8 Radiated performance requirements

37.145-23GPPActive Antenna System (AAS) Base Station (BS) conformance testingPart 2: radiated conformance testingRelease 17TS

8.1 General

Radiated performance requirements specify the ability of the OTA AAS BS to correctly demodulate radiated signals in various propagation conditions and configurations.

The demodulation requirements for an OTA AAS BS are limited to two OTA demodulations branches as described in clause 8.1.1, and are the same as non-AAS BS demodulation requirements specified for:

Single RAT UTRA operation in TS 25.104 [2] clause 8 for FDD operation,

Single RAT E-UTRA operation in TS 36.104 [4], clauses 8.2 – 8.4 (for PUSCH, PUCCH and PRACH) and 8.6 – 8.7 (for subslot-PUSCH and SPUCCH),

MSR operation in TS 37.105 [6], based on references to the single RAT requirements in TS 25.104 [2] and TS 36.104 [4].

8.1.1 OTA demodulation branches

OTA performance requirements are only specified for up to 2 demodulation branches.

If the OTA AAS BS uses polarization diversity and has the ability to maintain isolation between the signals for each of the demodulation branches, then OTA performance requirements can be tested for up to two demodulation branches (i.e. 1TX-1RX or 1TX-2RX test setup). When tested for two demodulation branches, each demodulation branch maps to one polarization.

If the OTA AAS BS does not use polarization diversity then OTA performance requirements can only be tested for a single demodulation branch (i.e. 1TX-1RX test setup).

8.2 Radiated performance requirements for MSR

For OTA AAS BS in single RAT UTRA operation, minimum requirements for radiated demodulation performance are specified in clause 8.3.

For OTA AAS BS in single RAT E-UTRA operation, minimum requirements for radiated demodulation performance are specified in clause 8.4.

For OTA AAS BS in NR operation, minimum requirements for radiated demodulation performance are specified in clause 8.5.

NOTE: Radiated performance requirements for MSR BS are applicable to the multi-RAT of single RAT operation, but tested only in single RAT configuration.

8.3 Radiated performance requirements for UTRA FDD

8.3.1 General

Radiated performance requirements for single RAT UTRA operation in FDD are specified for the fixed reference channels (FRC) and propagation conditions defined in TS 25.104 [2] annex A and annex B, respectively. The requirements only apply to those FRCs that are supported by the OTA AAS BS.

Unless stated otherwise, radiated performance requirements apply for a single carrier only. Performance requirements for a BS supporting DC-HSUPA or DB-DC-HSUPA are defined in terms of single carrier requirements. The requirements in clause 8.3 shall be met with the transmitter(s) ON.

NOTE: In normal operating conditions the transceiver units are configured to transmit and receive at the same time. The transmitter unit(s) associated with the RIB may be OFF for some of the tests in clause 8.

In the referenced conducted test requirements from TS 25.141 [10] the method to test describes connection to one or a number of BS antenna connectors. When applying these methods to the OTA AAS BS, connection shall be made to the RIB, based on one or two OTA demodulation branches.

In the referred UTRA specifications and in this clause, the term "BS with RX diversity" refers to performance requirements for two demodulation branches, and the term "BS without RX diversity" refers to performance requirements for one demodulation branch. For "BS with RX diversity", only the BS performance requirements with Rx diversity apply, otherwise only the BS performance requirements without Rx diversity apply.

For testing purposes, there is one demodulation branch per active polarization assumed. In tests performed with signal generators a synchronization signal may be provided, from the BS to the signal generator, to enable correct timing of the wanted signal.

The Eb/N0 used is defined as:

Where:

is the received total energy of DPDCH, DPCCH, S-DPCCH, HS-DPCCH, E-DPDCH, S-E-DPDCH, E-DPCCH and S-E-DPCCH per PN chip per demodulation branch from all branches

is the total one-sided noise power spectral density due to all noise sources

is the number of chips per frame

is the number of information bits in DTCH excluding CRC bits per frame

All Bit Error Ratio (BER) and Block Error ratio (BLER) measurements shall be carried out according to the general rules for statistical testing defined in ITU-T Recommendation O.153 [30] and TS 25.141 [10], annex C.

