Macro Network Enhancements - Dubai

Enabling smart Macro Network Enhancements with Mobile Network Testing

Peter Busch, Arnd Sibila Rohde & Schwarz Mobile Network Testing

Contents ı

Drivers and measures for capacity increase

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How to measure capacity in a Mobile Network?

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Macro cell site grid optimizatio optimization n Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

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Macro Network Densification

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Conclusion

Contents ı


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Macro cell site grid optimizatio optimization n Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

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ı

Conclusion

Mobile Data Traffic Growth: it is happening! Ref: Ericsson Mobility Report (Q2 2016)

Peta Bytes per month

Cisco VNI Mobile

Source: Cisco VNI Mobile, 2016 ı

ı

Mobile data data traffic gro wt h is not a myth, it is rea real! l! Operators Ope rators have to invest to pr ovide higher capacity (Where? How much? When?)

2014

Network Capacity: Where to invest? Factors of the 1000x data challenge (2010 – (2010 – 2020) 10x Performance

10x Spectrum

10x Base Statio Stations ns

1000x Capacity

Main Driver

The Ne Netw twork ork KP KPII

In practice

Continuous need for higher capacity

More spectral efficiency per unit area (bps/Hz/area)

Higher real-world capacity per unit area (in loaded network)

► Optimizing the existing (macro cell) site grid is (often) more cost-efficient compared to new sites Investment in HetNet architectures architectures is driven by the Business Business Case ► Investment

Capacity expansion at macro cell site grid? 10x Perform ance Technology: Drive the spectral efficiency to the theoretical limits Technology evolution: HSPA+, LTE, LTE-A, initial 4.5G or 5G, etc.

Interference mitigation features: ICIC, IRC, eICIC, etc.

Antenna: Optimization of macro site antenna deployments Antenna Tilt optimization (interference minimization)

MIMO, Antenna Arrays, Active Antenna Systems (AAS)

Higher sectorization (3  6 sectors, cell splitting gain)

► Optimizing the existing (macro cell) site grid is (often) more costefficient compared to new sites (e)ICIC: (enhanced) Inter-cell Interference Coordination

IRC: Interference Rejection Combining

Contents ı


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How to measur e capacity in a Mobi le Network?

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Macro cell site grid optimization Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

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Conclusion

Key challenges for MNOs during capacity enhancements/upgrades Execution: Macro cell enhancements

Preparation

ı

ı

ı

OSS provides triggers for capacity enhancements (network view). MNO True network performance Success perceived by end users before capacity enhancement? Business case: Measurements to get evidence about gains in addition to simulations (e.g. where 4x4 MIMO is beneficial)?

Networ k Perfor mance

ı

Are there means to support

Verification

ı

True network performance

execution of capacity

perceived by end users after

enhancements (e.g. trouble

capacity enhancement?

shooting)?

should be measured in a reliable way from users’ perspective OSS: Operations Support Systems

Network structure vs. Test Case structure (scope of tests?) Access Network

UE

Core Network

App Servers

MNO core services and own apps Pure MNO Network SW client / app

SW client / app

3rd party apps (OTT)

Ping, HTTP/FTP, Capacity Test, Iperf Netw ork Perfor mance Test for testing the pure MNO network

Under MNO contro l , e.g. VoLTE, CS-Voice, SMS, MMS, EVS, …

Out of MNO cont rol, e.g. Skype, Youtube, Spotify, Facebook, WhatsApp, Ookla , …

Network Performance Test *) – definition and typical result Data request

Capacity peak

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Continuous TCP load floor

User data rate

All times configurable

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Capacity peaks = one or more parallel TCP connections

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DL or UL or alternating

Time Example of user experienced data rate depending on

TCP throughput ramp-up Average peak throughput

Slight dip below constant data rate Outage

Time

ı

Position in cell

ı

Network load

ı

Technology

ı

Channel (fading,…)

