1) Australia began researching digital terrestrial television broadcasting (DTTB) in the mid-1980s and decided in the early 1990s to develop DTTB that paralleled the existing analog television structure. 2) In 1998, Australian broadcasters began developing industry practices for delivering standard definition (SDTV) and high definition (HDTV) content for DTTB, specifying quality standards. Transmissions began in 2001 in metropolitan areas and 2003 in regional areas. 3) The development of DTTB in Australia included establishing transmission standards based on DVB-T, developing digital channel plans, promoting consumer awareness of DTTB benefits, and managing interference issues during the transition to DTTB.

1. ITU News 2/2004 1
FROM ANALOGUE TO DIGITAL TELEVISION THE AUSTRALIAN WAY TO
DTTB
The Australian Way to DTTB
Background
Australia has been involved in the debates on
digital terrestrial television broadcasting (DTTB),
including high-definition television (HDTV), since
the mid-1980s. Particular attention has been paid
to the International Telecommunication Union‘s
Radiocommununication Sector (ITU–R) forums,
where Australian experts have consistently
pressed for common international standards. ITU
was seen as the main forum in which to argue for
convergence of television standards for new
technology choices to avoid the need for
continuing standards conversion and consequent
operational and quality difficulties.
By the early 1990s, Australia had decided that
the most appropriate path to digital television for
the Australian industry was in developing
terrestrial digital broadcasting parallelling the existing mature analogue television
structure. Robust reception and HDTV were seen as key elements in promoting the
development of digital television broadcasting.
Development of content and transmission characteristics for DTTB
Industry operational practice for delivery of SDTV and HDTV material to the Australian
terrestrial broadcast industry
In 1998, Australian terrestrial broadcasters commenced
development of industry operational practices for the
delivery of standard definition television (SDTV) and HDTV
programme material. These broadcasters were required to
introduce digital transmissions at nominal standard and
high definition resolutions with an image aspect ratio of
16:9; and parallel analogue PAL 4:3 services were to
continue in operation for a period which at the time was
not determined.
The new digital high definition service of aspect ratio 16:9 was to be serviced by both
original 16:9 high definition progamming and standard definition 16:9 programme
material via an up conversion process. This placed significant demands on the quality of
the programme material, especially with respect to spatial resolution. Historically, much
programme materialfrom the past has not been suitable for new services. In the case of
both the up and down conversions, it has been essential for the luminance and
chrominance values to be transferred accurately from one resolution level to the other.
For transmission in the HD digital service, the programme materialwas to be subjected to
MPEG-2 video compression at high compression ratios. This places a significant demand on
Roger Bunch
Director of Engineering
Commercial Television Australia
Australian commercial and
national broadcasters
commenced digital
transmissions on 1 January
2001 in metropolitan
areas. Regional
broadcasters commenced
rolling out DTTB services
prior to 1 January 2004

2. ITU News 2/2004 2
the quality of the programme materialwith respect to video signal to noise ratio and
image stability.
On the very important issue of standards conversion, it was necessary in the transition to
high definition to maintain the current situation of temporal artefact free conversions,
from both film and video-originated programme material.
Two important industry practices were developed that specify the quality for the
international and national exchange of programmes and commercials in both SDTV and
HDTV formats. One is the "Operational Practice OP30 Quality specification for the
international and national exchange of programmes in SDTV and HDTV formats". The
other is "Operational Practice OP36 — SDTV and HDTV Commercials — Videotape
Delivery". Both recommend the format and quality of the video and audio associated with
programme materialdelivered to the Australian terrestrial broadcast industry. Their
references are to content of both film and video camera origin. They provide the
following specifications to producers of programme materialto Australian broadcasters:
 Delivery specifications
 Video requirements
 Subjective video quality
 Subjective audio quality
 Sequence of alignment signals
 Time and control code
 Closed captions
 SDTV and HDTV safe action and safe graphic areas.
Development of the transmission characteristics for DTTB
In 1998, the Australian national standards body, Standards Australia, in conjunction with
terrestrial television broadcasters, receiver manufacturers and regulatory bodies
commenced development of a terrestrial television transmission standard for Australia.
The objective was to provide television receiver manufacturers and broadcasters with the
technical specification for the Australian digital terrestrial television transmission system
in order to achieve interoperability in DTTB transmission and reception.
Digital video broadcasting — terrestrial (DVB-T) was selected in 1998 as the Australian
transmission standard for the DTTB system. DVB-T was to be adapted where necessary to
meet Australia’s specific requirements. When published in 2000 as "AS 4599", this
standard not only stated that DVB specifications and standards of the European Technical
Standards Institute (ETSI) provide a range of possible specifications, but it also listed the
variations specific to Australian regulatory and legislative requirements of most
importance. For example:
 7 MHz channels were to be used both at VHF and UHF.
 Australian broadcasters would implement single frequency networks.
 Transmissions could include video MPEG-2 encoded at 25 frames, 50 fields per
second. The video could be scanned up to 1920 pixels by 1080 lines.
 Broadcasters are required to meet quotas relating to HDTV programme content.
 Transmissions could include closed caption subtitles based on either or both ETSI
standards EN 300 473 and ETS 300 742.
 Transmissions may include data broadcasting as specified in EN 301 192.

