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55-549: Digital Video Broadcasting – Satellite ( DVB-S ) is the original DVB standard for satellite television and dates from 1995, in its first release, while development lasted from 1993 to 1997. The first commercial applications were by Canal+ in France and Galaxy in Australia, enabling digitally broadcast, satellite-delivered television to the public. According to ETSI, DVB-S was the first DVB standard for satellite, defining

110-400: A Java -based platform for the development of consumer video system applications. In addition to providing abstractions for many DVB and MPEG-2 concepts, it provides interfaces for other features like network card control, application download, and layered graphics. DVB has standardized a number of return channels that work together with DVB(-S/T/C) to create bi-directional communication. RCS

165-519: A 3D TV group (CM-3DTV) to identify "what kind of 3D-TV solution does the market want and need, and how can DVB play an active part in the creation of that solution?" The CM-3DTV group held a DVB 3D-TV Kick-off Workshop in Geneva on 25 January 2010, followed by the first CM-3DTV meeting the next day. DVB now defines a new standard for 3D video broadcast: DVB 3D-TV . Modes and features of latest DVB-x2 system standards in comparison: Digital video content

220-608: A broadband content guide (DVB-BCG, ETSI TS 102 539). In October 2017, the DVB Project established a working group to begin the definition of a specification for "standalone TV services over IP, referred to as DVB-I services". Work on the commercial requirements for DVB-I began in January 2018 and the terms of reference were agreed in March 2018. The DVB-I specification, titled "Service Discovery and Programme Metadata for DVB-I",

275-614: A few ( United States , Canada , Mexico and South Korea ) have chosen ATSC instead of DVB-T. DVB-T broadcasts were launched by the President of Kenya , Mwai Kibaki on 9 December 2009. Broadcasts are using H.264 , with the University of Nairobi supplying the decoders. Kenya has also been broadcasting DVB-H since July 2009, available on selected Nokia and ZTE handsets on the Safaricom and other GSM networks. Since 2011,

330-473: A handful of commercial ones including MTV3 , Nelonen , Subtv , Jim , Nelonen Sport , Liv , FOX , TV5 Finland , AVA and Kutonen . There are also several pay channels sold by PlusTV . In Italy, DVB-S started in 1996 and the final analogue broadcasts were terminated in 2005. The switch-off from analogue terrestrial network to DVB-T started on 15 October 2008. Analogue broadcast was ended on 4 July 2012 after nearly four years of transition in phases. In

385-871: A news channel called Berita Aktif planned for inclusion in the extended trials soon. Also, high definition trials were performed during the Beijing Olympics and the outcome was also favourable. It was announced that the system would go public in 2009. In 2009, MiTV closed down, changed its name to U-Television and announced that it was changing to scrambled DVB-T upon relaunch instead of the DVB-IPTV system used prior to shutting down. However, RTM's digital network again did not go public, although around this time TVs that are first-generation DVB-T capable went on sale. The government has since announced that they will be deploying DVB-T2 instead in stages starting in mid-2015 and analog shutoff has been delayed to April 2019. In

440-500: A regional channel. Multiplexes 2~5 have the other encrypted commercial and international channels. Multiplex 1 also broadcasts the radio channels Radio 1, Radio 2, 3 FM, Radio 4, Radio 5, Radio 6, Concertzender, FunX and also a regional channel. As of June 2011, the Dutch DVB-T service had 29 TV channels and 20 radio channels (including free to air channels). DVB-T2 will be introduced during 2019/2020. In Norway , DVB-T broadcasting

495-458: A scrambled DVB program stream providing operational and commercial flexibility for the service provider. The DVB Project developed a Content Protection and Copy Management system for protecting content after it has been received ( DVB-CPCM ), which was intended to allow flexible use of recorded content on a home network or beyond, while preventing unconstrained sharing on the Internet. DVB-CPCM