If external BLER measurement is not used then the internal BLER calculation shall be used instead. When internal BLER calculation is used, the requirements of the verification test according to TS 25.141 [10] clause 8.6 shall be met in advance.

Table 8.3.1-1: Summary of AAS BS performance targets for single RAT UTRA operation in FDD

Physical channel

Measurement channel

Static

Multi-path

Case 1

Multi-path

Case 2

Multi-path

Case 3

Moving

Birth /

Death

High Speed Train (Note)

Performance metric

12.2 kbps

BLER<10-2

BLER<10-2

BLER<10-2

BLER<10-2

BLER <10-2

BLER <10-2

BLER <10-2

DCH

64 kbps

BLER<

10-1,10-2

BLER<

10-1, 10-2

BLER<

10-1,10-2

BLER <

10-1, 10-2,10-3

BLER <

10-1,10-2

BLER <

10-1,10-2

144 kbps

BLER<

10-1,10-2

BLER<

10-1,10-2

BLER<

10-1,10-2

BLER <

10-1, 10-2,10-3

384 kbps

BLER<

10-1,10-2

BLER<

10-1,10-2

BLER<

10-1,10-2

BLER <

10-1, 10-2,10-3

NOTE: Optional condition, not applicable for all BSs.

8.3.2 Definitions and applicability

Definitions of radiated performance requirements in single RAT UTRA operation in FDD and their applicability are the same as defined in TS 25.141 [10], in requirement’s specific "Definition and applicability" clauses within 8.2 ‑ 8.13 clauses.

The following limitation apply for the radiated performance requirements in single RAT UTRA operation in FDD:

– All the radiated performance requirements referred from TS 25.141 [10] are subject to 2Rx limitation in the OTA test setup, as captured in clause 8.1.1.

– If the OTA AAS BS does not use polarisation diversity then performance requirements only apply to a single demodulation branch (i.e. 1TX-1RX test setup).

– If the OTA AAS BS uses polarisation diversity and has the ability to maintain isolation between the performance requirements signals for each of the demodulation branches, then performance requirements can be applied to up to two demodulation branches (i.e. 1TX-2RX test setups).

NOTE: for the list of BS demodulation requirements which were found to be feasible in OTA test setup with the above 2Rx limitation, refer to TR 37.941 [38].

– For FRC8 in TS 25.104 [2] the non E-DPCCH boosting and E-DPCCH boosting requirement only apply for the option supported by the OTA AAS BS.

– Performance of signalling detection for 4C-HSDPA HS-DPCCH test shall be performed only for the BS supporting 4C-HSDPA.

– Performance of signalling detection for 8C-HSDPA HS-DPCCH test shall be performed only for the BS supporting 8C-HSDPA.

– The performance requirements for the high speed train scenarios defined in TS 25.104 [2] are optional.

8.3.3 Minimum requirements

Minimum requirements for radiated performance requirements in single RAT UTRA operation in FDD are the same as defined in TS 25.104 [2], in requirement’s specific "Minimum requirement" clauses within 8.2 ‑ 8.12 clauses, subject to limitations listed in clause 8.3.2.

8.3.4 Test purposes

Test purposes for the radiated performance requirements in single RAT UTRA operation in FDD are the same as defined in TS 25.141 [10], in requirement’s specific "Test purpose" clauses within clauses 8.2 ‑ 8.13.

The radiated test shall verify the OTA AAS BS receiver’s ability to achieve requirement’s specific performance metric under defined propagation conditions emulated in OTA test chamber, for a given Eb/N0 (or Ec/N0).