ı

…

*) Patent Pending

Network Performance Test – Result example LTE-A Exp: LTE-Advanced Network: ı

NPT Capacity peaks even triggered

the BS to switch on the 2 nd component carrier (LTE CA – yellow area) – see t1 and t2 ı

Shortly after the capacity peak the 2nd carrier has been switched off again – see t3

ı

TCP load floor at 1Mbps shows 100% full connectivity

ı

Results also available on map



True view of your network

Network Performance Test (NPT) – main customer benefits NPT key use case Emulating future innovative applications

Network capacity testing

Customer benefits

Target customer group

Faster time-to-market for innovative apps (own or OTT)

Marketing / Benchmarking

Reduced risk for own network (modeling “the unknown future”)

Planning / Operations / Optimization / Engineering

Reduced co sts:  shorter measurement times (own network)  less invest in test SIMs for benchmarking competitors’ networks

Optimization / Operations / Benchmarking

Higher efficiency:  true view of own network (eliminates external impacts, e.g. 3 rd party servers)  reduced network load during test

Operations / Optimization / Engineering

Contents ı


ı


ı

Macro cell site grid optimi zation Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

ı


ı

Conclusion

Antenna Tilt Optimization What is the impact of antenna tilt misalignment? Example antenna: 21 dBi antenna gain, 4 degrees VBW (vertical beamwidth),

Antenna height H: 20m

Antenna Downtilt: 4 degrees Inner Cell Radius:

190m

Outer Cell Radius: 573m

coverage area quadrupled due to

Downtilt misaligned by only 1 degree: Inner Cell Radius:

229m

Radius doubled and

Outer Cell Radius: 1145m

tilt misalignment by only 1 degree



Antenna tilt misalignment results in too big / too small coverage (high interference or coverage holes).



Antenna tilt optimization ensures proper handover areas and minimize interference = optimize capacity

Impact of too big coverage (Best Server RSRP and RS-SINR) – Real data

RSRP = coverage

SINR = throughput

In areas where coverage of different cells overlap a lot • power levels are high (RSRP in LTE)

Good coverage, low SINR  why?

Low coverage, low SINR

• but interference levels are also high (RS-SINR low) • cell performance may be low Pilot

Areas of low data rates

pollution!

RSRP: Reference Signal Receive Power RS-SINR: Reference Signal - Signal to Interference and Noise Ratio

Trouble shooting: missing dominance, pilot pollution ROMES4 SW platform

RSRP

Network scanners: TSMA TSME

Best server SINR

TSMW

Several BS with a similar Receive Power (RSRP) at the UE 

missing dominance, pilot pollution!

Scanner provides the root cause (measures are obvious – azimuth / tilt optimization) Scanner helps validating network planning models / simulations

Non-intrusive analysis of LTE DL resource allocation 15.5% RB usage; 6.5Mbps due to low MCS of 18

8.8% RB usage; 5.2Mbps due to higher MCS of 25



Configurable observation interval



Efficiency of RB usage (low MCS)? 



RB usage [%]

Average MCS Sched. TP [kbps]

Network design issue (low efficiency)?

Efficiency of competitors‘ networks?

Average number of transport blocks (MIMO usage)

Contents ı


ı


ı

Macro cell site grid optimi zation Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

ı


ı

Conclusion

LTE / LTE-Advanced: Carrier Aggregation Intra-band contiguous Frequency band A

Component Carrier (CC)

Frequency band B

Intra-band non-contiguous

Frequency band A

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Aggregation of 2 or more LTE carriers in DL (or UL) for 1 user (UE)

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Focus is on increasing data rate per user

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Not a capacity enhancement feature per se (apart from bundle gain)

ı

The real capacity enhancement is the investment of more spectrum

Frequency band B

Inter-band Frequency band A

Carrier Aggregation:

Frequency band B

Network Performance Test measures the user perceived throughput in a CA network, too.