550-428: A severe form of multipath propagation . The radio receiver receives several echoes of the same signal, and the constructive or destructive interference among these echoes (also known as self-interference ) may result in fading . This is problematic especially in wideband communication and high-data rate digital communications, since the fading in that case is frequency-selective (as opposed to flat fading), and since

605-402: A simulcast of both TV1 and TV2 plus a new channel called RTM3/RTMi. In April 2007, RTM announced that the outcome of the test was favourable and that it expected DVB-T to go public by the end of 2007. However, the system did not go public as planned. As of 2008, the trial digital line-up has expanded to include a music television channel called Muzik Aktif , and a sports channel called Arena, with

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660-802: A unified way. DVB-S and DVB-C were ratified in 1994. DVB-T was ratified in early 1997. The first commercial DVB-T broadcasts were performed by the United Kingdom 's Digital TV Group in late 1998. In 2003 Berlin , Germany was the first area to completely stop broadcasting analogue TV signals. Most European countries are fully covered by digital television and many have switched off PAL / SECAM services. DVB standards are used throughout Europe , as well as in Australia , South Africa and India . They are also used for cable and satellite broadcasting in most Asian , African and many South American countries. Some have chosen ISDB-T instead of DVB-T and

715-516: A variety of approaches, including: These standards define the physical layer and data link layer of the distribution system. Devices interact with the physical layer via a synchronous parallel interface (SPI), synchronous serial interface (SSI) or asynchronous serial interface (ASI). All data is transmitted in MPEG transport streams with some additional constraints (DVB-MPEG). A standard for temporally-compressed distribution to mobile devices (DVB-H)

770-399: Is a network planning aspect, in which the guard-interval is being separated into system time error and path time-error. A 100 ns step represents a 30 m difference, while 1 μs represents a 300 m difference. These distances needs to be compared with the worst-case distance between transmitter towers and reflections. Also, the time accuracy relates to nearby towers in a SFN domain, since a receiver

825-530: Is a set of international open standards for digital television . DVB standards are maintained by the DVB Project , an international industry consortium, and are published by a Joint Technical Committee (JTC) of the European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). DVB systems distribute data using

880-740: Is encoded using discrete cosine transform (DCT) based video coding standards , such as the H.26x and MPEG formats. Digital audio content is encoded using modified discrete cosine transform (MDCT) based audio coding standards , such as Advanced Audio Coding (AAC), Dolby Digital (AC-3) and MP3 . Besides digital audio and digital video transmission, DVB also defines data connections (DVB-DATA - EN 301 192) with return channels (DVB-RC) for several media ( DECT , GSM , PSTN / ISDN , satellite etc.) and protocols ( DVB-IPTV : Internet Protocol ; DVB-NPI: network protocol independent). Older technologies such as teletext (DVB-TXT) and vertical blanking interval data (DVB-VBI) are also supported by

935-510: Is facilitated by the OFDM or COFDM modulation method. OFDM uses a large number of slow low-bandwidth modulators instead of one fast wide-band modulator. Each modulator has its own frequency sub-channel and sub-carrier frequency. Since each modulator is very slow, one can afford to insert a guard interval between the symbols, and thus eliminate the ISI. Although the fading is frequency-selective over

990-579: Is marketed under RiksTV (encrypted pay channels) and NRK (unencrypted public channels). DVB-T broadcasting via the terrestrial network began in November 2007, and has subsequently been rolled out one part of the country at a time. The Norwegian implementation of DVB-T is different from most others, as it uses H.264 with HE-AAC audio encoding, while most other countries have adapted the less recent MPEG-2 standard. Notably most DVB software for PC has problems with this, though in late 2007 compatible software

1045-539: Is not expected to see the signal from transmission towers being geographically far apart, so there is no accuracy requirements between these towers. So called GPS-free solutions exist, which essentially replace GPS as the timing distribution system. Such system may provide benefit in integration with transmission system for the MPEG-2 Transport Stream. It does not change any other aspect of the SFN system as

