DVB-SH
From Wikipedia, the free encyclopedia
DVB-SH, Digital Video Broadcasting - Satellite services to Handhelds, is a physical layer standard for delivering IP based media content and data to handheld terminals such as mobile phones or PDAs, based on a hybrid satellite/terrestrial downlink and for example a GPRS uplink. The DVB Project published the DVB-SH standard in February 2007.[1]
The DVB-SH system was designed for frequencies below 3 GHz, supporting UHF band, L Band or S-band. It complements and improves the existing DVB-H physical layer standard. Like its sister specification (DVB-H), it is based on DVB IP Datacast (IPDC) delivery, electronic service guides and service purchase and protection standards.
DVB-SH specifies two operational modes:
- SH-A: specifies the use of COFDM modulation on both satellite and terrestrial links with the possibility of running both links in SFN mode.
- SH-B: uses Time-Division Multiplexing (TDM) on the satellite link and COFDM on the terrestrial link.
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[edit] Improvement of DVB-H
The DVB-SH incorporates a number of enhancements when compared to DVB-H:
- More alternative 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
Recently, results from BMCO forum[citation needed] (Alcatel April 2008) 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.
Dibcom has announced a DVB-SH chip with availability in 2008 Q3. Dibcom DVB-SH 2008 Q3. The chip "has dual RF tuners supporting VHF, UHF, L-Band and S-Band frequencies".
[edit] Project organization
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.
[edit] Trials
DVB-H/SH trials are now underway in many cities and countries: Ireland,[3] UK,[4] Malaysia, Singapore,[5] Helsinki, Berlin, Cambridge, Pittsburgh, Paris, Tehran, Madrid, Sydney,[6] South Africa, Taiwan,[7] The Hague, Brussels, Bern, Vienna, New Zealand,[8] Philippines, Copenhagen, Budapest, Erlangen,[9] and Sri Lanka.
Recently, the Indian regulator, TRAI, started to study DVB-SH as a major improvement of the DVB-H initial standard.[citation needed]
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.[10]
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.[citation needed]
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.[11]
In Italy, 3 Italia, RAI and Alcatel-Lucent joined forces for the first DVB-SH trial in Italy.[12]
In US, Dish Network and Alcatel-Lucent joined forces for the first DVB-SH trial in US.[13]
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.[citation needed]
[edit] See also
[edit] References
- ^ dvb.org: DVB approves DVB-SH specification
- ^ Alcatel Unlimited mobile TV [1] [2] [3] [4] [5] [6] [7] [8] [9]
- ^ DTG News: O2 and Arqiva launch DVB-H trial in Ireland
- ^ DTG News: UK's first DVB-H mobile TV trial goes live
- ^ Charged.mobi [10]
- ^ Dba.org.au[11]
- ^ mobile-ent.biz[12]
- ^ New Zealand Herald
- ^ DVB-H Versuchssender Erlangen
- ^ ICO Global Communications - ICO and Alcatel-Lucent Finalize Agreement for Mobile Interactive Media Services
- ^ SFR and Alcatel-Lucent tests in the field validate the fundamental assumptions for the deployment of a DVB-SH Mobile TV terrestrial network
- ^ [13]
- ^ DISH Network Corporation and Alcatel-Lucent to Perform Joint DVB-SH Test in the U.S