Higher order MIMO approach: e.g. 4x4 MIMO 4x4 MIMO: 4 streams

• • • • • •

4 Tx antennas @BS + 4 Rx antennas @UE 4 different signals (streams) sent via 4 BS antennas to 1 user ( UE) using the same resource blocks on air interface In theory: double DL data rate per resource block compared to 2x2 MIMO  Increase cell capacity Uncorrelated paths (multipath richness) and high SINR needed Operators start planning their networks for 4 antennas @BS New UEs needed (4RX complex)

8x8 MIMO: 8 ant.@BS + 8 ant.@UE - more a theoretical case for lab Same air interface resources are used for up to 4 different streams

throu ghput gain !

Why 4x4 MIMO suitability can be different from 2x2 MIMO? BS antenna realization options 2x2 MIMO: Today

BS antenna (1 sector)

State of the art for BS and UE!

4x4 MIMO: Future

≥10λ

4 uncorrelated paths needed for 4 streams

BS antennas (1 sector)

10λ = 3,8m for 800MHz or 1,7m for 1800MHz

But gain is compromised!

Strong impact on BS! 4x4 MIMO feasibility mainly depends on topology / environment (multipath richness)! UE: 4 RX antennas in smartphone form factor not solved yet!

Theoretical concept behind 4x4 MIMO (radio channel) 4x4 MIMO 0

BS Tx

1

0 1

2

2

3

3

 r 0   h00  r   h  1    10  r 2   h20  r   h  3   30

UE Rx

CN ( H )

h02

h11

h12

h21

h22

h31

h32

  0  s0   n0        h13 s1 n1         U  0 h23   s2   n2  0      0 h33   s3   n3   h03 

Channel Matrix H

0 

1

0 0

0   s0   n0       0 V *  s1    n1  0  s 2   n2 

0 0 

2

0



 

3

s  n   3   3 

after „singular -value-decomposition“ of H *

The columns of U are the eigenvectors of H  H The columns of V are the eigenvectors of H *  H H* is the conjugate transpose of complex matrix H.

Rank: number of σi ≠ 0 Condition number:

h01





max

1



number of possible MIMO streams



how suited is the channel for MIMO?



min

If all σi equal CN = 1 (= 0dB) perfect MIMO channel (receiver can solve the linear equation). if CN > 15…20dB bad MIMO channel (receiver cannot easily solve the equation - higher SINR needed) For m ore details please see: https://cdn.rohde-schwarz.com/pws/dl_downloads/dl_application/application_notes/1sp18/1SP18_10e.pdf

Business Decision for 4x4 MIMO – how T&M can help? Cost of 4x4 MIMO:

Benefit of 4x4 MIMO:

Investment? ı 3rd and 4th TX radio chain: ı PAs, filters, RF units ı Baseband capacity, … ı Mast implications: ı Additional antennas ı Additional cables (RF, jumper, fiber) ı Potential construction changes Subsidies for new devices?

Sufficient capacity gain? ı Rank of channel matrix ≥ 3? ı Condition Number sufficiently low (< 15-20dB)? ı SINR sufficiently high? ı Throughput estimated to be sufficiently higher?  Can all this be measured before mass deployment? Yes!

Business Decision Define the region where 4x4 MIMO is beneficial

Test & Measurement to evaluate MIMO feasibility Best T&M Solution for testing MIMO is using unmodified smartphones  available for 2x2MIMO 2x2 MIMO: e m i T 50 Resource Blocks @ 10 MHz

LTE Scanners are able to 1 TSMW 2 TSME ı measure the channel matrix components ı calculate the Rank and Condition Number Low values for CN (green)  well conditioned = suitable for 2x2 MIMO

4x4 MIMO: a) Solution with scanner available:

ROMES + 4 TSME

+ 4 RX antenna

Test & Measurement to evaluate MIMO feasibility Best T&M Solution for testing MIMO is using unmodified smartphones  available for 2x2MIMO 2x2 MIMO: e m i T 50 Resource Blocks @ 10 MHz