1100-493: Is short for Return Channel Satellite , and specifies return channels in C , K u and K a frequency bands with return bandwidth of up to 2  Mbit /s. DVB-RCT is short for Return Channel Terrestrial , specified by ETSI EN 301958. The DVB-I standard (ETSI TS 103 770) defines an internet-based request and response mechanism to discover and access audiovisual services delivered over traditional digital broadcast transmissions or Internet Protocol networks and present them in

1155-627: The IRIB . DVB-T broadcasting is now widely available in other cities such as Isfahan , Mashhad , Shiraz , Qom , Tabriz and Rasht as well. DVB-T broadcasts using H.264 commenced in Israel on 1 June 2009 with the broadcast trial and the full broadcast began on 2 August 2009. Analog broadcasts were originally planned to end in 18 months after the launch, but analog broadcasts were switched off on 31 March 2011 instead. During 2010, DVB-T broadcasts have become widely available in most of Israel and an EPG

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1210-536: The Netherlands , DVB-S broadcasting started on 1 July 1996, satellite provider MultiChoice (now CanalDigitaal ) switched off the analogue service shortly after on 18 August 1996. DVB-T broadcasting started April 2003, and terrestrial analog broadcasting was switched off December 2006. It was initially marketed by Digitenne but later by KPN . Multiplex 1 contains the NPO 1 , NPO 2 and NPO 3 national TV channels, and

1265-560: The Philippines ) and in ATSC 3.0 . OFDM is also widely used in digital radio systems, including DAB , HD Radio , and T-DMB . Therefore, these systems are well-suited to SFN operation. In DVB-T a SFN functionality is described as a system in the implementation guide. It allows for re-transmitters, gap-filler transmitters (essentially a low-power synchronous transmitter) and use of SFN between main transmitter towers. The DVB-T SFN uses

1320-596: The Philippines , DVB-S and DVB-S2 are the two broadcast standards currently used by satellite companies, while DVB-C is also used by some cable companies. The government adopted DVB-T in November 2006 for digital terrestrial broadcasting but a year later, it considered other standards to replace DVB-T. The country has chosen the ISDB-T system instead of DVB-T . In Taiwan , some digital cable television systems use DVB-C, though most customers still use analogue NTSC cable television. The government planned adopting ATSC or

1375-573: The DVB-T2 standard. In Hong Kong , several cable TV operators such as TVB Pay Vision and Cable TV have already started using DVB-S or DVB-C. The government however has adopted the DMB-T/H standard, developed in mainland China , for its digital terrestrial broadcasting services which has started since 31 December 2007. On 17 March 2009, DVB-H and DVB-T H.264/AAC broadcasting started in Tehran by

1430-580: The Japanese ISDB-T standard as NTSC's replacement. However, the country has chosen the European DVB-T system instead. Public Television Service (PTS) and Formosan TV provide high definition television. The former has the channel HiHD; the latter uses its HD channel for broadcasting MLB baseball. Cyprus uses DVB-T with MPEG-4 encoding. Analogue transmission stopped on 1 July 2011 for all channels except CyBC 1 . In Denmark , DVB-T replaced

1485-505: The MPEG-2 Transport Stream forming a mega-frame. The MIP is time-stamped in the SFN adapter, as measured relative the PPS signal and counted in 100 ns steps (period time of 10 MHz) with the maximum delay (programmed into the SFN adapter) alongside. The SYNC adapter measures the MIP packet against its local variant of PPS using the 10 MHz to measure the actual network delay and then withholding

1540-444: The SFN results in ghosting due to echoes of the same signal. A simplified form of SFN can be achieved by a low power co-channel repeater , booster or broadcast translator , which is utilized as a gap filler transmitter. The aim of SFNs is efficient utilization of the radio spectrum , allowing a higher number of radio and TV programs in comparison to traditional multi-frequency network (MFN) transmission. An SFN may also increase

