01 RA47051EN16AGLA0 RF Measurement Quantities

RF Measurement Quantities Slide 1

NokiaEDU RF Measurement Quantities LTE Optimization Principles [FL16A] Module 01

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Copyright and confidentiality

The contents of this document are proprietary and confidential property of Nokia. This document is provided subject to confidentiality obligations of the applicable agreement(s). This document is intended for use of Nokia’s customers and collaborators only for the purpose for which this document is submitted by Nokia. No part of this document may be reproduced or made available to the public or to any third party in any form or means without the prior written permission of Nokia. This document is to be used by properly trained professional personnel. Any use of the contents in this document is limited strictly to the use(s) specifically created in the applicable agreement(s) under which the document is submitted. The user of this document may voluntarily provide suggestions, comments or other feedback to Nokia in respect of the contents of this document ("Feedback").

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Such Feedback may be used in Nokia products and related specifications or other documentation. Accordingly, if the user of this document gives Nokia Feedback on the contents of this document, Nokia may freely use, disclose, reproduce, license, distribute and otherwise commercialize the feedback in any Nokia product, technology, service, specification or other documentation. Nokia operates a policy of ongoing development. Nokia reserves the right to make changes and improvements to any of the products and/or services described in this document or withdraw this document at any time without prior notice. The contents of this document are provided "as is". Except as required by applicable law, no warranties of any kind, either express or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose,

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Module Objectives • After completing this module, you will be able to:

• Describe the most relevant quantities: RSRP, RSRQ, RSSI, SINR • Explain the definitions of the measurement quantities and their value ranges

• Give an overview of interdependencies of the different measurement quantities • Revise the meaning of measured values in terms of network performance • Discuss related practical issues and their impact on network analysis

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Course pre requisites • Before taking this course it is expected that the students have attended: or have an equal level of knowledge and experience of the following;

• • • • •

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Confidential

TM5117: LTE Air Interface RA4120: LTE Radio Planning RA4123: LTE Signaling RA4121: LTE Parameters RA4133: LTE Counters and KPI

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Index • RSRP: Reference Signal Received Power

• RSSI: Received Signal Strength Indicator • RSRQ: Reference Signal Received Quality • SINR, CINR, SNR

• Definition and measurement • Mapping RSRP / RSRQ to SINR • MIMO variants of the RF quantities and use cases

• 3GPP defined measurement accuracy for UEs

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Reference Signal from 3-Sector 2x2 MIMO Cells

R1

R0

R0

R1

R1

R1

R0

R1

R0

R1

R0

R0

R1

R0

R1

R1

R0

R1

R0

R0

R1

R0

R1

R1

R0

R1

R0

R0

R1

R0

R1

R1

R0

R1

R0

R0

R1

R0

R1

R1

R1

R0

R0

Slot (0.5 ms)

R1

R0

R0

R0

Cell#3 (PCI 11)

Cell#2 (PCI 10)

Cell#1 (PCI 9)

R1

Slot (0.5 ms)

Slot (0.5 ms)

Subframe

Slot (0.5 ms)

Slot (0.5 ms)

Slot (0.5 ms)

Subframe

Subframe

R0: RS of antenna port 0 R1: RS of antenna port 1

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• RS frequency shift based on PCI modulo-3

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Reference Signal from 3-Sector 2x2 MIMO Cells -RS as seen by UE from cells of a 3-sector FDD site -no RS-RS interference since PCImod3 are different R1 R1 R1 R0 R0 R0 R1 R1 R1 R0 R0 R0

R0 R0 R0 R1 R1 R1 R0 R0 R0 R1 R1 R1

R1 R1 R1 R0 R0 R0 R1 R1 R1 R0 R0 R0

Slot (0.5 ms)

R0 R0 R0 R1 R1 R1 R0 R0 R0 R1 R1 R1

Slot (0.5 ms)

Subframe

Sector 1: red Sector 2: green Sector 3: blue

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R0: RS of antenna port 0 R1: RS of antenna port 1

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• Same-site cells are frame-synchronized in FDD. In TDD all cells are frame-

synchronized.

