ATDI South Pacific Pty Ltd 79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax...

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ATDI South Pacific Pty Ltd 79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected] ATDI South Pacific Pty Ltd 79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected] Digital Broadcasting Network Design and Analysis 2011. 05. 23 ITU-AIBD-ABU Regional workshop 22-23 May 2011 – Hanoi Pascal GELUGNE - Managing Director ATDI South Pacific [email protected]

Transcript of ATDI South Pacific Pty Ltd 79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax...

Page 1: ATDI South Pacific Pty Ltd 79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email south-pacific@atdi.com ATDI.

ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia

+61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Digital BroadcastingNetwork Design and Analysis

2011. 05. 23

ITU-AIBD-ABU Regional workshop

22-23 May 2011 – Hanoi

Pascal GELUGNE - Managing Director ATDI South Pacific

[email protected]

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Cartographic Data Production

AgendaAgenda

Selecting a Digital Broadcasting Technology

Planning the migration: the coverage aspects- Planning standards and requirements - The simulation parameters- The “same” coverage objective

Planning the migration: the spectrum aspects- MFN network planning- SFN network planning- The Digital dividend - Compatibility between services

International coordination- Coverage outside borders- Working with the ITU

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Cartographic Data Production

Selecting a Digital Broadcasting TechnologySelecting a Digital Broadcasting Technology

• What digital system to select ? (DVB-T, DVB-T2, DVB-S, DVB-H, ISDB-T, T-DMB …)

o What is the targeted market ?

Replacement for Analogue

Outdoor or Indoor Rx antennas ?

Mobile users ?

o What are the technologies performances ?

Selection processSelection process

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Cartographic Data Production

Selecting a Digital Broadcasting TechnologySelecting a Digital Broadcasting Technology

Technical investigations: Using the power of a planning tool

Technical investigations: Using the power of a planning tool• ISDB-T vs DVB-T2 at equivalent payload:

o Simulation using ICS telecom, 25m

cartographic data and a

deterministic model

o DVB-T2 has a 30.9% coverage

increase in this example

o At equal coverage it would mean an

economy of 4 times the Tx power

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Cartographic Data Production

Selecting a Digital Broadcasting TechnologySelecting a Digital Broadcasting Technology

Technical investigations: Validating the Tx modesTechnical investigations: Validating the Tx modeso What compression

standard ?

o Set the transmission

standards (Carrier

mode, Guard interval,

modulation, code

rate)

o Set the reception

parameters

(Outdoor/Indoor,

receiving threshold

standard) Source: ETSI TR 101 190

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Cartographic Data Production

AgendaAgenda

Selecting a Digital Broadcasting Technology

Planning the migration: the coverage aspects- Planning standards and requirements - The simulation parameters- The “same” coverage objective

Planning the migration: the spectrum aspects- MFN network planning- SFN network planning- The Digital dividend - Compatibility between services

International coordination- Coverage outside borders- Working with the ITU

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Know your network parameters: general

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Know your network parameters: patterns

The patterns can be easily imported from standard formats (NSMA, Planet©, excel©…).

The azimut, tilt, polarization, XPD can be easily defined.

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Know your network parameters: parameters dedicated to the DVB signal

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

ICS telecom manages cartographic layers that are necessary for the propagation calculation and display.

Digital cartographic data: medium resolution

DTM Imagery Clutter Census data

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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Which propagation model ?Planning purposes: Deterministic methods

If a proper cartography is used (and it is less a problem to find it in many countries today), the simulation will be realistic. The simulation can also be compared to a measurement campaign for validation.

– LOS

– Diffraction (NLOS)

– Subpath/Multipath attenuation (nLOS)

Note that empirical methodologies are also available, but usually dedicated to cellular technologies.

Regulation purposes

These models are based upon propagation curves following very strict rules (frequency range, Rx antenna height…). They are NOT made to be accurate (and cannot be tuned), but can be used to exchange coordination contours whatever the planning tool and the cartographic data used.

– ITU-R P.370

– ITU-R P.1546

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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Which propagation model ?

ITU-R P.1546 for DVB planning ?

– defined for an Rx antenna height of 10m: a height conversion factor used to used

– to be used with effective antenna height that are not sensitive to cartography

– cannot be tuned unless failing the ITU compliancy

– limited in close range environment

The 1546 is perfect for what is made for: coordination. It can be used whatever the tool and the cartography used, and the direct consequence is its lack of accuracy.

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

Simulation parametersSimulation parameters

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Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

The viewer of an analogue signal is ready to “tolerate” a reception that is not perfect. In digital, the switch point between “bad” and “good” is almost immediate.

Grade Decription of the impairment

5 Imperceptible4 Perceptible, but not annoying3 Slightly annoying2 Annoying1 Very annoying

Grade Decription of the impairment

5 Imperceptible4 Perceptible, but not annoying3 Slightly annoying2 Annoying1 Very annoying

The same coverage objectiveThe same coverage objective

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The coverage can be compared with a map of the collection districts, where the number of inhabitants is known.