1595-578: The U.S. and Bell Satellite TV in Canada. While the actual DVB-S standard only specifies physical link characteristics and framing, the overlaid transport stream delivered by DVB-S is mandated as MPEG-2 , known as MPEG transport stream (MPEG-TS). Some amateur television repeaters also use this mode in the 1.2 GHz amateur band. This article related to telecommunications is a stub . You can help Misplaced Pages by expanding it . Digital Video Broadcasting Digital Video Broadcasting ( DVB )

1650-752: The UK DVB-T has been adopted for broadcast of standard definition terrestrial programming, as well as a single DVB-T2 multiplex for high-definition programming. The UK terminated all analogue terrestrial broadcasts by the end of 2012. The vast majority of channels are available free-to-air through the Freeview service. DVB-T was also used for the now-defunct ONDigital/ITV Digital and Top Up TV service. Single-frequency network Analog AM and FM radio broadcast networks as well as digital broadcast networks can operate in this manner. SFNs are not generally compatible with analog television transmission, since

1705-522: The analog transmission system for TV on 1 November 2009. Danish national digital TV transmission has been outsourced to the company Boxer TV A/S, acting as gatekeeper organization for terrestrial TV transmission in Denmark. However, there are still several free channels from DR . DVB-T transmissions were launched on 21 August 2001. The analogue networks continued alongside the digital ones until 1 September 2007, when they were shut down nationwide. Before

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1760-510: The analogue switchoff, the terrestrial network had three multiplexes: MUX A, MUX B and MUX C. MUX A contained the channels of the public broadcaster Yleisradio and MUX B was shared between the two commercial broadcasters: MTV3 and Nelonen . MUX C contained channels of various other broadcasters. After the analogue closedown, a fourth multiplex named MUX E was launched. All of the Yleisradio (YLE) channels are broadcast free-to-air, likewise

1815-631: The basic requirements can be met. While not designed with on-channel repeaters in mind, the 8VSB modulation method used in North America for digital TV is relatively good at ghost cancellation . Early experiments at WPSU-TV led to an ATSC standard for SFNs, A/110. ATSC SFNs have seen widest use in mountainous areas like Puerto Rico and Southern California , but are also in use or planned in gentler terrain. Early ATSC tuners were not very good at handling multipath propagation, but later systems have seen significant improvements. Through

1870-489: The coverage area and decrease the outage probability in comparison to an MFN, since the total received signal strength may increase to positions midway between the transmitters. SFN schemes are somewhat analogous to what in non- broadcast wireless communication, for example cellular networks and wireless computer networks, is called transmitter macrodiversity , CDMA soft handoff and Dynamic Single Frequency Networks (DSFN). SFN transmission can be considered as creating

1925-562: The fact that the guard interval of the COFDM signal allows for various length of path echoes to occur is not different from that of multiple transmitters transmitting the same signal onto the same frequency. The critical parameters is that it needs to occur about in the same time and at the same frequency. The versatility of time-transfer systems such as GPS receivers (here assumed to provide PPS and 10 MHz signals) as well as other similar systems allows for phase and frequency coordination among

1980-658: The first such platform) is used in basic packages with standard definition content, while DVB-S2 set top boxes are provided for both SD and HD content. Fully switched to digital in 2019, Russia uses the DVB-T2 standard for broadcasting 2 channel packs with about ten main national radio and TV channels ( Channel One , Rossiya 1 /2/K/24, NTV , Radio Mayak , Radio Rossii etc. Quiero TV started digital terrestrial broadcasting in 2000 as pay television . The platform closed three years later after gaining 200,000 subscribers. The frequencies used by Quiero TV were used from 2005 to simulcast free-to-air analogue broadcast as DVB-T, under

2035-469: The framing structure, channel coding and modulation for 11/12 GHz satellite services. It is used via satellites serving every continent of the world. DVB-S is used in both multiple channel per carrier (MCPC) and single channel per carrier modes for broadcast network feeds as well as for direct-broadcast satellite services like Sky UK and Ireland via Astra in Europe, Dish Network and Globecast in