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Reference Signal from 3-Sector 4x2/4x4 MIMO Cells

R1 R3

R0 R2

R1 R3

R0 R2

R0

R1 R3

R1

R0 R2

R0

R1 R3

R1

R0 R2

Slot (0.5 ms)

Cell#3 (PCI 11)

Cell#2 (PCI 10)

Cell#1 (PCI 9)

R1 R3

R0

R1 R3

R0

R0 R2

R1

R0 R2

R1

R1 R3

R0

R1 R3

R0

R0 R2

R1

R0 R2

R1

R1 R3

R0

R1 R3

R0

R0 R2

R1

R0 R2

R1

R1 R3

R0

R1 R3

R0

R0 R2

R1

R0 R2

R1

R0

R1

R0

R1

Slot (0.5 ms)

Slot (0.5 ms)

Subframe

Slot (0.5 ms)

Slot (0.5 ms)

Slot (0.5 ms)

Subframe

Subframe

R0: RS of antenna R1: RS of antenna R2: RS of antenna R3: RS of antenna

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port 0 port 1 port 2 port 3

© Nokia 2016

• RS frequency shift based on PCI modulo-3

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Reference signals for TM9 For use in SU 4x4 MIMO and Liquid Cell

11 4

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CRS

UL feedback

MCS PMI Rank

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9 10 11 12 13

1 2 3 4 5

CRS DM-RS CSI-RS PDCCH PDSCH

24 24 4 8 108

TM9 4 layers 4x4 MIMO

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CQI PMI Rank

DL feedback

CSI-RS

5

1

DL feedback

TM4 4 layers 4x4 MIMO

CRS

1

0

CQI PMI* Rank

24 8 136

DM-RS

0 1

CRS PDCCH PDSCH

UL feedback

• PDSCH channel estimation based on demodulation reference signals (DM-RS) – ports 7..14 (up to 8 layers) • CQI report based on Channel State Information Reference Signals (CSI-RS) – ports 15..22 • Closed loop precoding based on CSI-RS, reported by PMI • CSI-RS is configured to each Rel10 UE via RRC reconfiguration

MCS Rank

© Nokia 2016

CSI-RS based feedback: • • • • • • •

CSI-RS introduced to give better indication of PDSCH interference, Cell specific RS suffers from inter cell interference from control channels and other Cell specific RS Channel can be estimated between all eNB-UE antenna pairs No limit on how many UEs can use CSI-RS based channel estimate, regardless of CSI-RS periodicity No impact on UE battery consumption Relatively low and configurable periodicity of CSI-RS subframe Also CSI-RS subframe offset is configurable Helps to avoid CSI-RS collisions in low loaded networks

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RSRP - RSRP is the linear average of received power of RS resource elements

- UE measures the rx power of multiple RS REs and takes average of them - Reporting range -44…-140 dBm Definition

• R0: tx antenna 1 R1: tx antenna 2

Reference signal received power (RSRP), is defined as the linear average over the power contributions (in [W]) of the resource elements that carry cell-specific reference signals within the considered measurement frequency bandwidth. For RSRP determination the cell-specific reference signals R0 according TS 36.211 [3] shall be used. If the UE can reliably detect that R1 is available it may use R1 in addition to R0 to determine RSRP. The reference point for the RSRP shall be the antenna connector of the UE.

Applicable for

If receiver diversity is in use by the UE, the reported value shall not be lower than the corresponding RSRP of any of the individual diversity branches. RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, RRC_CONNECTED inter-frequency

Note1: The number of resource elements within the considered measurement frequency bandwidth and within the measurement period that are used by the UE to determine RSRP is left up to the UE implementation with the limitation that corresponding measurement accuracy requirements have to be fulfilled. Note 2: The power per resource element is determined from the energy received during the useful part of the symbol, excluding the CP.

