challenges during lte rollout and how to tackle them - fhi · challenges during lte rollout – and...

Challenges during LTE rollout – and how to tackle them

Christian Fischer

Product Manager Drive Test Tools

Rohde & Schwarz, Munich, Germany

Oct 2013 | LTE challenges | 2

Rohde & Schwarz – The company group at a glance

l History Established 1933 in Munich, Germany

l Type of enterprise Independent family-owned company

l Global presence In over 70 countries, approx. 60 subsidiaries

Sales office in Nieuwegein, Service in Belgium

l Net revenue Approx. EUR 1.9 billion (FY 12/13, July through June)

l Export share Approx. 90 percent

l Employees 9300 worldwide, with approx. 5500 in Germany

l Success A leading international supplier in all of its fields of business


LTE roll out – Challenges over challenges

800MHz is not 900MHz –

and what about 2600MHz?

There are already plenty of

antennas and cabinets on

the rooftop….

Why do we do all of this?


LTE roll out – why do we do all of this?

l End user behavior is best represented when

measurements are performed with smartphone based

measurement systems

l Main reasons for LTE roll out

l Provide high throughput for data services – for customers

l Achieve more efficient use of spectrum – for operators

l Broadband coverage of rural areas – for regulators

l Availability and throughput of data services are the main customer

satisfaction parameters


QualiPoc LTE measurements

Serving

cell Neighbor

cells Data download

Also available for GSM, WCDMA, WiFi

Navigation


Air Interface logging

Forcing Functions (Technology/Band, preferred UARFCN)

Voice Call testing (Call To Any)

Speech Testing (P.862, SQUAD or P.863 NB and WB)

M->L and M->M, MOC and MTC, DL and UL

Data

Ping, FTP DL/UL, HTTP DL/UL, Capacity DL (multi thread HTTP), Iperf UDP/TCP

HTTP Browsing

Messaging (SMS, MMS, Email)

YouTube Video Streaming

Multi-Mix job (Sequence of Voice and Data)

Multi-RAB job (Simultaneous Voice and Data)

Parallel jobs (Up to 3 jobs independently)

2-2.5G 3G

4G

**

**

**

**

**CSFB or

SVLTE

QualiPoc Test Cases


Finding reasons for low data rates l To find the reasons for low data rates, a radio network

scanner is used

Good coverage, low SINR why?

Areas of low data rates

Low coverage, low SINR

SINR RSRP


Good coverage, but low SINR: missing dominance

Pilot Pollution:

Best server SINR

RSRP

SINR RSRP


Coverage measurements

l Using a mobile radio network scanner provides easy

and fast information about coverage and interference

l No band limitations

l Several technologies

in parallel

l High measurement

speed

l Easy one click

evaluation showing

coverage and pilot

pollution problem

spots


800MHz is not 900MHz l 800 MHz – missing experience in this frequency band

l For some operators 900MHz experience is available since years

l Operators are potentially re-using their existing propagation models

l Expectation that 800 MHz is quite similar to 900 MHz

l BUT - reality is different:

l High danger of interference due to long ranging signals

l Coverage measurements required to calibrate propagation models and to

learn about real coverage – and finally capacity


The larger picture


LTE800 frequency assignment plan

Frequency [MHz]

Channel 60

8

MHz

78

2,0

Potential interference danger in low cost DVB-T receivers -

having bad or no RF input filters

l Example from Germany


The real world

TV Transmitter

sideband emissions


RF Power Scan

l RF Power Scan is a “Spectrum Analyzer light”

functionality inside the mobile radio network scanner

Applications:

l Finding mobile radio networks

l Finding external interferers

l Measuring uplink frequencies

l Spectrum clearance

measurements

Advantages:

l Included in scanner – no

separate box needed

l Spectrum may be recorded in

the background

l Geographical location available

l No band limitations

(80MHz…6GHz)


RF Power Scan

RF Power Scan Spectrum view shows

l All defined sweeps

(all bands, downlink, uplink)

l Selected sweep

(incl. Markers)

l „Waterfall diagram“

Complete Spectrum


… and what about 2600MHz?