3. ITU News 2/2004 3
 Transmission filter masks for Australia’s 7 MHz channel spacing would take into
account the relative proximity of lower adjacent channel dual analogue sound
carriers compared with a less stringent 8 MHz channel spacing.
DTV receiver testing and conformance
Australian terrestrial television broadcasters realized they were one of the pioneers of
"horizontal" implementation of DVB-T. Within the "vertical" implementations of the DVB
standards to date, individual organizations and multiplex operators had developed
specifications for receivers. In Australia’s "horizontal" implementation, there was the
possibility in some licence areas to be serviced by up to ten broadcasters, each with their
own multiplex and a viewing audience supplied with receivers from a larger number of
sources.
The industry commenced the development of DTTB reference transport streams for the
testing of television receivers in a broadcast environment. The streams were
representative of the broadcast signals to be provided by Australian DTTB transmissions
and specifications within the AS4599. These streams have been made available to at least
40 organizations who have tested broadcasting and consumer electronics equipment
against the Australian transmission standard, AS4599.
Recently, the Australian industry has been discussing the establishment of a DTV test and
conformance centre, the function of which will be particularly important with the
introduction of interactive television services. Some broadcasters have already started
trialling interactive services.
Digital channel planning
The Australian Broadcasting Authority (ABA) developed digital
channel plans, or DCPs, for Australia. These plans determined
which channels were to be allotted to each broadcaster and the
technical characteristics of those channels. ABA’s objective was to
plan the channel allotments to enable a broadcast licensee to plan
its digital transmission coverage to achieve the same coverage as its analogue service.
Each DCP plans for a minimum of seven digital television channels corresponding to the
five analogue services to be converted to digital in each area and additional capacity
(typically two channels) for future services.
Fundamental to the development of the DCPs was the general and technical assumptions
developed by ABA in conjunction with the Communications Laboratory of the Department
of Communications Information Technology and the Arts and the broadcasting industry.
These are contained in ABA’s Digital Terrestrial Television Broadcasting Planning
Handbook.
Under the terms of the Digital Conversion Schemes (also developed by the ABA),
implementation plans are to be submitted by broadcast licensees which outline how that
licensee’s digital services from specified sites will cover specified areas by specified dates
so as to achieve the same coverage requirement.
Australian commercial and national broadcasters commenced digital transmissions on 1
January 2001 in metropolitan areas. Regional broadcasters commenced rolling out DTTB
services prior to 1 January 2004. There is to be a simulcast period of at least eight years
throughout which broadcasters must transmit their television programmes in both
Sales of digital
television set-top
box receivers are
mirroring the sales
of widescreen
televisions...

4. ITU News 2/2004 4
analogue and digital mode. Provision has been made for digital datacasting services. A
trial datacasting service commenced in Sydney in December 2003.
During the conversion to DTTB, the broadcasting industry recognized the importance of
consumer awareness of the benefits of digital television. The industry established Digital
Broadcasting Australia (DBA) to promote DTV through cross-industry forums and develop
public relations and marketing campaigns to encourage consumers to convert to digital
television.
The conversion to DTTB has required the development of strategies to address
interference issues, which arose as a result of the introduction of digital services and the
potential interference to the adjacent analogue service and consumer electronic products
tuned to the same frequency as the digital service. Broadcasters undertook a series of
public awareness campaigns and developed education strategies as part of an
interference assistance scheme. This has minimized disruption to consumers.
The free-to-air broadcasters are now transmitting their digital television services in all
capital cities (Sydney, Melbourne, Brisbane, Adelaide, Perth, Hobart, Canberra and
Darwin) and a number of major regional markets, 24 hours a day, seven days a week. A
number of legislative and regulatory reviews on the conversion to DTTB are to be
conducted in 2004 and 2005.
Receiver availability
There are approximately 7.1 million television homes in Australia. Based on cumulative
sales of digital terrestrial set-top boxes and integrated digital televisions to retailers and
installers, digital TV receiver sales to December 2003 were 250 000 units. DBA predicts
sales of more than 350 000 digital TV set-top box receivers and integrated digital
televisions in 2004. Sales of digital television set-top box receivers are mirroring the sales
of widescreen televisions (CRTs, rear projection, Plasma and LCD), which reached a
record 26 000 units in October 2003. The types of receivers available include both
standard definition and high definition set-top boxes, integrated digital TV receivers and
PC video cards.
In 2002, the Australian consumer electronics industry developed a marketing code for DTV
receivers to ensure consistency in the nomenclature used for DTV products. This code has
been produced in order to provide information on the performance characteristics of
digital TV broadcast receivers and display devices. The document has a primary role to
educate through providing accurate descriptors of analogue and digital television
receivers and display devices.
Conclusion
Implementation of DTTB in Australia has been based upon exhaustive research and
maintenance of a series of robust and evolving standards. The "tool- box" approach of
these standards has permitted Australian broadcasters to develop a flexible range of
transmission characteristics in a horizontal market, while not prejudicing, in the main, a
stable deployment of consumer electronics products.