DVB-H
(Digital Video Broadcasting - Handheld) is one of three prevalent
mobile TV formats. It is a technical specification for bringing
broadcast services to mobile handsets. DVB-H was formally adopted as
ETSI standard EN 302 304 in November 2004. The DVB-H specification (EN
302 304) can be downloaded from the official DVB-H website. From March
2008, DVB-H is officially endorsed by the European Union as the
"preferred technology for terrestrial mobile broadcasting". The major
competitors of this technology are Qualcomm's MediaFLO system, the 3G
cellular system based MBMS mobile-TV standard, and the ATSC M/H format
in the U.S. DVB-SH (Satellite to Handhelds) now and DVB-NGH (Next
Generation Handheld) in the future are possible enhancements to DVB-H,
providing improved spectral efficiency and better modulation
flexibility.
1 Technical explanation
2 DVB-IPDC
3 DVB-NGH
4 DVB-SH
5 Service launches
6 Devices
7 Development tools
8 See also
9 References
10 External links
Technical explanation
DVB-H technology is a superset of the
successful DVB-T (Digital Video Broadcasting - Terrestrial) system for
digital terrestrial television, with additional features to meet the
specific requirements of handheld, battery-powered receivers. In 2002
four main requirements of the DVB-H system were agreed: broadcast
services for portable and mobile usage with 'acceptable quality'; a
typical user environment, and so geographical coverage, as mobile radio;
access to service while moving in a vehicle at high speed (as well as
imperceptible handover when moving from one cell to another); and as
much compatibility with existing digital terrestrial television (DVB-T),
to allow sharing of network and transmission equipment.
DVB-H can offer a downstream
channel at high data rates which can be used as standalone or as an
enhancement of mobile telecommunication networks which many typical
handheld terminals are able to access anyway.
Time slicing technology is
employed to reduce power consumption for small handheld terminals. IP
datagrams are transmitted as data bursts in small time slots. Each burst
may contain up to two megabits of data (including parity bits). There
are 64 parity bits for each 191 data bits, protected by Reed-Solomon
codes. The front end of the receiver switches on only for the time
interval when the data burst of a selected service is on air. Within
this short period of time a high data rate is received which can be
stored in a buffer. This buffer can either store the downloaded
applications or playout live streams.
The achievable power saving
depends on the relation of the on/off-time. If there are approximately
ten or more bursted services in a DVB-H stream, the rate of the power
saving for the front end could be up to 90%. DVB-H is a technical system
which was carefully tested by the DVB-H Validation Task Force in the
course of 2004 (see ETSI Technical Report TR 102 401). DVB-SH improved
radio performances and can be seen as an evolution of DVB-H.
DVB-H Frame structure
DVB-H is designed to work in the following bands:
VHF-III (170-230 MHz, or a portion of it)
UHF-IV/V (470-862 MHz, or a portion of it)
L (1.452-1.492 GHz)
DVB-SH now and DVB-NGH in the near future are expected to expand the supported bands.
DVB-H can coexist with DVB-T in the same multiplex.
DVB-IPDC
DVB-IPDC (DVB for IP
Datacasting) is the specification for broadcasting mobile TV services
based on Internet Protocol. DVB-IPDC is a set of systems layer
specifications originally designed for use with the DVB-H physical
layer, but that will ultimately be used as a higher layer for all DVB
mobile TV systems, including DVB-SH, and indeed as a higher layer for
any other IP capable system.
In short, with regard to mobile
TV, these specifications define what is delivered, how it is delivered,
how it is described, and how it is protected. They cover system
architecture, use cases, DVB PSI/SI signalling, electronic service guide
(ESG), content delivery protocols (CDP), and service purchase and
protection (SPP). Almost all of these have now been published as formal
ETSI standards. The full set of DVB-IPDC specifications is available
from dvb-h.org.
DVB-NGH
In 2007 a study mission was
formed to investigate the options for a potential DVB-H2 successor to
DVB-H, but the project was later shelved.
In
November 2009, the DVB group made a 'call for technologies' for a new
system (DVB-NGH - Next Generation Handheld) to update and replace the
DVB-H standard for digital broadcasting to mobile devices.[8] The
schedule was for submissions to be closed in February 2010, the new ETSI
standard published in 2011, and rollout of the first DVB-NGH devices
from 2013.[8]
DVB-SH
Main article: DVB-SH
The DVB-SH (Satellite services
to Handheld) standard was published in February 2007. Trials are ongoing
in several European countries.
Service launches
This
article is outdated. Please update this article to reflect recent
events or newly available information. Please see the talk page for more
information. (November 2010)
A comprehensive list of DVB-H trials and service launches is available from dvb-h.org.
In
Finland, the license to operate a DVB-H network was awarded to Digita
in March 2006. In May 2006 they announced that they had signed a
contract with Nokia to use its DVB-H platform for the service. The
network was supposed to be launched on the 1 December 2006, but
disagreements regarding copyrights of the broadcasted material have
stalled the launch. Among the services available will be Voice TV and
Kiss digital radio. Initially the network should cover 25% of the
population with coverage area Helsinki, Oulu and Turku. Mobiili-TV
started commercial services on May 10, 2007.
In India, Indian public
broadcaster Prasar Bharti (also known as DD for Doordarshan) started
DVB-H trials in various metropolitan areas to test the reception quality
of the broadcast coverage. Moreover, DD is currently broadcasting 8
channels in the New Delhi.
In Italy, 3 Italia and Reti
Radiotelevisive Digitali[10] launched nationwide services in May 2006
(technology used[11]), both Telecom Italia Mobile (TIM) and Mediaset in
June 2006, Vodafone in December 2006. DVB OSF was the adopted security
standard in this country. Since June 2008, 3 Italia has made some
channels free on Dvb-h for all the users.
