8.5 Performance requirements for Narrowband IoT

36.1413GPPBase Station (BS) conformance testingEvolved Universal Terrestrial Radio Access (E-UTRA)Release 17TS

8.5.1 Performance requirements for NPUSCH format 1

8.5.1.1 Definition and applicability

The performance requirement of NPUSCH format 1 is determined by a minimum required throughput for a given SNR. The required throughput is expressed as a fraction of maximum throughput for the FRCs listed in Annex A. The performance requirements assume HARQ re-transmissions.

The tests for 3.75KHz subcarrier spacing are applicable to the base stations supporting 3.75 kHz subcarrier spacing requirements. The tests for single-subcarrier/multi-subcarrier of 15KHz subcarrier spacing are applicable to the base stations supporting the number of subcarriers of 15 kHz subcarrier spacing requirements.

The tests defined in Table 8.5.1.5-4 are applicable to the base stations supporting two HARQ processes, multiple TBs scheduling with interleaved transmission when multiple TBs are scheduled.

8.5.1.2 Minimum Requirement

The minimum requirement is in TS 36.104 [2] subclause 8.5.1.

8.5.1.3 Test Purpose

The test shall verify the receiver’s ability to achieve the throughput under multipath fading propagation conditions for a given SNR.

8.5.1.4 Method of test

8.5.1.4.1 Initial Conditions

Test environment: Normal, see subclause D.2.

RF channels to be tested: M; see subclause 4.7.

1) Connect the BS tester generating the wanted signal, multipath fading simulators and AWGN generators to all BS antenna connectors for diversity reception via a combining network as shown in Annex I.3.2.

8.5.1.4.2 Procedure

1) Adjust the AWGN generator, according to the channel bandwidth, defined in Table 8.5.1.4.2-1.

Table 8.5.1.4.2-1: AWGN power level at the BS input

Channel bandwidth [KHz]

AWGN power level

200

-100.5dBm /180KHz

2) The characteristics of the wanted signal shall be configured according to the corresponding UL reference measurement channel defined in annex A and the test parameters in Table 8.5.1.4.2-2.

Table 8.5.1.4.2-2: Test parameters for testing NPUSCH format 1

Parameter

unit

Value

Maximum number of HARQ transmissions

4

RV sequences

RV0, RV2

3) The multipath fading emulators shall be configured according to the corresponding channel model defined in annex B.

4) Adjust the equipment so that required SNR specified in tables 8.5.1.5-1 to 8.5.1.5-3 is achieved at the BS input.

5) The signal generator sends a test pattern with the pattern outlined in Figure 8.5.1.4.2-1. For each of the reference channels in Table 8.5.1.5-1 to 8.5.1.5-3 applicable for the base station, measure the throughput, according to annex E.

3485DA75-BDE8-48D2-B041-78E08F81D465

Figure 8.5.1.4.2-1: Test signal pattern for NPUSCH format 1 demodulation tests

8.5.1.5 Test Requirement

The throughput measured according to subclause 8.5.1.4.2 shall not be below the limits for the SNR levels specified in Table 8.5.1.5-1 for 3.75KHz subcarrier spacing tests, not be below the limits for the SNR levels specified in Table 8.5.1.5-2 for 15KHz subcarrier spacing with single subcarrier tests and not be below the limits for the SNR levels specified in Table 8.5.1.5-3 for 15KHz subcarrier spacing with the supported number of subcarrier tests.

Table 8.5.1.5-1 Required SNR for NPUSCH format 1 test, 200KHz Channel Bandwidth, 3.75KHz subcarrier spacing, 1Tx

Number of TX antennas

Number of RX antennas

Subcarrier spacing

Number of allocated subcarriers

Propagation conditions and correlation matrix (Annex B)

FRC
(Annex A)

Repetition number

Fraction of maximum throughput

SNR

[dB]

1

2

3.75KHz

1

ETU 1Hz Low

A16-1

1

70%

-1.3

16

70%

-8.6

64

70%

-11.6

Table 8.5.1.5-2 Required SNR for NPUSCH format 1 test, 200KHz Channel Bandwidth, 15KHz subcarrier spacing, single subcarrier, 1Tx

Number of TX antennas

Number of RX antennas

Subcarrier spacing

Number of allocated subcarriers

Propagation conditions and correlation matrix (Annex B)

FRC
(Annex A)

Repetition number

Fraction of maximum throughput

SNR

[dB]

1

2

15KHz

1

ETU 1Hz Low

A16-2

1

70%

-1.5

16

70%

-8.2

64

70%

-12

Table 8.5.1.5-3 Required SNR for NPUSCH format 1 test, 200KHz Channel Bandwidth, 15KHz subcarrier spacing, multiple subcarriers, 1Tx

Number of TX antennas

Number of RX antennas

Subcarrier spacing

Number of allocated subcarriers

Propagation conditions and correlation matrix (Annex B)