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Definition in 3GPP TS 36.214

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RSRP Mapping - The reporting range of RSRP is defined from -140 dBm to -44 dBm with 1 dB resolution - The mapping of measured quantity is defined in the table below:

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Reported value

Measured quantity value

Unit

RSRP_00

RSRP  -140

dBm

RSRP_01

-140  RSRP < -139

dBm

RSRP_02

-139  RSRP < -138

dBm

…

…

…

RSRP_95

-46  RSRP < -45

dBm

RSRP_96

-45  RSRP < -44

dBm

RSRP_97

-44  RSRP

dBm

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3GPP TS 36.133 V8.9.0 (2010-03)

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RSRP Measurement Using Different Devices •

Comparison of Samsung UE and R&S TMSW / PCTel EX scanners – UE inside car and scanners using the same antenna mounted on car roof RSRP measurement, idle cell and fully loaded cell -65 1

31

61

91

121

151

181

211

241

271

301

331

361

391

RSRP [dBm]

-70

-75

2-3dB difference in measured RSRP

-80

PCTel RSRP R&S RSRP UE RSRP

-85

-90

UE starts downloading

time, seconds

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Samsung UE inside car, R&S and PCTel scanners in the same antenna via power splitter on the car roof. Identical antenna line loss for the scanners.

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RSRP vs CPICH RSCP •

Below a measurement of 2.1GHz CPICH RSCP versus 1.8GHz/20MHz RSRP using a multi-RAT multi-band scanner.

•

Should RSRP be scaled somehow to make it comparable to RSCP?

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PCTEL MX measurement simultaneously at 2.1GHz and 1.8GHz RSRP = RS tx power per subcarrier per tx antenna – path loss + antenna gains CPICH RSCP = CPICH tx power – path loss + antenna gain

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Quiz: RSRP vs CPICH RSCP •

Below a measurement of 2.1GHz CPICH RSCP versus 1.8GHz/20MHz RSRP using a multi-RAT multi-band scanner.

• •

Should RSRP be scaled somehow to make it comparable to RSCP? Which one (WCDMA or LTE) is having higher link loss? Assume:

• • •

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40W Tx power for both systems. 10% CPICH power for WCDMA 20MHz bandwidth for LTE

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40w ¨46dBm 1200 ¨30.8dB 200 ¨23dB 2/7 ¨-5.4dB

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RSSI - RSSI is internal to UE, not reported in uplink to eNB

- RSSI measures all power within the measurement bandwidth • hence it includes thermal noise, interference and serving cell power

R0

R1

R0

R0

R1

R0

R1

R1

R0

R1

R0

R0

R1

R0

R1

OFDM symbol containing R0 17

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Time

R1

Freq

- Measured over those OFDM symbols that contain RS for antenna port R 0

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Relation between RSSI and RSRP - RSSI = wideband power= noise + serving cell power + interference power - Without noise and interference, 100% DL PRB activity:

RSSI=12*N*RSRP Where: – N is number of PRBs across the RSSI is measured and depends on the BW - Based on the above, under 100% PRB utilization and high SNR:

RSRP (dBm)= RSSI (dBm) -10*log (12*N)

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Converting RSSI=12xNxRSRP to logarithmic domain, RSSI (dBm) = 10log(12xN) + RSRP(dBm) RSRP (dBm) = RSSI (dBm) – 10 log(12xN)

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Relation between RSSI and RSRP Field Measurement in Fully Loaded 10MHz Cell RSRP versus RSSI for fully loaded cell, 10MHz system bandwidth (100% of REs active)

-93

-88

-83

-78

-73

-68

-63

-58

-53

-48 -75

RSRP [dBm]

-85

-95

-105

Measurement: slope ~28 dB  agrees with theory (27.8dB)

-115

-125 RSSI [dBm]

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Samsung BT-3710 + XCAL

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Relation of RSSI and RSRP Impact in Cell Load -40 1

60 6

11

16

21

26

31

36

-50

- RSRP is independent of cell load

-60

40

SCell-RSSI(Com) SCell-RSRP(Com)

