N.1 General

37.5443GPPConformance testingRelease 16TSUniversal Terrestrial Radio Access (UTRA) and Evolved UTRA (E-UTRA)User Equipment (UE) Over The Air (OTA) performance

Editor’s notes: Table N.1-1 is based on a similar table in RAN4 TR 37.977. There are a number of inconsistencies (examples are listed below) and errors in the source table that are still remaining in Table N.1-1. They should be fixed once RAN4 fixes the corresponding table in TR 37.977.

– NOTEs 1, 3 & 4 are not relevant to MPAC; the NOTEs should be removed.

– Item 19 is not relevant to MPAC and should be removed.

– Items 9 and 10 seem to be related to SIR that is out of scope of the WI; these may be removed from the table.

1. Individual uncertainty contributions in the TRMS measurements are discussed and evaluated in this Annex. A technique for calculating the total measurement uncertainty is also presented.
2. An important part of a standard measurement procedure is the identification of uncertainty sources and the evaluation of the overall measurement uncertainty. There are various individual uncertainty sources in the measurement procedure that introduce a certain uncertainty contribution to the final measurement result. The approach in this standard test procedure is that the test laboratories are not limited to using some specific instruments and antenna positioners, for example. However, a limit is set for the maximum overall measurement uncertainty.
3. The TRMS measurement procedure can be considered to include two stages. In Stage 1 the actual measurement of the MIMO OTA throughput of the Device Under Test (DUT) is performed. In Stage 2 the calibration of the absolute level of the DUT measurement results is performed.
4. The uncertainty contributions related to TRMS are listed in Tables N.1-1. The uncertainty contributions are analysed in the following paragraphs.
5. The calculation of the uncertainty contribution is based on the ISO Guide to the expression of uncertainty in measurement. Each individual uncertainty is expressed by its Standard Deviation (termed here as ‘standard uncertainty’) and represented by symbol U. The uncertainty contributions can be classified to two categories: Type-A uncertainties, which are statistically determined e.g. by repeated measurements, and Type-B uncertainties, which are derived from existing data e.g. data sheets. Several individual uncertainties are common in Stage 1 and Stage 2 and therefore cancel.
6. The procedure of forming the uncertainty budget in measurement is:
   • 1. 1) Compile lists of individual uncertainty contributions for measurements in both Stage 1 and Stage 2.
7. 2) Determine the standard uncertainty of each contribution by
8. a) Determining the distribution of the uncertainty (Gaussian, U-shaped, rectangular, etc.)
9. b) Determining the maximum value of each uncertainty (unless the distributions is Gaussian)
10. c) Calculating the standard uncertainty by dividing the uncertainty by if the distribution is U-shaped, and by if the distribution is rectangular.
11. 3) Convert the units into decibel, if necessary.
12. 4) Combine all the standard uncertainties by the Root of the Sum of the Squares (RSS) method.
13. 5) Combine the total uncertainties in Stage 1 and Stage 2 also by the RSS method: .

6) Multiply the result by an expansion factor of 1.96 to derive expanded uncertainty at 95% confidence level: 1.96 * .