2090-535: The name "TDT". The service started with 20 free-to-air national TV channels as well as numerous regional and local channels. Analogue broadcast ended on 2010 after getting 100% digital coverage. Some of the analogue frequencies were used to increase the number of channels and simulcast some of them in HD. Since February 14th, 2024, all channels will be required to broadcast exclusively in HD. Frequencies of SD channels will be used to simulcast some of them in 4K using DVB-T2. In

2145-516: The packets until the maximum delay is achieved. The details is to be found in ETSI TR 101 190 and mega-frame details in ETSI TS 101 191. It should be understood that the resolution of the mega-frame format is being in steps of 100 ns, whereas the accuracy needs can be in the range of 1-5 μs. The resolution is sufficient for the needed accuracy. There is no strict need for an accuracy limit as this

2200-621: The pay TV operator Blueline launched a DVB-T service branded BluelineTV. It supplies both smart cards and set-top-boxes. Since 1995, the pay TV operator DStv used the DVB-S standard to broadcast its services. In 2010, it started a DVB over IP service, and in 2011 it started DStv mobile using the DVB-H standard. In late 2010, the South African cabinet endorsed a decision by a Southern African Development Community (SADC) task team to adopt

2255-637: The rival DigiCipher 2 based ATSC system will not have this issue until 2048 due in part to 32 bits being used. DVB adopted a profile of the metadata defined by the TV-Anytime Forum (DVB-TVA, ETSI TS 102323). This is an XML Schema based technology and the DVB profile is tailored for enhanced Personal Digital Recorders . In the early 2000s, DVB started an activity to develop specifications for IPTV (DVB-IPI, ETSI TR 102 033, ETSI TS 102 034, ETSI TS 102 814), which also included metadata definitions for

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2310-476: The standards to ease conversion. However, for many applications more advanced alternatives like DVB-SUB for subtitling are available. The conditional access system (DVB-CA) defines a Common Scrambling Algorithm (DVB-CSA) and a physical Common Interface ( DVB-CI ) for accessing scrambled content. DVB-CA providers develop their wholly proprietary conditional access systems with reference to these specifications. Multiple simultaneous CA systems can be assigned to

2365-440: The time spreading of the echoes may result in intersymbol interference (ISI). Fading and ISI can be avoided by means of diversity schemes and equalization filters . Transmitters, which are part of a SFN, should not be used for navigation via direction finding as the direction of signal minima or signal maxima can differ from the direction to the transmitter. In wideband digital broadcasting , self-interference cancellation

2420-416: The transmitters. The guard interval allows for a timing budget, of which several microseconds may be allocated to time errors of the time-transfer system used. A GPS receiver worst-case scenario is able to provide +/- 1 μs time, well within the system needs of DVB-T SFN in typical configuration. In order to achieve the same transmission time on all transmitters, the transmission delay in the network providing

2475-504: The transport to the transmitters needs to be considered. Since the delay from the originating site to the transmitter varies, a system is needed to add delay on the output side such that the signal reaches the transmitters at the same time. This is achieved by the use of special information inserted into the data stream called the Mega-frame Initialization Packet (MIP) which is inserted using a special marker in

2530-411: The various elementary streams into coherent programs and provides human-readable descriptions for electronic program guides as well as for automatic searching and filtering. The dating system used with this metadata suffers from a year 2038 problem in which due to the limited 16 bits and modified Julian day offset used will cause an overflow issue similar to the year 2000 problem . By comparison,

2585-550: The whole frequency channel, it can be considered as flat within the narrowband sub-channel. Thus, advanced equalization filters can be avoided. A forward error correction code (FEC) can counteract some of the sub-carriers being exposed to too much fading to be correctly demodulated. OFDM is utilized in the terrestrial digital TV broadcasting system DVB-T (used in Europe and other regions), ISDB-T (used in Japan , Brazil , and