-70

RSSI increases about 5-6dB

-80

-90

RSRP independent of cell load

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Number of RBs

RB Num(DL) Power, dBm

- RSSI increases about 5dB when PRB activity increases to 100%,10MHz cell

50

20

10

UE starts downloading -100

0 Time, seconds

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RSRQ RSRQ = N x RSRP / RSSI Where: • RSSI is pure wide band power measurement, including serving cell power, interference and thermal noise • N: RSSI measurement bandwidth in PRBs

R0: tx antenna 1 R1: tx antenna 2

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3GPP TS 36.214

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RSRQ Mapping - RSRQ reporting range -3…-19.5dB - (Some devices report values < -20dB)

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Reported value


Unit

RSRQ_00

RSRQ  -19.5

dB

RSRQ_01

-19.5  RSRQ < -19

dB

RSRQ_02

-19  RSRQ < -18.5

dB

…

…

…

RSRQ_32

-4  RSRQ < -3.5

dB

RSRQ_33

-3.5  RSRQ < -3

dB

RSRQ_34

-3  RSRQ

dB

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3GPP TS 36.133 V8.9.0 (2010-03)

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RSRQ Theoretical Values in Idle and Fully Loaded Cell RSRQ = N x RSRP / RSSI, N = measured bandwidth in PRBs • Idle cell: When there is no traffic, and assuming only the reference symbols are

transmitted (there are 2 of them within the same symbol of a resource block) from a single Tx antenna then the RSSI is generated by only the 2 reference symbols so the result becomes: – RSRQ = -3 dB for 1Tx

– RSRQ = -6dB for 2Tx - Fully loaded cell: Cell with 100% PRB utilization If all resource elements are active and are transmitted with equal power then – RSRQ = -10.8 dB for 1Tx – RSRQ = -13 dB for 2Tx

In practice, UEs seem to report RSRQ ~neg11dB for fully loaded cell, assuming no other-cell interference

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RSRQ/SNR/RSRP Measurement, 2Tx cell - Only serving cell on-air, FDD ZTE (QC)

Idle cell RSRQ= neg6dB UE starts downloading

SNR drops but RSRP not

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RSRQ Measurement Using Different Devices •

Comparison of Samsung UE and TMSW / PCTel EX scanners – UE inside car, scanners on car roof using the same antenna RSRQ measurement, idle cell and fully loaded cell 0 -2

1

31

61

91

121

151

181

211

241

271

301

331

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RSRQ [dB]

-4 -6 -8 -10 -12 -14

PCTel RSRQ R&S RSRQ UE RSRQ

-16 -18 -20

UE starts downloading

Measured RSRQ depends on device

time, seconds

NOTE: R&S RSRQ independent of cell load!!

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Samsung UE inside car, R&S and PCTel scanners in the same antenna via power splitter on the car roof. Identical antenna line loss for the scanners.

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SINR / SNR / CINR Definition and Measurement SINR = S / (I+N) • Usually SINR=SNR=CINR unless the receiver is able to separate interference from thermal noise • Example: IRC receiver can separate dominant interferer from noise • The actual measurement definition must be checked for every measurement device

-

which signal the ‘S’ measures?

-

what is the measurement bandwidth?

-

is the measured SNR instantaneous or average value?

-

if the average SNR is measured, what is the number of samples averaged? Typically UEs measure SNR from RS

• • •

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Exact measurement method uncertain, since UE chipset vendors don’t typically reveal technical data Scanners measure SNR from PSS/SSS and/or RS

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SINR Measurement Using Different Devices •

Comparison of Samsung UE and TMSW / PCTel Ex scanners SINR measurement, idle cell and fully loaded cell 80

DL starts, PRB utilization to100%

SINR dBm / throughput Mbps

70

60

PCTel SSS SINR

50

PCTel RS SINR R&S SSS SINR UE SINR

40

DL Throughput 30 20 10 0 1

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61

91

121

151

Secondary Sync Signal SNR much worse than RS SNR 29

181

211

241

271

301

331

361

391

time, seconds

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Sync signal SNR suffers from neigbour sector interference from the same site.

