is a mobile terrestrial digital audio/video and data broadcasting service in Japan,

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

Paraguay Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

and the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. Service began experimentally during 2005 and commercially on April 1, 2006. It is designed as a component of ISDB-T, the terrestrial digital broadcast system used in those countries, as each channel is divided into 13 segments, with a further segment separating it from the next channel; an

HDTV High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the ...

broadcast signal occupies 12 segments, leaving the remaining (13th) segment for mobile receivers, hence the name, "1seg" or "One Seg". Its use in Brazil was established in late 2007 (starting in just a few cities), with a slight difference from the Japanese counterpart: it is broadcast under a 30 frame/s transmission setting (Japanese broadcasts are under the 15 frame/s transmission setting).

Technical information

The

ISDB Integrated Services Digital Broadcasting (ISDB; Japanese: , ''Tōgō dejitaru hōsō sābisu'') is a Japanese broadcasting standard for digital television (DTV) and digital radio. ISDB supersedes both the NTSC-J analog television system and ...

-T system uses the

UHF Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (on ...

band at frequencies between 470 and 770 MHz (806 MHz in Brazil), giving a total bandwidth 300 MHz. The bandwidth is divided into fifty name channels 13 through 62. Each channel is 6 MHz wide consisting of a 5.57 MHz wide signalling band and a 430 kHz guard band to limit cross channel interference. Each of these channels is further divided into 13 segments, each with 428 kHz of bandwidth. 1 seg uses a single of these segments to carry the 1seg transport stream. 1seg, like ISDB-T uses

QPSK Phase-shift keying (PSK) is a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency reference signal (the carrier wave). The modulation is accomplished by varying the sine and cosine inputs at ...

for

modulation In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the '' carrier signal'', with a separate signal called the ''modulation signal'' that typically contains informat ...

, with 2/3

forward error correction In computing, telecommunication, information theory, and coding theory, an error correction code, sometimes error correcting code, (ECC) is used for controlling errors in data over unreliable or noisy communication channels. The central idea is ...

and 1/4 guard ratio. The total datarate is 416 kbit/s. The television system uses an H.264/MPEG-4 AVC video stream and an

HE-AAC High-Efficiency Advanced Audio Coding (HE-AAC) is an audio coding format for lossy data compression of digital audio defined as an MPEG-4 Audio profile in ISO/ IEC 14496–3. It is an extension of Low Complexity AAC (AAC-LC) optimized f ...

audio stream multiplexed into an

MPEG transport stream MPEG transport stream (MPEG-TS, MTS) or simply transport stream (TS) is a standard digital container format for transmission and storage of audio, video, and Program and System Information Protocol (PSIP) data. It is used in broadcast syste ...

. The maximum video resolution is 320x240 pixels, with a video bitrate of between 220 and 320 kbit/s. Audio conforms to

profile, with a bitrate of 48 to 64 kbit/s. Additional data ( EPG, interactive services, etc.) is transmitted using BML and occupies the remaining 10 to 100 kbit/s of bandwidth. Conditional access and copy control are implemented in 1seg broadcasting by the use of Broadcast Flag-like structure contained in the "Copy Control Descriptor" within the broadcast. The broadcast contents themselves are not encrypted, but the Copy Control information forces the device to encrypt stored recordings and disallows making a copy of the recording.

Broadcast Markup Language

Broadcast Markup Language Broadcast Markup Language, or BML, is an XML-based standard developed by Japan's Association of Radio Industries and Businesses as a data broadcasting specification for digital television broadcasting. It is a data-transmission service allowing ...

(BML), is a data-transmission service allowing text to be displayed on a 1seg TV screen. The text contains news, sports, weather forecasts, emergency warnings such as

Earthquake Early Warning An earthquake warning system or earthquake early warning system is a system of accelerometers, seismometers, communication, computers, and alarms that is devised for notifying adjoining regions of a substantial earthquake while it is in progr ...

, etc. free of charge. Further information can be found through links to content on websites, frequently those belonging to the television station itself. EPG (program guides) is not included, but transmitted in separate stream (EIT).