This analysis can be done:

– in point mode (centroids)

– in area mode linear distributed

– in area mode distributed according to the clutter

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

The same coverage objectiveThe same coverage objective

Ensure that the digital service provides « same coverage » as the analogue service:

Both services must be modelled in the planning tool considering:

– The right frequency for each service

– The right min required FSR for each service

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DTV 60W ERP 54dBµV/m only

Analogue 400W ERP 64dBµV/m only

Reception of both signals

The propagation model takes the suburban/urban attenation into account.

The directivity of the Rx can be taken into account.

DTV - Band V Analogue - Band V

Rural 54 64

Suburban 67 73

Urban 74 77

Median field strengthE(50,50)dBµV/m

Planning the migration: the coverage aspectsPlanning the migration: the coverage aspects

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Cartographic Data Production

AgendaAgenda

Selecting a Digital Broadcasting Technology

Planning the migration: the coverage aspects- Planning standards and requirements - The simulation parameters- The “same” coverage objective

Planning the migration: the spectrum aspects- MFN network planning- SFN network planning- The Digital dividend - Compatibility between services

International coordination- Coverage outside borders- Working with the ITU

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In order to provide coverage, two conditions must be respected:

– Enough signal strength C should be provided

– This signal must be a certain number of dB higher than the noise floor N of the Rx C/N ratio. Interference will generate a raise of the noise floor, and therefore a decrease of the C/N: C/N+I

Digital broadcast can work in different spectrum modes:

– Multiple frequency networks: MFN

– Single frequency networks: SFN

– A mixture of both: several SFNs working in MFN one with each other for instance

Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo Tx1 coverage only

o Flat Earth

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo Tx1 coverage only

o Terrain model

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo Tx1 coverage only

o Terrain model

o Clutter model

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo Tx2 coverage only

o Terrain model

o Clutter model

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo TX1 + Tx2 coverage

o Terrain model

o Clutter model

o Non optimised SFN timings (-100 µs)

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo TX1 + Tx2 coverage

o Terrain model

o Clutter model

o Non optimised SFN timings (0 µs)

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The SFN network planningThe SFN network planningo TX1 + Tx2 coverage

o Terrain model

o Clutter model

o Optimised SFN timings (49 µs)

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Planning the migration: the spectrum aspectsPlanning the migration: the spectrum aspects

The Digital dividendThe Digital dividendATDI re-assigned Belgium DTV spectrum by :

• Calculating the coverage maps of the existing assignments

• Using the C/N+I ratio defined in the ITU Rec 1368 (DVB-T vs DVB-T…) 15dB

• Without using channels 56-69 (112MHz) = Digital Dividend

Constraints for this work:

• All channels had to be

re-assigned!!!

• The foreign

neighboring countries

were not taken into

account.

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The spectrum compatibility is checked by ensuring:

- That the analogue network is not interfered by the introduction of the DVB network

(using C/I DVBAnalogue protection ratios)

- That the DVB network introduced is not interfered by the analogue network

(using C/I AnalogueDVB protection ratios)

Compatibility with existing servicesCompatibility with existing services

Interference calculationInterference calculation

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Compatibility with existing servicesCompatibility with existing services

Impact on existing servicesImpact on existing servicesRadio-planning a compatibility requires the use of detailed protection from a service A into a service B, and from a service B into a service A.

DTV wanted coverage DTV wanted coverage area once adjacent channel DAB transmitter is setup

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia +61 (0)2 9213 2200 Fax +61 (0)2 9213 2299 email [email protected]

Cartographic Data Production

AgendaAgenda

Selecting a Digital Broadcasting Technology

Planning the migration: the coverage aspects- Planning standards and requirements - The simulation parameters- The “same” coverage objective

Planning the migration: the spectrum aspects- MFN network planning- SFN network planning- The Digital dividend - Compatibility between services

International coordination- Coverage outside borders- Working with the ITU

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Cartographic Data Production

International coordinationInternational coordination

Coverage outside bordersCoverage outside borders

Maximum value Station azimuth distance H1 (Wien) H1 (Geneva) Country86 1 268.07 11908 145.04 153.27 LAO87 1 268.95 10902 175.32 180.53 VTN

Calculation of the coverage spill over the borders

- According to international agreements

- Automatic computation of the countries to be

notified

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Cartographic Data Production

International coordinationInternational coordination

Notification and coordination are never so simple

International agreements

Working with the ITUWorking with the ITU

ICAO

IALA Vienna

Wiesbaden

Chester

BT/BCST’61GE’84GE’89GE’06

LF/MF BCGE’75RJ ’81RJ ’88

MaritimeAeronauticalGE’85MGE’85N

Regional agreements:• FACSMAB• …

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ATDI South Pacific Pty Ltd79 Macarthur Street - Ultimo NSW 2007 Australia

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Thank you!Cảm ơn!

ATDI South Pacific

Pascal GELUGNE - Managing Director ATDI South Pacific

[email protected]