8.3.5 Method of test

8.3.5.1 Initial conditions

Initial conditions of radiated performance requirements in single RAT UTRA operation in FDD are the same as defined in TS 25.141 [10], in requirement’s specific "Initial conditions" clauses within 8.2 ‑ 8.13 clauses, with the exception, that instead of connecting the BS tester(s) directly to antenna connector(s), either a single or two polarizations should be transmitted via test antenna(s) in the OTA chamber, where each polarization represents a demodulation branch.

The initial conditions for the radiated performance requirements in single RAT UTRA operation in FDD are generalized as follows:

Test environment: normal, see annex G.2.

RF channels to be tested: B, M and T; see TS 25.141 [10], clause 4.8.

Direction to be tested: OTA REFSENS receiver target reference direction (see table 4.10-1, D11.30).

8.3.5.2 Procedure

1) Place the OTA AAS BS with its manufacturer declared coordinate system reference point in the same place as calibrated point in the test system, as shown in annex D.3.

2) Align the manufacturer declared coordinate system orientation of the OTA AAS BS with the test system.

3) Set the OTA AAS BS in the declared direction to be tested.

4) Connect the BS tester generating the wanted signal, multipath fading simulators and/or AWGN generators (depending on the required OTA test procedure) to a test antenna via a combining network in OTA test setup, as shown in annex D.3.

5) Apply the conducted performance test procedure appropriate to the requirement as described in clause 8 of TS 25.141 [10]. Instead of connection via an antenna connector, one of the RX antenna signals should be transmitted on each polarization of the test antenna(s).

6) The characteristics of the wanted signal shall be configured according to the corresponding UL reference measurement channel defined in annex A in TS 25.141 [10], and according to additional test parameters listed in respective conducted performance test procedure in TS 25.141 [10].

a. For RACH requirements: configure test signal generator to sends a preamble according to the test signal pattern defined for RACH in TS 25.141 [10].

7) The multipath fading emulators shall be configured according to the corresponding channel model defined in TS 25.141 [10], annex D.

8) Adjust the test signal mean power so the calibrated radiated signal level at the BS receiver is as specified in requirement’s specific clause 8 of TS 25.141 [10].

a. For DCH requirements: Adjust the test signal mean power so the calibrated radiated Eb/N0value at the BS receiver is as specified in requirement’s specific clause 8 of TS 25.141 [10]. To achieve the specified Eb/N0, the ratio of the wanted signal level relative to the AWGN signal should be adjusted to: 10 * Log10(Rb / 3.84 * 106) + Eb/N0 [dB].

b. For RACH requirements: Adjust the test signal mean power so the calibrated radiated Eb/N0 (or Ec/N0) value at the BS receiver is as specified in requirement’s specific clause 8 of TS 25.141 [10].

i. For RACH preamble detection in static propagation, multipath fading case 3, or in high speed train conditions: To achieve the specified Ec/N0, the ratio of the wanted signal level (of the preamble part) relative to the AWGN signal at the BS receiver should be adjusted to: Ec/N[dB].

ii. For Demodulation of RACH message in static propagation conditions, multipath fading case 3, or in high speed train conditions: To achieve the specified Ec/N0, the ratio of the wanted signal level (of the message part) relative to the AWGN signal at the BS receiver should be adjusted to: 10 * Log10(TB / (TTI * 3.84 * 106)) + Eb/N[dB].

c. For HS-DPCCH: Adjust the test signal mean power so the calibrated radiated Ec/N0 value at the BS receiver is as specified in requirement’s specific clause 8 of TS 25.141 [10]. To achieve the specified Ec/N0, the ratio of the wanted signal level relative to the AWGN signal at the BS input should be adjusted to: Ec/N[dB].

The power level for the transmission may be set such that the AWGN level at the RIB is equal to the AWGN level quoted in the test procedure of TS 25.141 [10] minus ΔOTAREFSENS. Example of the AWGN levels for the UTRA FDD requirements, with the ΔOTAREFSENS correction are presented in table 8.4.5.2-1.