In Singapore, M1, StarHub,
Singtel and Mediacorp launches for Beijing Olympics a nationwide DVB-H
pilot adopting OMA BCAST SmartCard profile.
In the Philippines, SMART had
launched its Mobile TV services, called MyTV. It is only available on
the Nokia N92 and N77 mobile phone due to incompatibility of the current
system with other security technologies such as DVB OSF, the one
supported by all other handset manufacturers. However, with transition
to OMA SmartCard Profile, it is yet to be available on other mobile
phones models. This transition is not foreseen by end of 2008.
In the United States, Crown
Castle had rolled out a DVB-H offering through a company they created
called Modeo in 2006. It was initially offered in New York, but it was
eventually terminated in 2007. Modeo was attempting to compete
head-to-head with MediaFLO; which is both a Mobile TV company and Mobile
TV Standard created by Qualcomm.
At the NAB trade show in April
2006, a second service launch was announced by SES Americom, Aloha
Partners and Reti Radiotelevisive Digitali. Titled Hiwire Mobile
Television, the service is set to begin trials in Las Vegas in Q4 2006.
Hiwire owns two 6 MHz channels of spectrum at 700 MHz covering most of
the country.
In Albania, DigitAlb and
GrassValley launched the service on December 20, 2006 with free access
up to the end of 2008. The package consists of 16 channels and covers
65% of the territory as of August 2007.
In Vietnam, VTC launched
nationwide service on 21 December 2006. Similar issue to Smart in
Philippines, the system was supporting only few Nokia handsets that
limited the take-off of the service.
O2 Ireland commenced a trial in
March 2007 with a single high site 1.2 kW transmitter at Three Rock
covering the greater Dublin area.
In France, Spain and South
Africa nationwide service launch is planned for 2008 or 2009, However,
the unavailability of the UHF frequencies keeps on delaying services
launches.
In Austria DVB-H is available
since the start of UEFA Euro 2008 as result of a joint effort between
Media Broad and the mobile operators Three and Orange.
In Morocco, the service has been launched in May 2008.
In Switzerland DVB-H is available since the start of UEFA Euro 2008 thanks to Swisscom.
In
Germany the future of DVB-H is still unknown due to continuous issues
with the license and open questions about the business model, in
particular which role operators play in it and if they are willing to do
so.
In China, two companies have
been issued licenses by the government, Shanghai Media Group and China
Central Television. Trials are currently underway, services were
expected to be launched before the 2008 Beijing Olympics. However, in
this country, China Multimedia Mobile Broadcasting (CMMB) is the
standard the most deployed in 2008.
In Malaysia, U Mobile, the
fourth telecom operator and the country's newest 3G service provider
announced commercial availability of a mobile broadcast TV service based
on DVB-H technology before the end of 2007. The service will be called
Mobile LiveTV.
Kenya has a DVB-H service, DStv
Mobile, which was launched in Nairobi by South African company Digital
Mobile TV. Consumers will receive a package of ten DStv channels through
their mobile phones at a cost of Sh1,000 per month. The channels will
include SuperSport Update, SuperSport 2, SuperSport 3, CNN
International, Big Brother Africa and Africa Magic.
In Iran, DVB-H services began in
Tehran in March 2008. The service brings ten television and four radio
channels to mobile phones.
In Estonia, DVB-H service
started testing phase in May 2008 with Levira and EMT. Currently
offering 15 TV-stations, the service should go into commercial use later
next year.
In South Africa Multihoice launched the public version of its DVB-H service, called DSTV Mobile on the 1st December 2010
In the Netherlands, KPN launched
a DVB-H service on the 29th of May 2008. The service offers 10
channels, 1 channel specially made for the service and 9 channels which
are converted regular broadcasts On the 30th of March 2011, KPN
announced it was terminating the DVB-H service on June 1st 2011 because
of a lack of new mobiles supporting the standard which resulted in less
users. KPN still believes in mobile video, but in the form of
video-on-demand using mobile internet connections
Devices
E-TEN - glofiish V900
Garmin - nuvi 900T (Italy only)
Gigabyte - GSmart t600, GSmart q60 (all with DVB-T, DVB-H, T-DMB and DAB)
LG - U900, KB620, KU950, U960, KB770, HB620T
Motorola - A680i
Nokia
- 7710 (experimental DVB-H version), N92, N77, N96,[20] Nokia SU-33W
(External Bluetooth DVB-H receiver), Nokia 5330 Mobile TV Edition
(DVB-H), Nokia N8[21][22]
Samsung - SGH-P910, SGH-P920, SGH-P930, SGH-P940, SGH-P960, SGH-F510
Philips - HotMAN2
Sagem - My Mobile TV, My Mobile TV2
ZTE - N7100, F908 (clamshell), F912 (clamshell), F928(slider launched in Q3, 2008), F900 (launched in Q1, 2009)
Development tools
The open-source AMUSE DVB-H tools[23] are capable of generating a DVB-H signal from one or more IP streams.
ATSC-M/H U.S. mobile/handheld standard
Digital Audio Broadcasting (DAB and DAB+)
Digital Multimedia Broadcasting (DMB)
Digital Radio Mondiale (DRM)
Electronic program guide
ETSI Satellite Digital Radio (SDR)
E-VSB ATSC standard
Handheld projector
Integrated Services Digital Broadcasting (ISDB)
IP over DVB
DVB over IP
MediaFLO
Mobile DTV Alliance industry association
Mobile TV a term for the entire category
Multimedia Broadcast Multicast Service (MBMS)
OFDM system comparison table - providing technical details
OneSeg
Spectral efficiency comparison table
WiMAX
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