ISDB
Integrated Services Digital Broadcasting Japanese Broadcasting Standard
Integrated Services Digital Broadcasting is a Japanese broadcasting standard for digital television (DTV) and digital radio.
Integrated Services Digital Broadcasting
Company type Incentive
Founded 1981
Headquarters Japan
ISDB supersedes both the NTSC-J analog television system and the previously used MUSE Hi-vision analog HDTV system in Japan. An improved version of ISDB-T (ISDB-T International) will soon replace the NTSC, PAL-M, and PAL-N broadcast standards in South America and the Philippines. Digital Terrestrial Television Broadcasting (DTTB) services using ISDB-T started in Japan in December 2003, and since then, many countries have adopted ISDB over other digital broadcasting standards.
A newer and "advanced" version of the ISDB standard (that will eventually allow up to 8K terrestrial broadcasts and 1080p mobile broadcasts via the VVC codec, including HDR and HFR) is currently under development.
ISDB is maintained by the Japanese organization ARIB. The standards can be obtained for free at the Japanese organization DiBEG website and at ARIB.
The core standards of ISDB are ISDB-S (satellite television), ISDB-T (terrestrial), ISDB-C (cable) and 2.6 GHz band mobile broadcasting which are all based on MPEG-2, MPEG-4, or HEVC standard for multiplexing with transport stream structure and video and audio coding (MPEG-2, H.264, or HEVC) and are capable of UHD, high-definition television (HDTV) and standard-definition television. ISDB-T and ISDB-Tsb are for mobile reception in TV bands. 1seg is the name of an ISDB-T component that allows viewers to watch TV channels via cell phones, laptop computers, and vehicles.
The concept was named for its similarity to ISDN as both allow multiple channels of data to be transmitted together (a process called multiplexing). This broadcast standard is also much like another digital radio system, Eureka 147, which calls each group of stations on a transmitter an ensemble; this is very much like the multi-channel digital TV standard DVB-T. ISDB-T operates on unused TV channels, an approach that was taken by other countries for TV but never before for radio.
ISDB-S
Japan started digital broadcasting using the DVB-S standard by PerfecTV in October/1996, and DirecTV in December/1997, with communication satellites. Still, DVB-S did not satisfy the requirements of Japanese broadcasters, such as NHK, key commercial broadcasting stations like Nippon Television, TBS, Fuji Television, TV Asahi, TV Tokyo, and WOWOW (Movie-only Pay-TV broadcasting). Consequently, ARIB developed a new broadcast standard called ISDB-S. The requirements were HDTV capability, interactive services, network access and effective frequency utilization, and other technical requirements. The DVB-S standard allows the transmission of a bitstream of roughly 34 Mbit/s with a satellite transponder, which means the transponder can send one HDTV channel. Unfortunately, the NHK broadcasting satellite had only four vacant transponders, which led ARIB and NHK to work on ISDB-S: the new standard could transmit at 51 Mbit/s with a single transponder, which means that ISDB-S is 1.5 times more efficient than DVB-S and that one transponder can transmit two HDTV channels, along with other independent audio and data. Digital satellite broadcasting (BS digital) was started by NHK and followed commercial broadcasting stations on 1 December 2000. Today, SKY PerfecTV! (the successor of Skyport TV and Sky D), CS burn, Platone, EP, DirecTV, J Sky B, and PerfecTV!, adopted the ISDB-S system for use on the 110-degree (east longitude) wide-band communication satellite.
*ISDB-S3 is a satellite digital broadcasting specification for 4K/8K (UHDTV) satellite broadcasting in Japan.
ISDB-S3 is a satellite digital broadcasting specification supporting 4K, 8K, HDR, HFR, and 22.2 audio.
ISDB-C
ISDB-C is a cable digital broadcasting specification. The technical specification J.83/C is developed by JCTEA. ISDB-C is identical to DVB-C but has a different channel bandwidth of 6 MHz (instead of 8 MHz) and roll-off factor.
ISDB-T
HDTV was invented at NHK Science & Technology Research Laboratories (Japan Broadcasting Corporation's Science & Technical Research Laboratories). The research for HDTV started as early as the 1960s, though a standard was proposed to the ITU-R (CCIR) only in 1973.