Table 8.3.5.2-1: AWGN power level at the BS input for UTRA FDD requirements

BS class

AWGN power level

Wide Area

– 84 – ΔOTAREFSENS [dBm] / 3.84 MHz

Medium Range

– 74 – ΔOTAREFSENS [dBm] / 3.84 MHz

Local Area

– 70 – ΔOTAREFSENS [dBm] / 3.84 MHz

While signal power adjustment, reassure that the Eb/N0 (or Ec/N0) at the BS receiver is not impacted by the noise floor.

9) If RX diversity is not supported, ensure the polarisation match is achieved among test antenna(s) and the OTA AAS BS under test, in order to maximize the power at the BS receiver.

10) For reference channels applicable to the BS, measure the appropriate performance metric for the requirement as described in clause 8 of TS 25.141 [10].

8.3.6 Test requirements

Test requirements of radiated performance requirements in single RAT UTRA operation in FDD are the same as defined in TS 25.141 [10], in requirement’s specific "Test requirement" clauses within 8.2 ‑ 8.13 clauses, with the exception that shall be derived based on the OTA test procedure, as in clause 8.3.5.2.

Applicability of radiated test requirements is subject to limitations listed in clause 8.3.2.

In the referenced test requirements in this clause, the term "number of RX antennas" should be replaced by one if a single polarization is transmitted or by two if two polarizations are transmitted.

NOTE: If the above Test Requirement differs from the Minimum Requirement then the Test Tolerance applied for this test is non-zero. The Test Tolerance for this test and the explanation of how the Minimum Requirement has been relaxed by the Test Tolerance is given in annex C.

8.4 Radiated performance requirements for E-UTRA

8.4.1 General

Radiated performance requirements for single RAT E-UTRA operation are specified for the fixed reference channels (FRC) and propagation conditions defined in TS 36.104 [4] annex A and annex B, respectively. The requirements only apply to those FRCs that are supported by the OTA AAS BS.

Unless stated otherwise, radiated performance requirements apply for a single carrier only. Radiated performance requirements for an OTA AAS BS in E-UTRA operation supporting carrier aggregation are defined in terms of single carrier requirements.

In the referred E-UTRA specification TS 36.104 [4], the term "RX antennas" refers to demodulation branches (and not physical antennas).

Conformance requirements can only be tested for 1 or 2 demodulation branches depending on the number of polarizations supported by the BS, with the required SNR /SINR (in case of E-UTRA demodulation requirements), or required Eb/N0 (in case of UTRA FDD demodulation requirements) applied separately per polarization.

Only 2RX BS performance requirements apply when OTA AAS BS supports and is tested with dual polarizations, except where requirements are defined with 1RX only (e.g. HST) where the requirements shall be tested with single polarization.

NOTE: OTA AAS BS can support more than 2 demodulation branches, however OTA conformance testing can only be performed for 1 or 2 demodulation branches.

For tests in clause 8.4 the transmitters may be OFF.

The performance requirements for High Speed Train conditions are optional.

The performance requirements for UL timing adjustment scenario 2 are optional.

In tests performed with signal generators a synchronization signal may be provided, from the BS to the signal generator, to enable correct timing of the wanted signal.

For E-UTRA performance requirements the SNR used in this clause is specified based on a single carrier and defined as:

SNR = S / N

Where:

S is the total signal energy in the subframe.

N is the noise energy in a bandwidth corresponding to the transmission bandwidth over the duration of a subframe.

For enhanced E-UTRA performance requirements type A, the SINR used in this clause is specified based on a single carrier and defined as:

SINR = S / N’

Where:

S is the total signal energy in the subframe.

N’ is the summation of the received energy of the strongest interferers explicitly defined in a test procedure plus the white noise energy N, in a bandwidth corresponding to the transmission bandwidth over the duration of a subframe. The respective energy of each interferer relative to N’ is defined by its associated DIP value.

In the referenced conducted test requirements from TS 36.141 [12] the method to test describes connection to one or a number of BS antenna connectors. When applying these methods to the OTA AAS BS, connection shall be made to the RIB, based on one or two OTA demodulation branches.