Table N.1-1: Measurement uncertainty budget for Multiprobe Anechoic method

	Description of uncertainty contribution	Details in	MPAC
#	Stage 1-DUT measurement		Example Value [dB]	Prob Distr	Std Uncertainty [dB]
1	Mismatch of transmitter chain (i.e. between fixed measurement antenna and base station simulator)	TS 34.114, E.1-E.2	0.00	u-shape	0.00
2	Insertion loss of transmitter chain	TS 34.114, E.3-E.5	0.00	rect	0.00
3	Influence of the fixed measurement antenna cable	TS 34.114, E.6	0.00	rect	0.00
4	Uncertainty of the absolute antenna gain of the fixed measurement antenna	TS 34.114, E.7	0.00	rect	0.00
5	Base station simulator: uncertainty of the absolute output level	TS 34.114, E.17 [TS 36.521-1 F.1.3]	1.00	rect	0.58
6	Throughput measurement: output level step resolution	TS 34.114, E.18	0.25	rect	0.14
7	Statistical uncertainty of throughput measurement	TS34.114, E.19	FFS (negligible and partially included in repeatability)
8	Fading channel emulator output uncertainty (if used) – absolute output power – output signal stability – output stability with temperature	N.2	1.5dB 0.5dB 0.4dB	normal (output power) rect (stability)	0.84
9	AWGN flatness within LTE band	TBD (NOTE 4)			FFS
10	Signal-to noise ratio uncertainty, averaged over downlink transmission Bandwidth	TBD (NOTE 4)			FFS
11	Channel model implementation (NOTE 2)	TBD	FFS		FFS
12	Chamber statistical ripple and repeatability	TS 34.114, E.26.A	N/A		0.00
13	Additional power loss in EUT chassis	TS 34.114, E.26.B	N/A		0.00
14	Quality of the quiet zone	TS 34.114, E.10	0.50	std	0.50
15	Measurement Distance – VSWR – Chamber Standing Wave	TS 34.114, E.9	0.00		0.00
16	DUT sensitivity drift	TS 34.114, E.21	0.20	rect	0.12
17	Uncertainty related to the use of the phantoms:				0.00
	a) Uncertainty of dielectric properties and shape of the hand phantom	TR 25.914, A.12.3			0.00
	b) Uncertainty related to the use of laptop ground plane phantom	TR 25.914, A.12.4			0.00
18	Random uncertainty (repeatability)	TS 34.114, E.14	0.20	rect	0.12
19	Uncertainty associated with the stirring method and number of subframes (NOTE 3)		N/A		0.00
	Stage 2-Calibration measurement				0.00
20	Uncertainty of network analyzer – Receiver and Source VNA – Receiver VNA Calibration prior to measurement	TS 34.114, E.15	0.50	rect	0.29
21	Mismatch of transmitter chain	TS 34.114, E.1-E.2	0.20	u-shape	0.14
22	Insertion loss of transmitter chain	TS 34.114, E.3-E.5	0.00		0.00
23	Mismatch in the connection of calibration antenna	TS 34.114, E.1	0.00	rect	0.00
24	Influence of the calibration antenna feed cable	TS 34.114, E.6			0.00
25	Influence of the transmitter antennas/probes cables	TS 34.114, E.6	0.00	rect	0.00
26	Uncertainty of the absolute gain of the transmitter antennas/probes	TS 34.114, E.7	0.00	rect	0.00
27	Uncertainty of the absolute gain/radiation efficiency of the calibration antenna	TS 34.114, E.16	0.50	std	0.50
28	Chamber statistical ripple and repeatability	TS 34.114, E.26.A			0.00
29	Phase Centre Offset (when using horn to calibrate)	TS 34.114, E.9	0.00	rect	0.00
30	Quality of the quiet zone (Range Ref. Antenna)	TS 34.114, E.10	0.50	rect	0.29
	External Amplifiers				0.00
31	Stability	N.3.1	0.30	rect	0.17
32	Linearity	N.3.2	0.10	rect	0.06
33	Noise Figure	N.3.3	0.30	rect	0.17
34	Mismatch	N.3.4	0.00	rect	0.00
35	Gain	N.3.5	0.00	rect	0.00

NOTE 1: 0dB if fading for RTS is done in baseband; same as RC&CE and MPAC if fading is not in baseband

NOTE 2: assumption is that MU set to 0dB with channel model validation pass/fail limits (FFS) that have negligible impact on TP FOM; MU for channel model validation is FFS

NOTE 3: Analysis of the element associated with stirring method and number of subframes is based on existing harmonization test campaign data and can be further augmented by additional measurements. The following combinations of stirring modes and number of subframes have been identified as common use cases with the following standard uncertainties (different combinations require separate validation):

A: stepped stirring mode with 20k SF per stirring state: 0dB

B: stepped stirring mode with 400 SF per stirring state: 0.22dB

C: continuous stirring mode with 20k SF per sample: FFS

D: continuous stirring mode with 400 SF per sample: FFS

Until MU elements for continuous stirring modes have been defined, the test plan shall only consider stepped stirring approach

NOTE 4: As the applicability of SIR to MIMO OTA performance evaluation is FFS, the measurement uncertainty treatment for SIR related items will remain FFS. When the applicability of SIR is confirmed, the measurement uncertainty treatment defined in 3GPP TS 36.521-1 [11] Table F.1.4-1 for line item 8.2.1.3.1 should be considered along with the related test system constraints. Any adjustments to the test system limits or uncertainty definitions necessary for MIMO OTA performance testing should be applied.