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RS CINR and RSRP Measured by FDD Scanner •Q: What would CINR be if network was fully loaded? Can RS CINR be used

for dominance analysis?

RS CINR

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What would be the CINR at the marker position if all cells were fully loaded?

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Mapping RSRP to SNR Motivation: Sometimes might be useful to be able to map RSRP to SNR

•

•

Assuming only thermal noise, RSRP can be mapped approximately to SNR

•

In practical field conditions, this does not seem to work very well:

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–

Insufficient averaging for fading signal by measurement equipment

–

Tx signal nonlinearities cause EVM that saturates measured SNR to ~25-30dB.

–

Receiver non-idealities, such as carrier frequency offset, Doppler spread, oscillator, phase noise etc also saturate SNR

–

Interference

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EVM= ERROR VECTOR MAGNITUDE

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Mapping RSRP to SNR Samsung XCAL measurement in lab, non-fading channel •Lab measurement in shielded box, UE-reported RSRP versus UE-reported SINR

In 100% loaded cell reported SINR saturates, probably due to subcarrier leakage or other imperfections.

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Mapping RSRP to SNR XCAL field measurement, fading channel • Fading channel measurement, drive test. SINR versus RSRP, measurement

-7

-2

3

8

13

18

23

-75

RSRP [dBm]

-85

Samsung UE measurement values are instantaneous snapshots  high variance due to fading.

-95

-105

-115

-125 SINR [dB]

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Mapping RSRQ to SINR Theory (1/2) -

RSRQ depends on own cell traffic load, but SINR doesn’t depend on own cell load.

•

Used Resource Elements per Resource Block (RE/RB) in serving cell is an input parameter for RSRQ -> SINR mapping

•

Assumption: RSRP doesn’t contain noise power

SINR 

RSRP *12 N Pi  Pn _ 12 N

Pn _ xN  Pn _ RE  xN x  RE / RB _ used N  # RBs RSSI  Pi  RSRP * xN  Pn _ 12 N RSRQ 

N * RSRP RSSI

SINR 

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RSRP *12 N 12  N * RSRP 1  RSRP * xN x RSRQ RSRQ

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Noise + interference power as function of RSSI and RSRP RSSI as function of RSRQ

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Mapping RSRQ to SINR Theory (2/2)

RSRQ vs SINR 30.00

- Equation used:

25.00

12 1 x RSRQ

20.00

2 RE/RB

15.00

SINR (dB)

SINR 

4 RE/RB 6 RE/RB

10.00

8 RE/RB 10 RE/RB

5.00

Where x=RE/RB

12 RE/RB

0.00 -20

-19

-18

-17

-16

-15

-14

-13

-12

-11

-10

-9

-8

-7

-6

-5

-4

-3

-5.00

- 2RE/RB equals to empty cell. Only Reference Signal power is considered from serving cell.

-10.00 RSRQ (dB)

RSRP vs. SNR 40.00

- 12RE/RB equals to fully loaded serving cell. All resource elements are carrying data.

• Currently available measurement UEs and scanners report SINR directly

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30.00 25.00 20.00

SNR (dB)

- In practice, mapping from RSRQ to SINR seems difficult

35.00

15.00 SNR 10.00 5.00 0.00 -135

-130

-125

-120

-115

-110

-105

-100

-95

-90

-85

-80

-75

-70

-5.00 -10.00 -15.00 RSRP (dBm )

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Idle cell: SINR = 12/(2-2)=infinite

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Mapping RSRQ to SINR Lab Measurements

SINR vs. RSRQ

- Lab measurements match well the calculated results

35 30 25

- Measured with Agilent scanner

20

SINR

• RSRP

• RSRQ

15 10 5

• Reference signal SINR

0 -5

- Cable connection between BTS and scanner

-20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

-10

• Attenuator used to reduce signal level

RSRQ Measured - full traffic

• No traffic: only control channels and reference signals

Caculated - no traffic

Calculated - full traffic load

Measured - no traffic

SNR vs. RSRP

• Full traffic load: data send in each RB

40 35 30 25

SNR

20 Measured-full traffic

15

Calculated

10

Measured - no traffic

5 0 -140 -135 -130 -125 -120 -115 -110 -105 -100 -5

-95

-90

-85

-80

-10 -15 RSRP

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Terminals do not report SINR but only RSRQ and RSRP. Note: Validity of formula have been proven in lab under above conditions and with only one cell on air ( i.e. no other cell interference). Measurements from the field will differ as exact load can not be set

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Mapping RSRQ to SINR Field Measurement RSRQSINR mapping have high variance in field conditions.