8.4.2 Definitions and applicability

Definitions of radiated performance requirements in single RAT E-UTRA operation and their applicability are the same as defined in TS 36.141 [12], in requirement’s specific "Definition and applicability" clauses within 8.2 ‑ 8.4 clauses.

The following limitation apply for the radiated performance requirements in single RAT E-UTRA operation:

– All the radiated performance requirements referred from TS 36.141 [12] are subject to 2Rx limitation in the OTA test setup, as captured in clause 8.1.1.

– If the OTA AAS BS does not use polarisation diversity then performance requirements only apply to a single demodulation branch (i.e. 1TX-1RX test setup).

– If the OTA AAS BS uses polarisation diversity and has the ability to maintain isolation between the performance requirements signals for each of the demodulation branches, then performance requirements can be applied to up to two demodulation branches (i.e. 1TX-2RX test setups).

NOTE: for the list of BS demodulation requirements which were found to be feasible in OTA test setup with the above 2Rx limitation, refer to TR 37.941 [38].

– A test for a specific channel bandwidth is only applicable if the BS supports it. For a BS supporting multiple channel bandwidths only the tests for the lowest and the highest channel bandwidths supported by the BS are applicable.

– The performance requirements for High Speed Train conditions are optional.

– The performance requirements for UL timing adjustment scenario 2 are optional.

– Performance requirements for coverage enhancements are applicable only to the AAS BS supporting coverage enhancement configured with CEModeA. This applies to the following requirements:

– Requirements for PUSCH supporting coverage enhancement

– Requirements for PUSCH supporting Cat-M1 UEs

– PUCCH performance requirements for supporting Cat-M1 UEs

– PRACH missed detection, Cat-M1 mode

– The enhanced performance requirements apply to AAS BS supporting the enhanced performance requirements type A and/or type B.

– Performance requirements for NB-IoT are not applicable to AAS BS.

For PUSCH performance requirements, the FRCs for the throughput performance metric derivation are listed in TS 36.141 [12], annex A.

8.4.3 Minimum requirements

Minimum requirements for radiated performance requirements in single RAT E-UTRA operation are the same as defined in TS 36.104 [4], in requirement’s specific "Minimum requirement" clauses within 8.2 ‑ 8.4 (for PUSCH, PUCCH and PRACH) and 8.6 – 8.7 (for subslot-PUSCH and SPUCCH), subject to limitations listed in clause 8.4.2.

8.4.4 Test purposes

Test purposes for the radiated performance requirements in single RAT E-UTRA operation are the same as defined in TS 36.141 [12], in requirement’s specific "Test purpose" clauses within clauses 8.2 ‑ 8.4 (for PUSCH, PUCCH and PRACH) and 8.6 – 8.7 (for subslot-PUSCH and SPUCCH).

The radiated test shall verify the OTA AAS BS receiver’s ability to achieve requirement’s specific performance metric under defined propagation conditions emulated in OTA test chamber, for a given SNR (or SINR).

8.4.5 Method of test

8.4.5.1 Initial conditions

Initial conditions of radiated performance requirements in single RAT E-UTRA operation are the same as defined in TS 36.141 [12], in requirement’s specific "Initial conditions" clauses within 8.2 ‑ 8.4 and 8.6 – 8.7, with the exception, that instead of connecting the BS tester(s) directly to antenna connector(s), either a single or two polarizations should be transmitted via test antenna(s) in the OTA chamber, where each polarization represents a demodulation branch.

The initial conditions for the radiated performance requirements in single RAT E-UTRA operation are generalized as follows:

Test environment: normal, annex G.2.

RF channels to be tested: M; see TS 36.141 [12], clause 4.7.

Direction to be tested: OTA REFSENS receiver target reference direction (see table 4.10-1, D11.30).

8.4.5.2 Procedure

1) Place the OTA AAS BS with its manufacturer declared coordinate system reference point in the same place as calibrated point in the test system, as shown in annex D.3.

