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==DVB-SH==<!-- This section is linked from [[China Multimedia Mobile Broadcasting]] -->
==DVB-SH==<!-- This section is linked from [[China Multimedia Mobile Broadcasting]] -->
{{copypaste|February 9, 2008|section|url=http://www.dvb.org/news_events/news/dvb_approves_dvbsh_specif/index.xml}}

''DVB-SH'' is defined as a system that is able to deliver IP based media content and data to handheld terminals via satellite or terrestrial transmission. The DVB-SH system has been designed for frequencies below 3 GHz, typically the UHF, L band and S band. It complements the existing DVB-H physical layer standard and like its sister specification (DVB-H) uses the DVB IP Datacast (IPDC) set for content delivery, electronic service guide and service purchase and protection standards.
''DVB-SH'' is defined as a system that is able to deliver IP based media content and data to handheld terminals via satellite or terrestrial transmission. The DVB-SH system has been designed for frequencies below 3 GHz, typically the UHF, L band and S band. It complements the existing DVB-H physical layer standard and like its sister specification (DVB-H) uses the DVB IP Datacast (IPDC) set for content delivery, electronic service guide and service purchase and protection standards.
DVB-SH includes features such as turbo coding for forward error correction and a highly flexible interleaver in an advanced system designed to cope with the hybrid satellite/terrestrial network topology. Satellite transmission (if any) ensures wide area coverage, with a terrestrial component assuring coverage where the satellite signal cannot be received (or where there is simply no satellite available), as may be the case in built-up areas (indoor coverage). DVB-SH in fact specifies two operational modes. SH-A specifies the use of COFDM on both satellite (if any) and terrestrial links with the possibility of running both links in SFN mode. SH-B uses a Time Division Multiplexing (TDM) on satellite (if any) with COFDM on the terrestrial link. The [[DVB|DVB Project]] approved the definitive standard in February 2007.<ref>[http://www.dvb.org/news_events/news/dvb_approves_dvbsh_specif/index.xml dvb.org: DVB approves DVB-SH specification]</ref>
DVB-SH includes features such as turbo coding for forward error correction and a highly flexible interleaver in an advanced system designed to cope with the hybrid satellite/terrestrial network topology. Satellite transmission (if any) ensures wide area coverage, with a terrestrial component assuring coverage where the satellite signal cannot be received (or where there is simply no satellite available), as may be the case in built-up areas (indoor coverage). DVB-SH in fact specifies two operational modes. SH-A specifies the use of COFDM on both satellite (if any) and terrestrial links with the possibility of running both links in SFN mode. SH-B uses a Time Division Multiplexing (TDM) on satellite (if any) with COFDM on the terrestrial link. The [[DVB|DVB Project]] approved the definitive standard in February 2007.<ref>[http://www.dvb.org/news_events/news/dvb_approves_dvbsh_specif/index.xml dvb.org: DVB approves DVB-SH specification]</ref>

Revision as of 12:05, 9 February 2008

The DVB organization has been developing technical specifications for bringing broadcast services to mobile handsets first with DVB-H and DVB-SH. DVB-H (Digital Video Broadcasting - Handheld) was the first to be implemented. 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.[1] DVB-H (and DVB-SH for the satellite access) is officially endorsed by the European Union.[2][3][4] The major competitor of this technology is Digital Multimedia Broadcasting (DMB). DVB-SH now and DVB-H2 in the future are natural enhancement of this technology with impressive radio improvements and better modulation flexibility. The DVB Project approved the definitive DVB-SH standard in February 2007.[5]

DVB-H

DVB-H Frame structure

DVB-H technology is a superset of the very 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.

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 recently improved dramatically radio performances and is seen as an evolution of DVB-H.

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-H2 in the near future will expand the supported bands.

DVB-H can coexist with DVB-T in the same multiplex.

DVB-IPDC

The set of DVB specifications for IP Datacasting (DVB-IPDC) can most simply be described as the essential components required to deploy a commercial mobile TV service 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-H2

A study mission on a possible DVB-H2 system is due to commence in 2007 which could produce a finalized specification in 2008. It is not unthinkable that DVB-H2 and DVB-T2 specifications will be interrelated systems.

DVB-SH

DVB-SH is defined as a system that is able to deliver IP based media content and data to handheld terminals via satellite or terrestrial transmission. The DVB-SH system has been designed for frequencies below 3 GHz, typically the UHF, L band and S band. It complements the existing DVB-H physical layer standard and like its sister specification (DVB-H) uses the DVB IP Datacast (IPDC) set for content delivery, electronic service guide and service purchase and protection standards. DVB-SH includes features such as turbo coding for forward error correction and a highly flexible interleaver in an advanced system designed to cope with the hybrid satellite/terrestrial network topology. Satellite transmission (if any) ensures wide area coverage, with a terrestrial component assuring coverage where the satellite signal cannot be received (or where there is simply no satellite available), as may be the case in built-up areas (indoor coverage). DVB-SH in fact specifies two operational modes. SH-A specifies the use of COFDM on both satellite (if any) and terrestrial links with the possibility of running both links in SFN mode. SH-B uses a Time Division Multiplexing (TDM) on satellite (if any) with COFDM on the terrestrial link. The DVB Project approved the definitive standard in February 2007.[6]

File:DVB-SH frequencies.jpg
DVB-SH supported spectrum

French Agence de l'innovation industrielle is now financing this effort through TVMSL, a project led by Alcatel-Lucent that plans to develop a DVB-SH standard suitable for hybrid satellite and terrestrial transmission. Other partners involved in TVMSL are Sagem, Alenia, RFS, Philips, DiBcom, TeamCast, UDcast, CNRS, INRIA, CEA-LETI.