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Terminals do not report SINR to eNB, only RSRQ and RSRP.

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• RSSI: Received Signal Strength Indicator • RSRQ: Reference Signal Received Quality • SINR, CINR, SNR • Definition and measurement

• Mapping RSRP / RSRQ to SINR • MIMO variants of the RF quantities and use cases • 3GPP defined measurement accuracy for UEs

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MIMO Variants - Terminals and scanners may report RSRP, RSSI, RSRQ, SINR per receiver antenna - Example: RSRP

• RSRP0 measured at rx. antenna 0 • RSRP1 measured at rx. antenna 1 - Measurement capabilities should be checked case-by-case - Some devices measure even more MIMO quantities • Altair chipset measures four SINR values for a 2Tx BTS, one value per Tx-Rx pair

• Some scanners and the old LG chipset measures antenna correlation coefficient - Question: How can these multi-antenna measurements be used in practical field testing?

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Use cases for multi-antenna RF quantities - MIMO throughput is degraded by: • Too large power imbalance between receiver branches

• Too large power imbalance between Tx branches • High Tx/Rx antenna correlation - In practice, only power imbalance can be measured by commercial devices

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Rx Antenna Power Imbalance Field Measurement - Note RSSI power imbalance between receive antenna branches • This should be eliminated, if possible 02/18/2010 14:13:33.716

-45 02/18/2010 14:15:16.143 -50

02/18/2010 14:16:58.647

02/18/2010 14:18:40.153

02/18/2010 14:20:22.159

02/18/2010 14:22:03.167

-55

-60

RSSI [dBm]

-65 Data Average of SCell-RSSI(Com) Average of RSSI(Ant0) Average of RSSI(Ant1)

-70

-75

-80

-85

-90

-95 time Time

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Rx Antenna Power Imbalance: Impact On Rank Field Measurement - Too large antenna power imbalance can reduce channel rank  tx falls to single stream even at high SNR -65

RSSI0 RSSI1

-70 -75 Rx power imbalance

-80 -85 -90

50

100

150

200

250

300

350

400

450

500

550

seconds Rank fluctuation at high RSSI (SNR)

Rx power imbalance dB

10 5

Rank indicator, {0,1}

0 -5

50

100

150

200

250

300

350

400

450

500

550

seconds 43

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If antenna power imbalance is large, second branch is effectively removed. In field tests, it’s difficult to tell whether rank reduction is caused by power imbalance or channel correlation, since often these happen simultaneously (e.g. line-of-sight).

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Channel Correlation - High channel correlation degrades multi-stream throughput performance – Even high SNR won’t improve throughput if channel correlation is too high

- Typical problem case: Two vertical antennas on car roof  SNR is excellent but MIMO throughput is bad – Solution: use cross-polarized antennas, or take antennas inside car!

- Problem: Channel correlation is not usually reported by DT tools or scanners

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Channel Correlation, Drive Test Example - The same dt route driven twice, 2.6GHz@10MHz, Huawei E398, tm3 • vertical: two vertical scanner antennas mounted on car roof, mean tput = 29Mbps

• x-pol: custom-made cross-polarized omni antenna on car roof, mean tput = 33Mbps x-pol versus two vertical

1 0.9 0.8

0.6

CDF

x-pol vertical

x-pol has better peak tput

0.7

0.5 0.4 0.3

Vertical has better tput in bad RF

0.2 0.1 0

45

0

10

20

30 40 MAC DL tput, Mbps

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In the test, x-pol had 5dB worse total gain due to attenuation in the RF feeder network. Regardless, xpol gives higher peak tput.