FRC
(Annex A)

Repetition number

Fraction of maximum throughput

SNR

[dB]

1

2

15KHz

3

ETU 1Hz Low

A16-3

2

70%

-2.4

16

70%

-7.5

64

70%

-10.8

6

ETU 1Hz Low

A16-4

2

70%

0

16

70%

-6.2

64

70%

-9.9

12

ETU 1Hz Low

A16-5

2

70%

-0.1

16

70%

-5.8

64

70%

-9.5

Table 8.5.1.5-4: Required SNR for NPUSCH format 1 with two HARQ processes and multiple TBs with interleaved transmission

Number of TX antennas

Number of RX antennas

Subcarrier spacing

Number of allocated subcarriers

Propagation conditions and correlation matrix (Annex B)

FRC
(Annex A)

Repetition number

Fraction of maximum throughput

SNR

[dB]

1

2

15KHz

12

ETU 1Hz Low

A16-6

64

70%

-13.3

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 G.

8.5.2 ACK missed detection for NPUSCH format 2

8.5.2.1 Definition and applicability

The performance requirement of NPUSCH format 2 for ACK missed detection is determined by the two parameters: probability of false detection of the ACK and the probability of detection of ACK. The performance is measured by the required SNR at probability of detection equal to 0.99. The probability of false detection of the ACK shall be 0.01 or less.

The probability of false detection of the ACK is defined as a conditional probability of erroneous detection of the ACK when input is only noise.

The probability of detection of ACK is defined as conditional probability of detection of the ACK when the ACK was sent per NPUSCH format 2 transmission when the signal is present.

The tests for 3.75KHz subcarrier spacing are applicable to the base stations supporting 3.75 KHz subcarrier spacing requirements. The tests for 15KHz subcarrier spacing are applicable to the base stations supporting 15KHz subcarrier spacing requirements.

8.5.2.2 Minimum Requirement

The minimum requirement is in TS 36.104 [2] subclause 8.5.2.1 and 8.5.2.2.

8.5.2.3 Test purpose

The test shall verify the receiver’s ability to detect ACK under multipath fading propagation conditions for a given SNR.

8.5.2.4 Method of test

8.5.2.4.1 Initial Conditions

Test environment: Normal, see subclause D.2.

RF channels to be tested: M; see subclause 4.7

1) Connect the BS tester generating the wanted signal, multipath fading simulators and AWGN generators to all BS antenna connectors for diversity reception via a combining network as shown in Annex I.3.2.

8.5.2.4.2 Procedure

1) Adjust the AWGN generator, according to the channel bandwidth defined in Table 8.5.2.4.2-1.

Table 8.5.2.4.2-1: AWGN power level at the BS input

Channel bandwidth [KHz]

AWGN power level

200

-100.5dBm /180KHz

2) The characteristics of the wanted signal shall be configured according to TS 36.211 [12].

3) The multipath fading emulators shall be configured according to the corresponding channel model defined in Annex B.

4) Adjust the equipment so that the SNR specified in tables 8.5.2.5-1 to 8.5.2.5-2 is achieved at the BS input during the ACK transmissions.

5) The signal generator sends a test pattern with the pattern outlined in figure 8.5.2.4.2-1. The following statistics are kept: the number of ACKs falsely detected in the idle periods and the number of missed ACKs. Each falsely detected ACK transmission in the idle periods is accounted as one error for the statistics of false ACK detection, and each missed ACK transmission per NPUSCH format 2 transmisson is accounted as one error for the statistics of missed ACK detection.

EA1D09FA-C399-4281-A9D0-19EC7F381A50

Figure 8.5.2.4.2-1: Test signal pattern for NPUSCH format 2 demodulation tests

8.5.2.5 Test Requirement

The fraction of falsely detected ACKs shall be less than 1% and the fraction of correctly detected ACKs shall be larger than 99% for the SNR listed in Table 8.5.2.5-1 and Table 8.5.2.5-2.

Table 8.5.2.5-1 Required SNR for NPUSCH format 2 test, 200KHz Channel Bandwidth, 3.75KHz subcarrier spacing, 1Tx

Number of TX antennas

Number of RX antennas

Propagation conditions and

correlation matrix (Annex B)

Number of allocated subcarriers

Subcarrier spacing

Repetition number

SNR [dB]

1

2

EPA 5 Low

1

3.75KHz

1

7.6

16

-4.7

64

-10.3

Table 8.5.2.5-2 Required SNR for NPUSCH format 2 test, 200KHz Channel Bandwidth, 15KHz subcarrier spacing, 1Tx

Number of TX antennas

Number of RX antennas

Propagation conditions and

correlation matrix (Annex B)

Number of allocated subcarriers

Subcarrier spacing

Repetition number

SNR [dB]

1

2

EPA 5 Low

1

15KHz

1

6.9

16

-3.3

64

-8.9

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 G.

