 dBm. The test direction is the same as the transmitter output power as specified in clause
6.1.
Table 6.2.2.2-1: Boundary between out of band and spurious emission domain for device
D2R Channel OOB boundary F (MHz)
OOB
bandwidth
D2R CBW<1.4 MHz max (500kHz, 10*D2R CBW)
D2R CBW≥1.4 MHz 7.5 MHz
Table 6.2.2.2-2: Requirement for spurious emissions limits
Frequency Range Maximum Level Measurement bandwidth NOTE
30 MHz ≤ f < 1000 MHz -36 dBm 100 kHz
1 GHz ≤ f < 5 GHz -30 dBm 1 MHz
5 GHz ≤ f < 12.75 GHz -30 dBm 1 MHz 1
NOTE 1: Applies for Band for which the upper frequency edge of the UL Band is greater than 1 GHz and less than or
equal to 2.55 GHz.
7 Receiver characteristics
7.1 General
Unless otherwise stated, the receiver characteristics are specified over the air (OTA). The power levels for all R2D
signals are defined assuming a 0dBi reference antenna located at the center of the quiet zone. The minimum
requirements on effective isotropic sensitivity (EIS) apply to two measurements, corresponding to DL signals in
orthogonal polarizations.
7.2 Reference sensitivity power level
7.2.1 General
The reference sensitivity power level REFSENS is defined as the EIS level at the centre of the quiet zone in the RX
gain peak direction, at which the successful detection rate shall meet or exceed the requirements for the specified
reference measurement channel.
7.2.2 Reference sensitivity power level
ETSI
3GPP TS 38.191 version 19.2.0 Release 19 15 ETSI TS 138 191 V19.2.0 (2026-04)
The successful detection rate shall be ≥ 90% of the reference measurement channels as specified in Annexes B.1, B.2
and B.3 with peak reference sensitivity specified in Table 7.2.2-1. The requirement is applied to all R2D channel
bandwidth defined in Table 5.3.1.5-1 and verified with the test metric of EIS at the peak antenna gain direction as
specified in clause 8.2.1.
Table 7.2.2-1: Reference sensitivity
Operating band Sensitivity Level REFSENS (dBm)
According to L1 -34
subclause 5.2
NOTE: The peak reference sensitivity is measured at the low, middle and high frequency of the supported
band(s), and the average value is verified against the requirement.

7.2.3 EIS partial sphere coverage
The reference measurement channels and detection criterion shall be as specified in clause 7.2.2
The maximum EIS measured over the partial sphere around the device is defined as the partial sphere coverage
requirement and is found in Table 7.2.3-1 below. The requirement is applied to all R2D channel bandwidth defined in
Table 5.3.1.5-1 and verified with the test metric of EIS as specified in clause 8.2.1.
Table 7.2.3-1: EIS partial sphere coverage
Operating band EIS (dBm) Angular width
According to -28.5 ±45 degrees
subclause 5.2
NOTE: The EIS partial sphere coverage requirement is verified at the middle frequency of the supported band(s).

7.3 Maximum input level
Maximum input level is defined as the maximum mean power received at the device peak antenna gain direction, at
which the specified success rate shall meet or exceed the minimum requirements for the specified reference
measurement channel. The successful detection rate shall be ≥ 90% of the reference measurement channels as specified
in Annex B with parameters specified in Table 7.3.-1.
Table 7.3-1: Maximum input level
Channel bandwidth (kHz)
R2D Parameter Units
200,400,600,800
Power in
Transmission
dBm
Bandwidth -4
Configuration
ETSI
3GPP TS 38.191 version 19.2.0 Release 19 16 ETSI TS 138 191 V19.2.0 (2026-04)
8 OTA test characteristics
8.1 General
8.1.1 Testing bands
The testing bands are based on operating bands as specified in sub-clause 5.2. The frequency ranges to be tested will be
all low, middle and high frequency ranges. The detailed testing parameters as the channel bandwidth, D2R and R2D
configuration for each band is defined by RAN5.
8.2 Performance metrics
8.2.1 Performance metric of Tx requirements
Transmitter power measurements shall be performed using the Effective Isotropic Radiated Power (EIRP) as the
measurement metric.
The EIRP is combined from θ and ϕ polarizations:
������,�� =���� ��,��| +���� ��,��| +���� ��,��| +���� ��,��|
� �� ��,�� � �� ��,�� � �� ��,�� � �� ��,��
� � � �
Where ���� and ���� are the EIRP in the corresponding θ and ϕ polarizations, �� and �� are the incident CW
� � � �
in the corresponding θ and ϕ polarizations,
st
For backscatter power measurement, the EIRP only contains the power of 1 sidebands within D2R channel bandwidth
and excludes power of CW.
8.2.2 Performance metric of Rx requirements
Receiver sensitivity measurements shall be performed using successful detection rate of R2D as the measurement
metric. The DUT’s receiver sensitivity corresponds to the minimum R2D signal power required to provide a successful
detection rate no less than 90% under the fixed reference channel (FRC) specified i
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