LTE Scanners are able to 1 TSMW 2 TSME ı measure the channel matrix components ı calculate the Rank and Condition Number Low values for CN (green)  well conditioned = suitable for 2x2 MIMO

4x4 MIMO: a) Solution with scanner available:

ROMES + 4 TSME

+ 4 RX antenna

Real data from a 2x2 MIMO Test in a world leading operator’s network R&S Solution: s b o j / s e l p m a s f o e g a %

Vehicle Roof Box, QualiPoc Android Modified phones (external antennas)

SW on smartphone in TCM

Unmodified phones (internal antennas)

(Test Device Containment Module)

You have to measure corr ectly %age of resource blocks using MIMO (2 streams) per sample / job

(closest to real wo rld)!

Operator statements: ı ı

Vehicle Roof Box with unmodified phones is the right approach for E2E assessment more future-proof for smartphone antenna evolution with many more integrated antennas

How to test 4x4 MIMO feasibility?  Customer trial setup MNO + Infrastructur e Supplier:

Drive and w alk tests w ith Netw ork

Upgrade a few tr ial BS si tes to 4 Tx

Scanners:

2x2MIMO (crosspol.) per sector

ROMES4

4x4MIMO per sector

2 times 2x2 cross-pol. with 10λ distance



+ 4 TSME + 4RX antenna Antenna prototype as shown on MWC2016

RF tests of interest: ı Multipath propagation / richness Rank, Condition Number ı ı SINR ı Throughput estimation will come soon

Trial provides insights in 4x4 MIMO capacity gain and defines 4x4 MIMO region

Gain Potential of 4Tx@BS and 4Rx@UE antenna configuration SU MIMO: (cell center)

SU MIMO: (cell edge)

1 users 4x4 MIMO

1 users (2 x 2x1)

SU MIMO: (cell edge) MU MIMO: 2 users 2x2 MIMO 1 user 4x1 2 times 2 streams

4 streams

2 streams (Tx diversity)

1 stream (RX diversity)

For MIMO uncorrelated paths (multipath richness) and high SINR needed Big gain potential by 4Tx@BS and 4Rx@UE throu ghout the wh ole network : 4x4MIMO gain is jus t one part of i t (in good radio c onditi ons)

Benefits of High Order MIMO (e.g. 4x4) t u p h g u o r h T

Source: Vodafone / Ericsson Coverage

4x4 MIMO (device status)

Global mobile Suppliers Association gsacom.com, Status Apr. 4, 2017

Vendor

Model

Support

Samsung Sony Mobile Samsung Samsung Samsung

SM-G930/935T Galaxy S7 and S7 Edge (T Mobile US)

Cat 9, MIMO 4x4, 256QAM (downlink), VoLTE

Xperia XZ 601SO (Softbank Japan)


SM-G950/955A Galaxy S8 + S8 Plus (AT&T US)


SM-G950P Galaxy S8 (Sprint US)


SM-G950/955T Galaxy S8 + S8 Plus (T-Mobile US)


Samsung

SM-G950/955U,W Galaxy S8 + S8 Plus (Unlocked US, Rogers Cat 16, MIMO 4x4, 256QAM (downlink), VoLTE Canada)

Samsung

SM-G950/955V Galaxy S8 + S8 Plus (Verizon US)


Huawei

P10 Plus Standard Edition VKY-L29 (International?)