2) Align the manufacturer declared coordinate system orientation of the OTA AAS BS with the test system.

3) Set the OTA AAS BS in the declared direction to be tested.

4) Connect the BS tester generating the wanted signal, interference signal(s), multipath fading simulators and/or AWGN generators (depending on the required OTA test procedure) to a test antenna via a combining network in OTA test setup, as shown in annex D.3.

a. For enhanced performance requirements and for ACK missed detection for multi user PUCCH format 1a: Interconnect attenuators for relative power setting purposes for all transmitting branches (wanted signal and all interferers, separately).

5) Apply the conducted performance test procedure appropriate to the requirement as described in clause 8 of TS 36.141 [12]. Instead of connection via an antenna connector, one of the RX antenna signals should be transmitted on each polarization of the test antenna(s).

6) The characteristics of the wanted/interfering signal shall be configured according to the corresponding UL reference measurement channel defined in annex A in TS 36.141 [12], and according to additional test parameters listed in respective conducted performance test procedure in TS 36.141 [12]. In case of PUCCH requirements, the characteristics of the wanted signal shall be configured according to TS 36.211 [28].

7) The multipath fading emulators shall be configured according to the corresponding channel model defined in TS 36.141 [12], annex B.

8) Adjust the test signal mean power so the calibrated radiated SNR (or SINR) value at the BS receiver is as specified in requirement’s specific clause 8 of TS 36.141 [12], and that the SNR (or SINR) at the BS receiver is not impacted by the noise floor.

The power level for the transmission may be set such that the AWGN level at the RIB is equal to the AWGN level quoted in the test procedure of TS 36.141 [12] minus ΔOTAREFSENS. Examples of the AWGN levels for the E-UTRA PUSCH as well as for the PUCCH and PRACH requirements, with the ΔOTAREFSENS correction are presented in table 8.4.5.2-1 and table 8.4.5.2-2, respectively.

Table 8.4.5.2-1: AWGN power level at the BS input for PUSCH requirements

Channel bandwidth [MHz]

AWGN power level

1.4

-92.7 – ΔOTAREFSENS [dBm] / 1.08 MHz

3

-88.7 – ΔOTAREFSENS [dBm] / 2.7 MHz

5

-86.5 – ΔOTAREFSENS [dBm] / 4.5 MHz

10

-83.5 – ΔOTAREFSENS [dBm] / 9 MHz

15

-81.7 – ΔOTAREFSENS [dBm] / 13.5 MHz

20

-80.4 – ΔOTAREFSENS [dBm] / 18 MHz

Table 8.4.5.2-2: AWGN power level at the BS input for PUCCH and PRACH requirements

Channel bandwidth [MHz]

AWGN power level

1.4

-89.7 – ΔOTAREFSENS [dBm] / 1.08 MHz

3

-85.7 – ΔOTAREFSENS [dBm] / 2.7 MHz

5

-83.5 – ΔOTAREFSENS [dBm] / 4.5 MHz

10

-80.5 – ΔOTAREFSENS [dBm] / 9 MHz

15

-78.7 – ΔOTAREFSENS [dBm] / 13.5 MHz

20

-77.4 – ΔOTAREFSENS [dBm] / 18 MHz

9) If RX diversity is not supported, ensure the polarisation match is achieved among test antenna(s) and the OTA AAS BS under test, in order to maximize the power at the BS receiver.

10) For reference channels applicable to the BS, measure the appropriate performance metric for the requirement as described in clause 8 of TS 36.141 [12].

8.4.6 Test requirements

Test requirements of radiated performance requirements in single RAT E-UTRA operation are the same as defined in TS 36.141 [12], in requirement’s specific "Test requirement" clauses within 8.2 ‑ 8.4 and 8.6 – 8.7, with the exception that shall be derived based on the OTA test procedure, as in clause 8.4.5.2.

Applicability of radiated test requirements is subject to limitations listed in clause 8.4.2.

