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

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

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, th ...

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 east a ...

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 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 th ...

, 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 g ...

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 language, Japanese: , ''Tōgō dejitaru hōsō sābisu'') is a Japanese broadcasting standard for digital television (DTV) and digital radio. ISDB supersedes both the NTSC-J analog telev ...

-T system uses the UHF 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 a ...

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 informatio ...

, 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 for lo ...

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 systems ...

. 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 Electronic programming guides (EPGs) and interactive programming guides (IPGs) are menu-based systems that provide users of television, radio and other media applications with continuously updated menus that display scheduling information for ...

, 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 A broadcast flag is a bit field sent in the data stream of a digital television program that indicates whether or not the data stream can be recorded, or if there are any restrictions on recorded content. Possible restrictions include the inabili ...

-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 tex ...

(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 progress ...

, etc. free of charge. Further information can be found through links to content on websites, frequently those belonging to the television station itself.

(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 sh ...

(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 The is a Japanese trade organization for the electronics and IT industries. It was formed in 2000 from two earlier organizations, the Electronic Industries Association of Japan and the Japan Electronic Industries Development Association. Histor ...

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 calls over a radio frequency link whil ...

s were sold in

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 An electronic dictionary is a dictionary whose data exists in digital form and can be accessed through a number of different media. Electronic dictionaries can be found in several forms, including software installed on tablet or desktop computers ...

: 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 In computing, PC Card is a configuration for computer parallel communication peripheral interface, designed for laptop computers. Originally introduced as PCMCIA, the PC Card standard as well as its successors like CardBus were defined and devel ...

Type II 1seg receiver by SKNET :

Cowon Cowon Systems, Inc. (simply known as Cowon) is a South Korean consumer electronics and software corporation. The company’s initial focus was software development and microelectronics, specializing in speech synthesis and speech recognition te ...

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 The is a handheld game console produced by Nintendo, released globally across 2004 and 2005. The DS, an initialism for "Developers' System" or "Dual Screen", introduced distinctive new features to handheld games: two LCD screens working in tan ...

(via an add-on called "DS Terebi") ; Portable devices ;

Set top box A set-top box (STB), also colloquially known as a cable box and historically television decoder, is an information appliance device that generally contains a TV-tuner input and displays output to a television set and an external source of si ...

;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 Walkman, stylised as , is a brand of portable audio players manufactured and marketed by Japanese technology company Sony since 1979. The original Walkman was a portable cassette player and its popularity made "walkman" an unofficial term for ...

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 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 calls over a radio frequency link whil ...

:The first mobile phone handsets able to support 1seg were sold by

au by KDDI au, or au by KDDI, is a Japanese mobile phone operator. au is a brand marketed by KDDI in the main islands of Japan and by Okinawa Cellular in Okinawa for their mobile cellular services. au is the second-largest wireless carrier in Japan, wit ...

to consumers in autumn 2005. Today, almost all mobile phones sold in Japan feature a 1seg antenna (only for and Android smartphones sold by carriers,

iOS iOS (formerly iPhone OS) is a mobile operating system created and developed by Apple Inc. exclusively for its hardware. It is the operating system that powers many of the company's mobile devices, including the iPhone; the term also includes ...

users must purchase a third-party 1seg antenna separately).

References

External links

*
ISDB-T, Application, Present and Future

PDF Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. ...

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