Huawei

P10 Plus Premium Edition VKY-AL00 (China)


More to come soon  Ecosystem is improving Chipset (data processing) is pre-condition (Qualcomm 820/835, HiSilicon Kirin 9), but antenna design is limiting factor (4Rx)

4x4 MIMO – gain potential Samsung Galaxy S7edge (T-Mobile US variant) tested with CMWflexx in TS7124 Shielded box: High peak throughput by 4x4 MIMO (4 signals transmitted and received in good conditions) Superior throughput at cell edge: ı

BS 4 Tx antennas: Transmit diversity (2 signals transmitted by 2 antennas each)

ı

RX diversity in UE (2 signals received by 2 antennas each)

Source: cellularinsights.com, Oct.2016

The higher the number of 4x4 capable devices, the stronger the gain in network capacity

Signals Research Group measured a 55% speed boost on live T-Mobile US network using Samsung 4×4 MIMO devices (18.1.2017)

4x4 MIMO (device status) Samsung Galaxy S7 and S7 Edge (T-Mobile US variant, special FW) support 4x4 MIMO in band 2 and 4 (not in other bands 5, 7, 12, 41) Bd 12 (700 lower)

Bd 5 (850)

Bd 2 (1900)

Bd 4 (AWS)

Bd 7 (2600)

DL

729 - 746

869 - 894

1930 - 1990

2100 - 2155

2620 - 2690

UL

699 - 716

824 - 849

1850 - 1910

1710 - 1755

2500 - 2570

Signals Research Group measured a 55% speed boost on live T-Mobile US network using Samsung S74x4 compared to S7-2x2 (18.1.2017)  average data rates of 35.3 Mbps (4x4 MIMO) vs. 22.8 Mbps (2x2 MIMO) tested with Accuver Americas XCAL-M drive test solution Sony Xperia X Performance (customized) supports 4x4 MIMO in bd 1 (2100MHz), bd 3 (1800 MHz), band 7 (2600 MHz) measured in VDF Germany test network (connected to ROMES) • Sony Xperia X Performance integrated in QualiPoc (since Sept. 2016) 

Still initial phase for UE ecosystem for 4x4 MIMO: more to come

4x4 MIMO summary ı

4x4 MIMO is an LTE capacity enhancement feature

ı

4x4 MIMO is substantially different from 2x2 MIMO (4x4 feasibility and gains are highly depending on environment)

ı

Commercial 4x4 MIMO smartphone-type UEs are just starting

ı

4x4 MIMO has implications at BS sites

ı

Channel matrix Rank (how many streams) and Condition Number (MIMO suitability of channel) and SINR are crucial values for 4x4 MIMO feasibility

ı

Main business question is not “IF?” but “WHERE?”  region

ı

R&S supports 4x4 MIMO measurements NOW with ROMES + 4 TSME

ı

4Tx at BS side and 4Rx at UE side  big capacity gain potential (4x4 MIMO is just one part of the gain)

Contents ı


ı


ı

Macro cell site grid optimi zation Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı ı Higher order sector ization: 3

ı


ı

Conclusion

6

Higher sectorization (3  6 sectors) 3-sector site

6-sector site

Concept: Increase # of cells per area 

Higher reuse of air interface resources  “Cell splitting gain”  Higher capacity (< factor of 2)  Handover areas relatively bigger than for 3-sectors sites sectorization

Main target Handover areas • as big as necessary for handover AND • as small as possible (to limit interference)

Remember “Tilt Optimization”: TSME TSMA TSMW Network Scanners and ROMES SW for optimization and trouble shooting

ROMES

Contents ı


ı


ı

Macro cell site grid optimization Antenna tilt optimization ı Carrier aggregation ı 4x4 MIMO ı Higher order sectorization: 3 6 ı

ı

Macro Netw ork Densif ication

ı

Conclusion

Macro Network Deployment Workflow (also suitable for indoor / small cell) Service Monitoring

Deployment phase:

Plan & Design

Installation / Acceptance

Trouble Shooting

PIMPro QP Android

TSMA

or

ZVH FSH QP TSMA

QP Probe Smart Monitor

PIMPro

or

FIP

QP Android ROMES4 ZVH FSH PR100 Freerider III TSME

Optimization QP Android

or

ROMES4

Deployment complexity and business impact decide the T&M usage Main target: Verify capacity improvement after deployment vs. situation before

Conclusion ı

Network capacity enhancements have to be done continuously / cyclic process

ı

R&S Network Performance Test measures true performance before/after capacity enhancement from end user perspective

ı

Only unmodified smartphones provide accurate measurements!

