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| List ofdigital television broadcast standards |
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| DVB standards(countries) |
| ATSC standards(countries) |
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| ISDB standards(countries) |
| DTMB standards(countries) |
| DMB standard(countries) |
| Codecs |
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| TerrestrialFrequency bands |
| SatelliteFrequency bands |
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/terrestrialdownlink and for example aGPRS uplink. TheDVB 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 existingDVB-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.
In late 2016, it was acknowledged within the DVB Project newsletter that DVB-SH and the related DVB-H standard had been a commercial failure.[2]
There are two physical layers (terrestrial and satellite), what increases de system configuration options. Depending on the transmitted signal modulation we can find two kind of architectures: SH-A and SH-B.
Both terrestrial and satellite layers use Orthogonal frequency-division multiplexing (OFDM) this modulation solves the multipath problem, where the same token can be received multiple times with a delay due to bounces. Use OFDM in both transmitters enables creating single-frequency networks (SFN), that increases spectral efficiency but forces the terrestrial signal being identical to the transmitted by the satellite. For this reason, is permitted to implement Multi-frequency network (MFN) where terrestrial and satellite components can broadcast through different channels with the same modulation.
Terrestrial component usesOFDM but satellite uses Time-division multiplexing (TDM). Both components have to broadcast in different frequencies to avoid interference. It is not possible creatingSFN but increases satellite's signal transmission performance because TDM works better with these kinds of transmissions.
The DVB-SH incorporates a number of enhancements when compared to DVB-H:
Recently[when?], 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 byDiBcom andNXP Semiconductors, 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[permanent dead link].The chip "has dual RF tuners supporting VHF, UHF, L-Band and S-Band frequencies".
FrenchAgence de l'innovation industrielle is now[when?] financing this effort through TVMSL, a project led byAlcatel-Lucent that plans to develop a DVB-SH standard suitable for hybrid satellite and terrestrial transmission. Other partners involved in TVMSL areSagem Wireless,Alenia,RFS,Philips,DiBcom,TeamCast,UDcast,CNRS,INRIA,CEA-LETI.[3][excessive citations]
ICO, one of the biggest satellite operators in theUnited States, in 2007 announced a nationwide deployment of an hybrid satellite/terrestrial network in DVB-SH withAlcatel-Lucent[4] and Expway.[5] ICO G1 satellite carrying DVB-SH technology on board was launched on April 14, 2008. It is the world's first DVB-SH satellite in orbit.
EutelsatW2A satellite carrying aSolaris Mobile (aEutelsat andSESjoint venture, nowEchoStar Mobile) DVB-SHS band payload was launched on 3 April 2009. It will cover Western Europe.[6][7][8] S-band payload was scheduled to enter into service in May 2009 but this did not occur due to an anomaly currently being investigated.[9] On 1 July 2009, Solaris Mobile filed the insurance claim. The technical findings indicate that the company should be able to offer some, but not all of the services it was planning to offer.[10]
Inmarsat'sS band satellite programme, called EuropaSat, will deliver mobile multimedia broadcast, mobile two-way broadband telecommunications and next-generation MSS services across all member states of the European Union and as far east as Moscow and Ankara by means of a hybrid satellite/terrestrial network. It will be built byThales Alenia Space and launched in early 2011 byILS.[11]
As of February 2008[update], DVB-H/SH trials were- or had recently been- underway in many cities and countries:Ireland,[12]United Kingdom,[13]Malaysia,Singapore,[14]Helsinki,Berlin,Cambridge,Pittsburgh,Paris,Tehran,Madrid,Sydney,[15]South Africa,Taiwan,[16]The Hague,Brussels,Bern,Vienna,New Zealand,[17]Philippines,Copenhagen,Budapest,Erlangen,[18]Sri Lanka,Roeselare, andIndia.
DVB-SH in S-band is seen as an alternative in Europe. Field trials and studies showed better performance in radio than DVB-H standard that would lead to much lower costs for network deployments.[citation needed]
InFrance again,SFR andAlcatel-Lucent teamed up to deploy a DVB-SH trial. The results confirmed the theoretical assumptions on the superiority of the DVB-SH over DVB-H, being the natural evolution of this legacy technology.[19]
InItaly,3 Italia,RAI andAlcatel-Lucent joined forces for the first DVB-SH trial in Italy.[20]
InUnited States,Dish Network andAlcatel-Lucent joined forces for the first DVB-SH trial in US.[21]
Having just stood down as DVB's Chairman after eight years [..] DVB-H's failure in the market [..] the market failures of DVB-H (and DVB-SH)
{{cite web}}: CS1 maint: archived copy as title (link)"Alcatel launches global "Unlimited Mobile TV for Mass Market" project". Archived fromthe original on 2008-02-20. Retrieved2008-02-26."Sagem Communication supports Alcatel's "Unlimited Mobile TV for Mass Market" initiative". Archived fromthe original on 2008-02-20. Retrieved2008-02-26.[1]Archived 2007-10-15 at theWayback Machine[2]"Archived copy"(PDF). Archived fromthe original(PDF) on 2007-09-26. Retrieved2007-09-26.{{cite web}}: CS1 maint: archived copy as title (link)"Alcatel and DiBcom cooperate for Unlimited Mobile TV". Archived fromthe original on 2008-02-20. Retrieved2008-02-26."Alcatel and its partners welcome the support granted by the French Agency for Industrial Innovation (AII) to the "Unlimited Mobile TV" project". Archived fromthe original on 2008-02-20. Retrieved2008-02-26.[3][dead link]
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