2640-662: Was added to the broadcasts. With the exception of SKY PerfecTV! , Japan uses different formats in all areas ( ISDB ), which are however quite similar to their DVB counterparts. SkyPerfect is a satellite provider using DVB on its 124 and 128 degrees east satellites. Its satellite at 110 degrees east does not use DVB, however. In Malaysia , a new pay television station MiTV began service in September 2005 using DVB-IPTV technology while lone satellite programming provider ASTRO has been transmitting in DVB-S since its inception in 1996. Free-to-air DVB-T trials began in late 2006 with

2695-885: Was approved by the DVB Project in November 2019 and first published as DVB BlueBook A177 in June 2020 and as an ETSI standard TS 103 770 in November 2020. The DVB-I specification defines ways in which devices and displays connected to the internet can discover and access sets of audiovisual media services. These can include services delivered online through fixed and wireless Internet Protocol connections as well as broadcast radio and television channels received over radio frequency networks using traditional cable , satellite , or terrestrial transmissions. Tests and pilots of DVB-I services have been undertaken in several countries including Iran, Germany, Italy, Spain and Ireland. The DVB Multimedia Home Platform (DVB-MHP) defines

2750-601: Was approved by the DVB Steering Board in June 2008 and sent to ETSI for adoption as a formal standard. ETSI adopted the standard on 9 September 2009. The DVB-T2 standard gives more robust TV reception and increases the possible bit rate by over 30% for single transmitters (as in the UK) and will increase the maximum bit rate by over 50% in large single-frequency networks (as in Germany and Sweden ). DVB has established

2805-533: Was completed on 23 July 2013. Portugal follows the DVB-T implementation, using H.264 with AAC audio encoding. It has been live since 29 April 2009 and the switch-off date for all analog signals was on 26 April 2012. Romania started digital terrestrial broadcasting in 2005 but it was virtually unknown by many people in Romania due to the lack of content, cable TV and satellite TV being far more popular, however it

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2860-590: Was published in November 2004. These distribution systems differ mainly in the modulation schemes used and error correcting codes used, due to the different technical constraints. DVB-S ( SHF ) uses QPSK , 8-PSK or 16- QAM . DVB-S2 uses QPSK, 8-PSK, 16-APSK or 32-APSK, at the broadcasters decision. QPSK and 8-PSK are the only versions regularly used. DVB-C ( VHF / UHF ) uses QAM : 16-QAM, 32-QAM, 64-QAM, 128-QAM or 256-QAM. Lastly, DVB-T (VHF/UHF) uses 16-QAM or 64-QAM (or QPSK) in combination with (C)OFDM and can support hierarchical modulation . The DVB-T2 specification

2915-424: Was released, like DVBViewer using the libfaad2 library. Sony has released several HDTVs (Bravia W3000, X3000, X3500, E4000, V4500, W4000, W4500, X4500) that support Norway's DVB-T implementation without use of a separate set-top box , and Sagem ITD91 HD, Grundig DTR 8720 STBs are others. Currently, Poland uses the DVB-T2 standard with HEVC encoding. Analogue broadcast switch-off started on 7 November 2012 and

2970-489: Was the first platform to deliver HD content. Today, Romania is using DVB-T2 as terrestrial standard, but also DVB-S/S2, and DVB-C which is extremely popular. The only analogue broadcast remains on cable. Romania adopted the DVB-T2 standard in 2016 after a series of tests with mpeg2, mpeg4 on DVB-T, and has today fully implemented DVB-T2. DVB-C, which was introduced in late 2005, still remains with mpeg2 on SD content and mpeg4 on HD content. DVB-S (introduced in 2004 focus sat being

3025-507: Was the source of much controversy in the popular press and it was said that CPCM was the DVB Project's answer to the failed American Broadcast Flag . The DVB-CPCM specifications, which were standardized by ETSI as a multipart document (TS 102 825) between 2008 and 2013, were deprecated by the DVB Steering Board in February 2019. DVB transports include metadata called Service Information (DVB-SI, ETSI EN 300 468, ETSI TR 101 211) that links

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