ı

R&S Scanners / ROMES provide root cause for low throughput (pilot pollution, etc.)

ı

4x4 MIMO adds substantial complexity to BS and UE

ı

R&S 4x4 MIMO T&M solution helps defining the beneficial 4x4 MIMO region (to limit investment to the right area - main question is not “IF?” but “WHERE?” ) Rohde & Schw arz Mobile Network Testing s upports the custo mers to deliver better services, higher quality and to g et more value out o f their netwo rks!

Thank you

– Questions?

www.swissqual.com www.rohde-schwarz.com/mobile-network-testing

Backup

Site Survey (and calibration of planning tools) ı

Freerider III and TSME scanner for Quality of Experience / Benchmarking and coverage / SNR measurements 

or

Portable, smartphone-based multi-channel solution for extended walk and drive test-based quality of experience benchmarking campaigns and optimization (up to 6 QualiPoc Android smartphones)  Ruggedized, powerful, and future-proof hardware (efficient, uninterrupted, and reliable data collection)  QualiPoc controlling master tablet to configure and operate the system and to monitor the measurement and KPIs in real-time  R&S®TSME RF Scanner to simultaneously and seamlessly measure up to 8 technologies in wireless communication bands from 350 MHz to 4.4 GHz (incl. Automatic Channel Detection, LTE DL Allocation Analysis, etc.) 

Or QualiPoc Android with R&S®TSMA Scanner (same feature set as TSME) for easier deployments

R&S®ZVH Handheld Cable & Antenna Analyzer The fastest cable and antenna analyzer on the market ı

Frequency range 100 kHz to 3.6 GHz or 8 GHz

ı

Cable and antenna installation measurements

ı

Factory calibration eliminates the need of calibration in the field

ı

Measurement WIZARD avoids measurements faults

ı

Report generator c reates custo mized reports easily

R&S®FSH The multi-feature handheld platform ı

ı ı ı ı ı ı ı

Spectrum & quality measurements of LTE (FDD / TDD), WCDMA, GSM, CDMA2000, 1xEV-DO and TD-SCDMA downlink signals OTA Tester (also for 2x2 and 4x4 MIMO) Interference Analyzer Vector Network analyzer Cable and antenna tester Power meter Geotagging & indoor mapping EMC measurement receiver and channel scanner

R&S®ROMES4 - The Flexible Expert Optimization Software ROMES4 SW for network engineering, analysis, optimization and troubleshooting ROMES4 supports advanced RF as well as performance measurements including data and speech quality analysis.

R&S®ROMES with R&S®TSME and testmobile

Runs on standard PC with Windows OS

R&S®ROMES running on R&S®TSMA

or

Runs directly on portable autonomous scanner R&S®TSMA with control via tablet

Portable Receiver R&S®PR100/EM100 ı

Frequency Range 9 kHz to 7.5 GHz

ı

10 MHz IF-bandwidth = ‚real time bandwidth‘

ı

Integrated preselection

ı

Signal recording internally in device and to SD memory card

ı

RF and IF spectrum + waterfall display mode

ı

Light weight / 3.5 kg (PR100)

Portable Antenna R&S®HE300: 9 kHz to 20 MHz

20 MHz to 200 MHz

200 MHz to 500 MHz

500 MHz to 7.5 GHz

PIMPro Tower The lightest and most powerful PIM analyzer ı ı

ı ı ı ı

Bands: 700, 800, 850, 900,1800,1900, 2100, 2600 One-port measurements: Passive intermodulation ı ı Distance to PIM ı Distance to fault Return loss ı Up to 2 x 40 W output power on battery operation mode Lightest unit on the market (2600 model < 10 kg) Easy to operate (smart-phone feel) Easy and quick reporting (HTML and PDF)

Macro Network Enhancements - Dubai

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