l LTE 2600MHz – unknown frequency behavior

l Mainly used as capacity extension on hot spots and

indoors

– Trade fairs, airports, downtown, shopping malls

l Small cells, Het Net, micro cells, WiFi offloading

l In a nutshell: everything new…

l Testing of data rates and handovers with smartphone

based measurement systems

l Coverage and interference tests with scanner

l Tele2 live network

in Stockholm,

Sweden

l FDD2600MHz,

20MHz

l HTTP 140MB DL

transfer


LTE 1800MHz – the compromise?

l LTE 1800MHz has turned out to be more than a compromise

l Frequencies are well known for many operators

l 1800MHz Propagation is beneficial

…however, in many cases refarming is necessary

Source: gsacom.com

Number of commercially launched LTE FDD

networks in Sept 2013


Single RAN integration and refarming

l Single RAN: Integration of several technologies

into one cabinet

l Refarming: Re-use of frequencies for new

technology

l Long term advantages

l reduction of space, equipment, site rental costs, power

l Spectrum used more efficiently

l Fewer suppliers

l Short term disadvantages

l Equipment swap - Service interruption

l Measurements for Quality assurance

l Installation and commissioning with potential errors


Handheld Cable & Antenna Analyzer R&S ZVH Handheld Spectrum Analyzer R&S FSH

Basic: BTS maintenance and trouble shooting

BTS output spectrum

Cable loss, Cable faults,

BTS Output power

Geotagging

BTS Parameter

measurements

Connected to BTS Over-The-Air (OTA)

DL Signal quality

measurements

Interference analysis

Extended: interference hunting and cable and

antenna test

Antenna matching

Antenna isolation

Cable faults

Cable loss

BTS output power

BTS output spectrum

Interference hunting


R&S ZVH and FSH Highlights Measurement Wizard & Report Generator l The wizard guides the user through the measurement sequence.

Written instructions and pictures can be added to each

measurement step

l Back in the office report is ready after a couple of mouse clicks


Conclusion

Still classical installation problems remain

New frequencies need to be managed

High data rates should be achieved

These challenges can be overcome and solved by using

Rohde&Schwarz measurement equipment

New interference scenarios come up


R&S LTE Portfolio for chipset, component, device and base station testing

Signaling Conformance

Radio Network

Analyzers incl. ROMES Drive

Test Tools RF Conformance

R&S®CMW500

including 3GPP

conformance tests

R&S®TS8980

RF Test

System

&

RRM Test

System

R&S®CMW500

Testing of - Protocol Layers

- Operator Scenarios

- E2E Application

- Max. Throughput

- IP4/6

- MIMO

- Handover

Signal Generator / Fading Simulator

Signal Analyzer /

Power Meter

R&S®FSW

R&S®FSV

R&S®SMW200A R&S®SMBV100

One box Mobile Radio Tester for

Calibration, Verification and Functional Test

R&S®CMW500 R&S®FSH/ZVH

TS8980FTA

+ out-of-band and

TV interferer tests

Installation

and

Maintenance

1st TD-LTE RF test

cases validated

by GCF

LTE functionality

since May 2008

TD-LTE,

LTE FDD, GSM,

WCDMA/HSPA(+)

and CDMA2k

in one box!

R&S®NRP

RF Development Protocol Stack Field Conformance

and Production and IOT Testing Testing


R&S LTE information, App. Notes, Videos, etc.

www.rohde-schwarz.com/


Marcel Tersteeg

Account Manager

Broadcast & Telecom operators

ROHDE & SCHWARZ Netherlands

Test and Measurement

Perkinsbaan 1 · 3439 ND · Nieuwegein

P.O. Box 1315 · 3430 BH · Nieuwegein

Tel +31 (0)30 6001722 Mob +31 (0) 6 46324415

email: [email protected]

Internet: www.rohde-schwarz.com

Webshop: www.testenmeetwinkel.nl

Rohde & Schwarz Netherlands Contact details


Thank you

for your attention!

Any questions?

challenges during lte rollout and how to tackle them - fhi · challenges during lte rollout – and...

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