Multiple-program arrangement

On June 23, 2008, broadcaster

Tokyo MX JOMX-DTV, branded as Tokyo MX (officially stylized as TOKYO MX), is an independent television station in Tokyo, Japan, owned by the . It is the only television station that exclusively serves the city. It competes with Nippon TV, TV Asahi, NH ...

officially began using technology to simultaneously broadcast two programs on a single divided segment. Most 1seg receivers manufactured after September 2008 are compatible with this technology. Multiple-program arrangement in 1seg is named as .

NHK Educational TV , abbreviated on-screen as NHK E, is the second television service of NHK (Japan Broadcasting Corporation). It is a sister service of NHK General TV, showing programs of a more educational, cultural or intellectual nature, periodically also s ...

(from 1 April 2009) and (from 1 December 2009) are also started for several number of programs.

Popularity

Until the end of March 2008, Japanese regulation required that the programs on 1seg were fundamentally the same as those broadcast on the equivalent HDTV channel. On April 1 the regulation was revised, and experimental programs by 1seg or third parties have begun airing on several stations. On January 16, 2008, JEITA released their monthly shipping survey showing approx. 4.806 million

mobile phone A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive telephone call, calls over a radio freq ...

s were sold in Japan in November 2007. Of these, approx. 3.054 million phones, 63.5% of the total, can receive 1seg broadcasts. In the fiscal year of 2007, on average 45% of mobile phones had 1seg reception capability out of the 22.284 million units sold. The percent increased from 26.8% in April 2007 to 64.2% at end of fiscal year March 2008.2007年度移動電話国内出荷実績
(2007 fiscal year mobile phone ship out record) (In Japanese)

Receivers

; Electronic dictionary : Sharp Papyrus PW-TC900 : Sharp Papyrus PW-TC920 : Sharp Papyrus PW-TC930 : Sharp Papyrus PW-TC980 ;PC connect type : Pixela PC : Monster TV 1D PC card Type II 1seg receiver by SKNET : Cowon D2TV : and more. ;

Car navigation system An automotive navigation system is part of the automobile controls or a third party add-on used to find direction in an automobile. It typically uses a satellite navigation device to get its position data which is then correlated to a position on ...

: Sanyo One-seg & car navigation system : and more. ;

Handheld game console A handheld game console, or simply handheld console, is a small, portable self-contained video game console with a built-in screen, game controls and speakers. Handheld game consoles are smaller than home video game consoles and contain the cons ...

:
1seg PSP-2000 Tuner
: Nintendo DS (via an add-on called "DS Terebi") ;

Portable devices A mobile device (or handheld computer) is a computer small enough to hold and operate in the hand. Mobile devices typically have a flat LCD or OLED screen, a touchscreen interface, and digital or physical buttons. They may also have a physical k ...

; Set top box ;Others :

Sony , commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...

Walkman NW-A919 :

Kodak The Eastman Kodak Company (referred to simply as Kodak ) is an American public company that produces various products related to its historic basis in analogue photography. The company is headquartered in Rochester, New York, and is incorpor ...

3-inch OLED TV : and more. ; Mobile Phones :The first mobile phone handsets able to support 1seg were sold by au by KDDI to consumers in autumn 2005. Today, almost all mobile phones sold in Japan feature a 1seg antenna (only for and

Android Android may refer to: Science and technology * Android (robot), a humanoid robot or synthetic organism designed to imitate a human * Android (operating system), Google's mobile operating system ** Bugdroid, a Google mascot sometimes referred to ...

smartphones sold by carriers, iOS users must purchase a third-party 1seg antenna separately).

References

External links

*
ISDB-T, Application, Present and Future
PDF File *
1seg official site (Japanese)

ACCESS Ginga Edition for 1Seg in BrazilGPS fitted with ISDB-T OneSeg sales grow in Brazil
{{DEFAULTSORT:1seg ISDB Broadcast engineering Digital television Mobile telephone broadcasting Mobile television Television transmission standards