8.5.3 Performance requirements for NPRACH

8.5.3.1 Definition and applicability

The performance requirement of NPRACH for preamble detection is determined by two parameters: the total probability of false detection of the preamble (Pfa) and the probability of detection of the preamble (Pd). The performance is measured for the required SNR

– at probability of Pd which shall not be smaller than 99% and

– at probability of Pfa which shall not be larger than 0.1%.

Pfa is defined as a conditional total probability of erroneous detection of the preamble (i.e. erroneous detection from any detector) when input is only noise.

Pd is defined as conditional probability of detection of the preamble when the signal is present. The erroneous detection consists of several error cases – detecting different preamble than the one that was sent, not detecting a preamble at all or correct preamble detection but with the wrong timing estimation. A timing estimation error occurs if the estimation error of the timing of the strongest path is larger than 3.646 us. The strongest path for the timing estimation error refers to the strongest path in the power delay profile.

The performance requirements for TDD are optional and only valid for base stations supporting TDD.

The parameters of NPRACH test preambles are listed in Table 8.5.3.1-1.

Table 8.5.3.1-1 NPRACH Test Parameters

Parameter

Value

Value

Narrowband physical layer cell identity

0

0

Initial subcarrier index

0

0

nprach-Periodicity (ms)

160 for preamble format 2, otherwise 80

[1280] for preamble format 2, otherwise 320

nprach-SubcarrierOffset

0

0

numRepetitionsPerPreambleAttempt

8

32

nprach-NumSubcarriers

36 for FDD preamble format 2, otherwise 12

Uplink-downlink configuration for TDD

1

Special subframe configuration for TDD

7

8.5.3.2 Minimum Requirement

The minimum requirement is in TS 36104 [2] subclause 8.5.3.1.1 and 8.5.3.2.1.

8.5.3.3 Test purpose

The test shall verify the receiver’s ability to detect NPRACH preamble under multipath fading propagation conditions for a given SNR.

8.5.3.4 Method of test

8.5.3.4.1 Initial Conditions

Test environment: Normal, see subclause D.2.

RF channels to be tested: M; see subclause 4.7.

1) Connect the BS tester generating the wanted signal, multipath fading simulators and AWGN generators to all BS antenna connectors for diversity reception via a combining network as shown in Annex I.3.2.

8.5.3.4.2 Procedure

1) Adjust the AWGN generator, according to the channel bandwidth.

Table 8.5.3.4.2-1: AWGN power level at the BS input

Channel bandwidth [KHz]

AWGN power level

200

-100.5dBm /180KHz

2) The characteristics of the wanted signal shall be configured according to the corresponding UL reference measurement channel defined in Annex A.

3) The multipath fading emulators shall be configured according to the corresponding channel model defined in Annex B.

4) Adjust the frequency offset of the test signal according to Table 8.5.3.5-1.

5) Adjust the equipment so that the SNR specified in Table 8.5.3.5-1 is achieved at the BS input during the NPRACH preambles.

6) The test signal generator sends a preamble with repetitions and the receiver tries to detect the preamble. This pattern is repeated as illustrated in figure 8.5.3.4.2-1. The preambles are sent with a fixed timing offset of during the test, where is NPRACH cyclic prefix of length as defined in TS36.211 [12]. The following statistics are kept: the number of preambles detected in the idle period and the number of missed preambles.

Figure 8.5.3.4.2-1: NPRACH preamble test pattern

8.5.3.5 Test Requirement

Pfa shall not exceed 0.1% and Pmd shall not exceed 1% for the SNRs in Table 8.5.3.5-1.

Table 8.5.3.5-1: NPRACH missed detection test requirements for FDD

Number of TX antennas

Number of RX antennas

Repetition number

Propagation conditions and

correlation matrix (Annex B)

Frequency offset

SNR[dB]

Preamble format 0

Preamble format 1

Preamble format 2

1

2

8

AWGN

0

-1.8

-1.8

-0.7

EPA1 Low

200 Hz

6.7

6.7

9.6

32

AWGN

0

-6.5

-6.5

-4.8

EPA1 Low

200 Hz

1.1

1.1

2.8

Table 8.5.3.5-2: NPRACH missed detection requirements for TDD

Number of TX antennas

Number of RX antennas

Repetition number

Propagation conditions and correlation matrix (Annex B)

Frequency offset

SNR[dB]

Preamble format 0

Preamble format 1

Preamble format 0-a

Preamble format 1-a

1

2

8

AWGN

0

5.9

2.8

4.3

1.3

EPA1 Low

200 Hz

15.3

10.7

14.3

9.6

32

AWGN

0

1.2

-1.9

-0.4

-3.3

EPA1 Low

200 Hz

10.4

4.9

10.6

3.1

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 G.