In the referenced test requirements in this clause, the term "number of RX antennas" should be replaced by one if a single polarization is transmitted or by two if two polarizations are transmitted.

NOTE: If the above Test Requirement differs from the Minimum Requirement then the Test Tolerance applied for this test is non-zero. The Test Tolerance for this test and the explanation of how the Minimum Requirement has been relaxed by the Test Tolerance is given in annex C.

8.5 Radiated performance requirements for NR

8.5.1 General

Radiated performance requirements specify the ability of the OTA AAS BS to correctly demodulate radiated signals in various conditions and configurations. Radiated performance requirements are specified at the RIB.

Radiated performance requirements for NR operation are specified for the fixed reference channels (FRC) and propagation conditions defined in TS 38.104 [36] annex A and annex G, respectively. The requirements only apply to those FRCs that are supported by the OTA AAS BS.

The radiated performance requirements for OTA AAS BS are limited to two OTA demodulation branches as described in clause 8.1.1. Conformance requirements can only be tested for 1 or 2 demodulation branches depending on the number of polarizations supported by the BS, with the required SNR applied separately per polarization.

NOTE 1: The BS can support more than 2 demodulation branches, however OTA conformance testing can only be performed for 1 or 2 demodulation branches.

Unless stated otherwise, radiated performance requirements apply for a single carrier only. Radiated performance requirements for NR operation supporting carrier aggregation are defined in terms of single carrier requirements.

For OTA AAS BS in FDD operation the requirements in clause 8 shall be met with the transmitter units associated with the RIB in the operating band turned ON.

NOTE 2: In normal operating conditions, transceivers in FDD operation are configured to transmit and receive at the same time. The associated transmitter unit(s) may be OFF for some of the tests as specified in TS 38.141-2 [34].

In tests performed with signal generators a synchronization signal may be provided, from the BS to the signal generator, to enable correct timing of the wanted signal.

Conformance requirements can only be tested for 1 or 2 demodulation branches depending on the number of polarizations supported by the BS, with the required SNR applied separately per polarization.

Only 2RX BS performance requirements apply when OTA AAS BS supports and is tested with dual polarizations.

NOTE 3: OTA AAS BS can support more than 2 demodulation branches, however OTA conformance testing can only be performed for 1 or 2 demodulation branches.

The SNR used in this clause is specified based on a single carrier and defined as:

SNR = S / N

Where:

S is the total signal energy in a slot on a RIB.

N is the noise energy in a bandwidth corresponding to the transmission bandwidth over the duration of a slot on a RIB.

8.5.2 Definitions and applicability

Definitions of radiated performance requirements in NR operation and their applicability are the same as defined in TS 38.141-2 [34], in requirement’s specific "Definition and applicability" clauses within 8.2 ‑ 8.4.

The following limitation apply for the radiated performance requirements in NR operation:

– All the radiated performance requirements referred from TS 38.141-2 [34] are subject to 2RX limitation in the OTA test setup, as captured in clause 8.1.1.

– If the OTA AAS BS does not use polarisation diversity then performance requirements only apply to a single demodulation branch (i.e. 1TX-1RX test setup).

– If the OTA AAS BS uses polarisation diversity and has the ability to maintain isolation between the performance requirements signals for each of the demodulation branches, then performance requirements can be applied to up to two demodulation branches (i.e. 1TX-2RX test setups).

– A test for a specific channel bandwidth is only applicable if the BS supports it. For a BS supporting multiple channel bandwidths only the tests for the lowest and the highest channel bandwidths supported by the BS are applicable.

For PUSCH performance requirements, the FRCs for the throughput performance metric derivation are listed in TS 38.141-2 [34], annex A.

8.5.3 Minimum requirements

Minimum requirements for radiated performance requirements in NR operation are the same as defined in TS 38.104 [36], in requirement’s specific "Minimum requirement" clauses within 8.2 ‑ 8.4, subject to limitations listed in clause 8.5.2.

