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What is Digital Audio

Broadcasting?

FM DAB?

Benefits of using DAB

History of DAB

The DAB system in HK

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What is DAB?

Analog audio

signal

>

Data

SignalProcessor

A/D

Converter

Single Frequency

Network

The quick brown

fox jumps right

over the lazy dog

tail

Digital Audio Signal

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What is DAB?

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FM Vs DAB

FM DAB

Sound QualityLong Play ing

Record

Near CD

MobileReception

Slight ly

Interfered

Interferencefree

Network

Frequency

Mult i - f requenci

es

Single

FrequencyImageBroadcasting

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FM Vs DAB

FM DAB

Receiver Cost

Less Than

Hund red $

Around

$1200Real TimeBroadcasting ?

Yes< 1 second

delay

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Benefits of using DAB

No tuning anymore Radio 1 : 92.6 ~ 94.4MHz

Radio 2 : 94.8 ~ 96.9MHz

Radio 4 : 97.6 ~ 98.9MHz

88 108

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Benefits of using DAB

Interference free mobile reception

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Multiplex

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Dynamic Range Control

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Benefits of using DAB

Multi-

media

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Multi-

media

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History of DAB

Digitalization was proposed by the

British Broadcasting Corporation. TheNICAMsystem is one of their products.

80 88 90 94 97 98 99

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History of DAB

The first generation of the DAB

system was demonstrated inSwitzerland.

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History of DAB

USA did not adopt this development.

They develop another digital audiosystem.

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History of DAB

The European standard (Eureka-

147) was accepted as the intlstandard for DAB.

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History of DAB

China ran a trial in Fo Shan city,Guangdong province.

A trial system was set up in HK for

testing.

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The DAB system in HK

Digital Audio Broadcasting Steering Committee

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The DAB system in HK

The installation was conducted by

the

Two transmitters were set up. Onewas in Mount Gough, HK island

and the other one was in Beacon

Hill, Kowloon.

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FM Station

AM Station

Castle Peak

Cloudy

Hill

Golden

HillBeacon

Hill

Kowloon

Peak

Mount

Gough

Lamma

Island

Peng

Chau

Transmitter Site Map

DAB Station

Beacon Hill

Mt. Gough

Transmitter Site Map

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FM Station

AM Station

Castle Peak

Cloudy

Hill

Golden

HillBeacon

Hill

Kowloon

Peak

Mount

Gough

LammaIsland

Peng

Chau

Transmitter Site Map

DAB StationCoverage of

transmitter at

Mt. Gough

Coverage of

transmitter at

Beacon Hill

Transmitter Site Map

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The DAB system in HK

The project was

implemented. Only musicwas broadcasted for

testing.

First phase field test was

conducted to measure:

audio quality, bit error rate

& field strength.

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The DAB system in HK

Second phase field test was conductedto: Gather more information about mobile

reception

Explore the feasibility of text and graphicstransmission

Compare indoor receptions of DAD and FMsignals

OFTA issued DAB reports

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DABs capability:

Enhanced service and better sound

quality for audience

New market for the media sector

Audio+ Data= Digital Audio Broadcasting

FM DAB