By the 1980s, a high definition television camera, cathode-ray tube, videotape recorder, and editing equipment, among others, had been developed. In 1982 NHK developed MUSE (Multiple sub-Nyquist sampling encoding), the first HDTV video compression and transmission system. MUSE used digital video compression, but for transmission frequency modulation was used after a digital-to-analog converter converted the digital signal.
In 1987, NHK demonstrated MUSE in Washington D.C. as well as NAB. The demonstration made a great impression in the U.S., leading to the development of the ATSC terrestrial DTV system. Europe also developed a DTV system called DVB. Japan began R&D of a completely digital system in the 1980s that led to ISDB. Japan began terrestrial digital broadcasting, using ISDB-T standard by NHK and commercial broadcasting stations, on 1 December 2003.
Adoption
ISDB-T was adopted for commercial transmissions in Japan in December 2003. It currently comprises a market of about 100 million television sets. ISDB-T had 10 million subscribers by the end of April 2005. Along with the wide use of ISDB-T, the price of receivers is getting low. The price of ISDB-T STB in the lower end of the market is ¥19800 as of 19 April 2006.[27] By November 2007 only a few older, low-end STB models could be found in the Japanese market (average price U$180), showing a tendency towards replacement by mid to high-end equipment like PVRs and TV sets with inbuilt tuners. In November 2009, a retail chain AEON introduced STB in 40 USD,[28] followed by variety of low-cost tuners. The Dibeg web page confirms this tendency by showing low significance of the digital tuner STB market in Japan.
Brazil, which used an analogue TV system (PAL-M) that slightly differed from any other countries, has chosen ISDB-T as a base for its DTV format, calling it ISDB-Tb or internally SBTVD (Sistema Brasileiro de Televisão Digital-Terrestre). The Japanese DiBEG group incorporated the advancements made by Brazil -MPEG4 video codec instead of ISDB-T's MPEG2 and a powerful interaction middleware called Ginga- and has renamed the standard to "ISDB-T International".[30] Other than Argentina, Brazil, Peru, Chile and Ecuador[31] which have selected ISDB-Tb, there are other South American countries, mainly from Mercosur, such as Venezuela,[32] that chose ISDB-Tb, which providing economies of scale and common market benefits from the regional South American manufacturing instead of importing ready-made STBs as is the case with the other standards. Also, it has been confirmed with extensive tests realized by Brazilian Association of Radio and Television Broadcasters (ABERT), Brazilian Television Engineering Society (SET) and Universidade Presbiteriana Mackenzie the insufficient quality for indoor reception presented by ATSC and, between DVB-T and ISDB-T, the latter presented superior performance in indoor reception and flexibility to access digital services and TV programs through non-mobile, mobile or portable receivers with impressive quality.[33]
The ABERT–SET group in Brazil did system comparison tests of DTV under the supervision of the CPqD foundation. The comparison tests were done under the direction of a work group of SET and ABERT. The ABERT/SET group selected ISDB-T as the best choice in digital broadcasting modulation systems among ATSC, DVB-T and ISDB-T.[citation needed] Another study found that ISDB-T and DVB-T performed similarly, and that both were outperformed by DVB-T2.[34]
ISDB-T was singled out as the most flexible of all for meeting the needs of mobility and portability. It is most efficient for mobile and portable reception. On June 29, 2006, Brazil announced ISDB-T-based SBTVD as the chosen standard for digital TV transmissions, to be fully implemented by 2016. By November 2007 (one month prior DTTV launch), a few suppliers started to announce zapper STBs of the new Nippon-Brazilian SBTVD-T standard, at that time without interactivity.
As in 2019, the implementation rollout in Brazil proceeded successfully, with terrestrial analog services (PAL-M) phased out in most of the country (for some less populated regions, analog signal shutdown was postponed to 2023).
Adoption by country
On February 26, 2013, the Botswana government adopts the ISDB-T standard; as the first country within the SADC region and even the first country within the continent of Africa as a whole.
On September 12, 2013, Honduras adopted the ISDB-T standard.
On May 20, 2014, Government of Sri Lanka officially announced its decision to adopt ISDB-T standard,[45] and on September 7, 2014 Japanese Prime Minister Shinzo Abe signed an agreement with Sri Lankan President Mahinda Rajapakse for constructing infrastructure such as ISDB-T networks with a view to smooth conversion to ISDB-T, and cooperating in the field of content and developing human resources.
On January 23, 2017, El Salvador adopted the ISDB-T standard.
On March 20, 2019, Angola adopted the ISDB-T standard.
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