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Impact of Channel Correlation on MIMO Tput Measurement Example, SINR=25dB - SINR=25dB, constant over the measurement

- High spatial correlation causes rank-1 transmission even at very high SNR!! (second stream tput goes to almost zero) PHY tput for substreams, EPA 3km/h, 2.6GHz, 3GPP low, medium, high correlation 90 stream 1 stream 2 stream 1 + stream 2

80 70

PHY tput [Mbits/sec]

60

low spatial correlation

High spatial correlation

50 40 30 20

medium spatial correlation

10 0 50

46

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250

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3GPP high, medium, low, medium, high. SNR=25dB (set in fading simulator)

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Impact of UE Orientation Measurement in Excellent RF PHY tput [Mbps], CINR [dB]

100

80

60

PHY DL Throughput [Mbps] CINR 0 [dB] CINR 1 [dB]

40

20

1 19 37 55 73 91 109 127 145 163 181 199 217 235 253 271 289 307 325 343 361 379 397 415 433 451 469 487 505 523 541 559 577 595 613 631 649 667

0

UE orientation changes

Time

1 19 37 55 73 91 109 127 145 163 181 199 217 235 253 271 289 307 325 343 361 379 397 415 433 451 469 487 505 523 541 559 577 595 613 631 649 667

-55

-60

RSRP [dBm]

Main message 1: MIMO throughput is very sensitive to UE orientation!

-65

-70

-75

-80

-85

47

Main message 2: Eliminating power imbalance or channel correlation alone is not sufficient for good MIMO throughput. Both should be eliminated! In practice, this is a trial and error process in stationary measurements.

Antenna0 RSRP [dBm] Antenna1 RSRP [dBm]

Time RA47051EN16AGLA0

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MIMO throughput impacted by SINR, power imbalance and channel correlation. These almost impossible to control in field conditions.

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LTE Tx antenna imbalance impact on throughput. Also imbalance in Tx branch power impacts on MIMO performance. - Improper antenna connector or feeder installation. - Asymmetric indoor installation.

Indoor testing results: • 6dB difference -> average 5.51 Mb/s (11%) lower throughput. • 10dB difference -> average 9.94 Mb/s (20%) lower throughput. • 13dB difference -> average 14.33 Mb/s (29%) lower throughput.

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Measurement Accuracy Requirement: RSRP 3GPP TS 36.133 (simplified) • RSRP absolute accuracy

under normal conditions

• ± 6dB intra-frequency and inter-frequency

• Needed for setting random access pre-amble tx power and triggering coverage-based handover (A5) - RSRP relative accuracy between two cells under normal conditions • ± 2dB intra-frequency • ± 6dB inter-frequency

• For triggering better cell handover (A3)

• RSRP reporting range in signaling (handovers):

50

Reported value


Unit

RSRP_00

RSRP  -140

dBm

RSRP_01

-140  RSRP < -139

dBm

RSRP_02

-139  RSRP < -138

dBm

…

…

…

RSRP_95

-46  RSRP < -45

dBm

RSRP_96

-45  RSRP < -44

dBm

RSRP_97

-44  RSRP

dBm

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Measurement Accuracy Requirement: RSRQ 3GPP TS 36.133 (simplified) - RSRQ absolute accuracy under normal conditions • ± 2.5dB intra-frequency and inter-frequency

- RSRQ relative accuracy between two cells under normal conditions • ± 3dB inter-frequency (intra-frequency not defined) - RSRQ reporting range in RRC signaling (handovers) Reported value

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Unit

RSRQ_00

RSRQ  -19.5

dB

RSRQ_01

-19.5  RSRQ < -19

dB

RSRQ_02

-19  RSRQ < -18.5

dB

…

…

…

RSRQ_32

-4  RSRQ < -3.5

dB

RSRQ_33

-3.5  RSRQ < -3

dB

RSRQ_34

-3  RSRQ

dB

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NokiaEDU

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01 RA47051EN16AGLA0 RF Measurement Quantities

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