8.5.4 Test purposes

Test purposes for the radiated performance requirements in NR operation are the same as defined in TS 38.141-2 [34], in requirement’s specific "Test purpose" clauses within 8.2 ‑ 8.4.

The radiated test shall verify the OTA AAS BS receiver’s ability to achieve requirement’s specific performance metric under defined propagation conditions emulated in OTA test chamber, for a given SNR.

8.5.5 Method of test

8.5.5.1 Initial conditions

Initial conditions of radiated performance requirements in NR operation are the same as defined in TS 38.141-2 [34], in requirement’s specific "Initial conditions" clauses within 8.2 ‑ 8.4.

A single or two polarizations should be transmitted via test antenna(s) in the OTA chamber, where each polarization represents a demodulation branch.

The initial conditions for the radiated performance requirements in NR operation are generalized as follows:

Test environment: normal, annex G.2.

RF channels to be tested: M; see TS 38.141-2 [34], clause 4.9.

Direction to be tested: OTA REFSENS receiver target reference direction (see table 4.10-1, D11.30).

8.5.5.2 Procedure

1) Place the OTA AAS BS with its manufacturer declared coordinate system reference point in the same place as calibrated point in the test system, as shown in annex D.3.

2) Align the manufacturer declared coordinate system orientation of the OTA AAS BS with the test system.

3) Set the OTA AAS BS in the declared direction to be tested.

4) Connect the BS tester generating the wanted signal, interference signal(s), multipath fading simulators and/or AWGN generators (depending on the required OTA test procedure) to a test antenna via a combining network in OTA test setup, as shown in annex D.3.

5) Apply the performance test procedure appropriate to the requirement as described in clause 8 of TS 38.141-2 [34]. One of the RX antenna signals should be transmitted on each polarization of the test antenna(s).

6) The characteristics of the wanted/interfering signal shall be configured according to the corresponding UL reference measurement channel defined in annex A in TS 38.141-2 [34], and according to additional test parameters listed in respective performance test procedures. In case of PUCCH requirements, the characteristics of the wanted signal shall be configured according to TS 38.211 [36].

7) The multipath fading emulators shall be configured according to the corresponding channel model defined in TS 38.141-2 [34], annex J.

8) Adjust the test signal mean power so the calibrated radiated SNR value at the BS receiver is as specified in requirement’s specific clause 8 of TS 38.141-2 [34], and that the SNR at the BS receiver is not impacted by the noise floor.

The power level for the transmission may be set such that the AWGN level at the RIB is set according to the respective PUSCH, PUCCH, or PRACH test procedures of TS 38.141-2 [34].

Table 8.2.1.4.2-2: Void

9) If RX diversity is not supported, ensure the polarisation match is achieved among test antenna(s) and the OTA AAS BS under test, in order to maximize the power at the BS receiver.

10) For reference channels applicable to the BS, measure the appropriate performance metric for the requirement as described in clause 8 of TS 38.141-2 [34].

8.5.6 Test requirements

Test requirements of radiated performance requirements in NR operation are the same as defined in TS 38.141-2 [34], in requirement’s specific "Test requirement" clauses within 8.2 ‑ 8.4.

Applicability of radiated test requirements is subject to limitations listed in clause 8.5.2.

NOTE: If the above Test Requirement differs from the Minimum Requirement then the Test Tolerance applied for this test is non-zero. The Test Tolerance for this test and the explanation of how the Minimum Requirement has been relaxed by the Test Tolerance is given in annex C.

Annex A (normative):
Test system characterization

The radiated measurement methods for AAS BS conformance testing were described in TR 37.941 [38], including descriptions of their limitations and testing applicability.

Annex B (normative):
Calibration

The radiated measurement methods for AAS BS conformance testing were described in TR 37.941 [38]. Calibration stage description was covered for each of the identified Test Systems in the measurement’s procedure description, which covered two distinct stages: calibration stage and measurement stage. This has been separately covered for transmitter and for receiver requirements.

Annex C (informative):
Test tolerances and derivation of test requirements