Page 88 - DCAP303_MULTIMEDIA_SYSTEMS

Multimedia Systems

notes The resulting organization was named the Electronics Launching Group (ELG), and it developed
a memorandum of understanding that was signed in 1993. At the same time it renamed itself the
DVB Project, and the development of the technologies and standards started to move forwards
with a swifter pace.

The first of the DVB standards to be agreed was the DVB-S standard for satellite transmission
which was agreed in 1994. With the standard agreed, services were commenced in early 1995 and
the first operator was the pay TV operator Canal Plus in France.
The DVB system used for terrestrial transmissions, DVB-T was agreed later, in 1997. The first
countries to deploy the system were Sweden, launching their system in 1998, and the UK launching
their system a year later.
5.5.3 integrated services Digital Broadcasting (isDB)

Integrated Services Digital Broadcasting (ISDB) is a Japanese standard for DTV and digital radio
used by the country’s radio and television stations. The ISDB replaced the previously used MUSE
“Hi-vision” analogue HDTV system. A derivative of ISDB, ISDB-T International, was developed
by the Brazilian government and is being widely adopted in South America.
The core standards of ISDB are ISDB-S (satellite television), ISDB-T (terrestrial), ISDB-C (cable)
and 2.6 GHz band mobile broadcasting which are based on MPEG-2 video and audio coding as
well as the transport stream described by the MPEG-2 standard, and are capable of high-definition
television (HDTV). The ISDB-T and ISDB-Tsb are for mobile reception in TV bands. The 1seg is
the name of an ISDB-T service for reception on cell phones, laptop computers and vehicles.

Japan started digital broadcasting using the DVB-S standard by PerfecTV in October 1996,
and DirecTV in December 1997, with communication satellites. Still, DVB-S did not satisfy the
requirements of Japanese broadcasters, such as NHK, key commercial broadcasting stations
like Nippon Television, TBS, Fuji Television, TV Asahi, TV Tokyo and WOWOW (Movie-only
Pay-TV broadcasting). Consequently, ARIB developed the ISDB-S standards. The requirements
were HDTV capability, interactive services, network access and effective frequency utilization,
and other technical requirements. The DVB-S standard allows the transmission of a bit stream
of roughly 34 M bit/s with a satellite transponder, which means the transponder can send one
HDTV channel. Unfortunately, the NHK broadcasting satellite had only four vacant transponders,
which led ARIB and NHK to develop ISDB-S: The new standard could transmit at 51 M bit/s
with a single transponder, which means that ISDB-S is 1.5 times more efficient than DVB-S and
that one transponder can transmit two HDTV channels, along with other independent audio and
data. Digital satellite broadcasting (BS digital) was started by NHK and followed commercial
broadcasting stations on 1 December 2000. Today, SKY PerfecTV!, successor of Skyport TV, and
Sky D, CS burn, Platone, EP, DirecTV, J Sky B, and PerfecTV!, adopted the ISDB-S system for use
on the 110 degree (east longitude) wide-band communication satellite.

5.5.4 List of Countries used these standards
DvB
Australia

Standard: DVB-T
Frequencies: UHF and VHF,
Compression: HD and SD in MPEG2

Channel bandwidth: 7 MHz
Carrier type: 8 k
Modulation: 64 QAM

82 LoveLy professionaL University