The DVB-SH incorporates a number of changes compared to DVB-H:

  • More ratios on coding rates are available
  • The omission of the 64QAM modulation scheme
  • The inclusion of support for 1.7 MHz bandwidth and 1k FFT
  • FEC using Turbo coding
  • Improved time interleaving
  • Support for antenna diversity in terminals


File:DVB-SH radio.jpg
DVB-SH radio improvements in UHF

Recently, results from BMCO forum shows a radio improvement of at least 5.5 dB on signal requirements between DVB-H and DVB-SH in the UHF frequencies. The improvements to signal requirements translates to better in-building penetration, better in-car coverage and extension of outdoor coverage. DVB-SH Chipsets are being developed now by Dibcom and NXP, and are expected to be available in beginning of 2008. Initial specifications show that the chipsets supports both UHF and S-Band and are compatible with DVB-H.

[7]






Trials

DVB-H/SH trials are now underway in many cities and countries: Ireland,[8] UK,[9] Malaysia, Singapore,[10] Helsinki, Berlin, Cambridge, Pittsburgh, Paris, Tehran, Madrid, Sydney,[11] South Africa, Taiwan,[12] The Hague, Brussels, Bern, Vienna, New Zealand,[13] Philippines, Copenhagen, Budapest, Erlangen,[14] and Sri Lanka.

A comprehensive list of DVB-H trials and service launches is available from dvb-h.org.

Service launches

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 1st 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[15]. However, recently the Indian regulator, TRAI, started to study DVB-SH as a major improvement of the DVB-H initial standard.

In Italy, 3 Italia launched nationwide services in May 2006, both Telecom Italia Mobile (TIM) and Mediaset in June 2006, Vodafone in December 2006. DVB OSF was the adopted security standard in this country.

In Singapore, TVMobile uses DVB technology to broadcast live news, entertainment and music content directly to over 1500 Singapore Bus Service buses islandwide, along with various other indoor and outdoor locations.

In the Philippines, SMART had launched its Mobile TV services, called MyTV. It is only available on the Nokia N92 mobile phone due to incompatibility of the current system with other security technologies such as DVB OSF, the one supported by all other handsets 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.[16] [17]

In the United States, a nationwide service will be rolled out by Modeo a company owned by Crown Castle. The service will begin in 2006 in New York City and will roll out to the top thirty markets in the USA during 2007. Modeo owns 5 MHz of spectrum nationwide at 1600 MHz. At the NAB trade show in April 2006, a second service launch was announced by SES Americom and Aloha Partners. 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.
ICO, one of the biggest satellite operator in the United States, recently announced a nationwide deployment of an hybrid satellite/terrestrial network in DVB-SH with Alcatel-Lucent.[18]

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, in Austria, Germany and Switzerland for 2009. However, the unavailability of the UHF frequencies keeps on delaying services launches. DVB-SH in S-band is seen as a alternative in Europe. Recent field trials and studies showed better performance in radio than DVB-H standard that would lead to much cheaper costs for network deployments.

In France again, SFR and Alcatel-Lucent teamed up to deploy a DVB-SH trial. The results confirmed the theorical assumptions on the superiority of the DVB-SH to DVB-H, being the natural evolution of this legacy one.[19]

In Italy, 3 Italia, RAI and Alcatel-Lucent joined forces for the first DVB-SH trial in Italy.[20]

In China, two companies have been issued licenses by the government, Shanghai Media Group and China Central Television. Trials are currently underway, with service launch expected before the 2008 Beijing Olympics. However, in this country, S-timi seems to be 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.[21]
Maxis/Astro, the biggest telecom operator in the country, is seeing in their side DVB-SH as today the best and most advanced standard for Mobile TV Broadcast in Malaysia.[22]

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.

Devices

Development tools

  • The open-source AMUSE DVB-H tools[24] are capable of generating a DVB-H signal from one or more IP streams.

See also

References

  1. ^ http://www.dvb-h.org/
  2. ^ http://ec.europa.eu/information_society/newsroom/cf/itemlongdetail.cfm?item_id=3535
  3. ^ http://ec.europa.eu/information_society/policy/ecomm/doc/info_centre/communic_reports/mobile_tv/acte_en.pdf
  4. ^ http://www.iht.com/articles/ap/2007/07/18/business/EU-FIN-EU-Mobile-Broadcasting.php
  5. ^ dvb.org: DVB approves DVB-SH specification
  6. ^ dvb.org: DVB approves DVB-SH specification
  7. ^ Alcatel Unlimited mobile TV [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12]
  8. ^ http://www.dtg.org.uk/news/news.php?id=2298
  9. ^ http://www.dtg.org.uk/news/news.php?id=1180
  10. ^ Charged.mobi [13]
  11. ^ Dba.org.au[14]
  12. ^ mobile-ent.biz[15]
  13. ^ New Zealand Herald
  14. ^ [16]
  15. ^ [17]
  16. ^ About SMART MyTV
  17. ^ [18]
  18. ^ [19]
  19. ^ [20]
  20. ^ [21]
  21. ^ Official Press Release Announcement by U Mobile[22]
  22. ^ [23]
  23. ^ http://www.unregisterednews.com/content/view/312/9/
  24. ^ AMUSE DVB-H tools
  • DVB-H.org - Official DVB-H website of the DVB Project, includes extensive information on trials, technical specifications for download, a detailed FAQ, and an indication of DVB-H related products
  • DVB Project - Official DVB website
  • DVB Fact Sheets including Fact Sheets covering DVB-H, DVB-SH and DVB-IPDC
  • ETSI - DVB-H specifications available for download
  • Mobile DTV Alliance - Information about DVB-H activities in North America and the Mobile DTV Alliance

Technical information

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