Digital terrestrial television in the context of "Xbox One"

Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. In the 2000s it was represented as the first significant evolution in television technology since color television in the 1950s. Modern digital television is transmitted in high-definition television (HDTV) with greater resolution than analog TV. It typically uses a widescreen aspect ratio (commonly 16:9) in contrast to the narrower format (4:3) of analog TV. It makes more economical use of scarce radio spectrum space; it can transmit up to seven channels in the same bandwidth as a single analog channel, and provides many new features that analog television cannot. A transition from analog to digital broadcasting began around 2000. Different digital television broadcasting standards have been adopted in different parts of the world; below are the more widely used standards:

• Digital Video Broadcasting (DVB) uses coded orthogonal frequency-division multiplexing (OFDM) modulation and supports hierarchical transmission. This standard has been adopted in Europe, Africa, Asia and Australia, for a total of approximately 60 countries.
• Advanced Television System Committee (ATSC) standard uses eight-level vestigial sideband (8VSB) for terrestrial broadcasting. This standard has been adopted by 9 countries: the United States, Canada, Mexico, South Korea, Bahamas, Jamaica, the Dominican Republic, Haiti and Suriname.
• Integrated Services Digital Broadcasting (ISDB) is a system designed to provide good reception to fixed receivers and also portable or mobile receivers utilizing OFDM and two-dimensional interleaving. It supports hierarchical transmission of up to three layers and uses MPEG-2 video and Advanced Audio Coding. This standard has been adopted in Japan and the Philippines. ISDB-T International is an adaptation of this standard using H.264/MPEG-4 AVC, which has been adopted in most of South America as well as Botswana and Angola. 1seg (1-segment) is a special form of ISDB. Each channel is further divided into 13 segments. Twelve are allocated for HDTV and the other for narrow-band receivers such as mobile televisions and cell phones.
• Digital Terrestrial Multimedia Broadcast (DTMB) adopts time-domain synchronous (TDS) OFDM technology with a pseudo-random signal frame to serve as the guard interval (GI) of the OFDM block and the training symbol. The DTMB standard has been adopted in China, including Hong Kong and Macau.
• Digital Multimedia Broadcasting (DMB) is a digital radio transmission technology developed and adopted in South Korea as part of the national information technology project for sending multimedia such as TV, radio and datacasting to mobile devices such as mobile phones, laptops and GPS navigation systems.

Tokyo Skytree (東京スカイツリー, Tōkyō Sukaitsurī; [toːkʲoː sɯ̥kaitsɯriː] ), also written as Tokyo Sky Tree, is a broadcasting and observation tower, located in Sumida, Tokyo, Japan. It has been the tallest tower in Japan since opening in 2012, and reached its full height of 634 m (2,080 ft) in early 2011, making it the tallest tower in the world, displacing the Canton Tower, and the third tallest structure in the world behind Merdeka 118 (678.9 m or 2,227 ft) and Burj Khalifa (829.8 m or 2,722 ft).

The tower is the primary television and radio broadcast site for the Kantō region; the older Tokyo Tower no longer gives complete digital terrestrial television broadcasting coverage because it is surrounded by high-rise buildings. Skytree was completed on Leap Day, 29 February 2012, with the tower opening to the public on 22 May 2012. The tower is the centerpiece of a large commercial development funded by Tobu Railway (which owns the complex) and a group of six terrestrial broadcasters headed by NHK. Trains stop at the adjacent Tokyo Skytree Station and nearby Oshiage Station. The complex is 7 km (4.3 mi) northeast of Tokyo Station. Sumida Aquarium is in the Tokyo Solamachi complex.

A television channel, or TV channel, is a terrestrial frequency or allocated number over which a television station or television network is distributed. For example, in North America, channel 2 refers to the terrestrial or cable band of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video (VSB) and 59.75 MHz for analog audio (FM), or 55.31 MHz for digital ATSC (8VSB). Channels may be shared by many different television stations or cable-distributed channels depending on the location and service provider.

Depending on the multinational bandplan for a given region, analog television channels are typically 6, 7, or 8 MHz in bandwidth, and therefore television channel frequencies vary as well. Channel numbering is also different. Digital terrestrial television channels are the same as their analog predecessors for legacy reasons, however through multiplexing, each physical radio frequency (RF) channel can carry several digital subchannels. On satellites, each transponder normally carries one channel, however multiple small, independent channels can be on one transponder, with some loss of bandwidth due to the need for guard bands between unrelated transmissions. ISDB, used in Japan and Brazil, has a similar segmented mode.

A set-top box (STB), also known as a cable box, receiver, or simply box, and historically television decoder or a converter, is an information appliance device that generally contains a TV tuner input and displays output to a television set, turning the source signal into content in a form that can then be displayed on the television screen or other display device. It is designed to be placed alongside or "on top" (hence the name) of a television set.

Set-top boxes are used in cable television, satellite television, terrestrial television and Internet Protocol television systems, as well as other uses such as digital media players ("streaming boxes"). Alternatives to set-top boxes are the smaller dongles, and television sets with built-in TV tuners.

Pay television, also known as subscription television, premium television or, when referring to an individual service, a premium channel, refers to subscription-based television services, usually provided by multichannel television providers, but also increasingly via digital terrestrial and streaming television. In the United States, subscription television began in the late 1970s and early 1980s in the form of encrypted analog over-the-air broadcast television which could be decrypted with special equipment. The concept rapidly expanded through the multi-channel transition and into the post-network era. Other parts of the world beyond the United States, such as France and Latin America have also offered encrypted analog terrestrial signals available for subscription.

The term is most synonymous with premium entertainment services focused on films or general entertainment programming such as, in the United States, Cinemax, HBO, MGM+, Showtime, and Starz, but such services can also include those devoted to sports, as well as adult entertainment.

Television in Japan was introduced in 1939. However, experiments date back to the 1920s, with Kenjiro Takayanagi's pioneering experiments in electronic television. Television broadcasting was halted by World War II, after which regular television broadcasting began in 1950. After Japan developed the first HDTV systems in the 1960s, MUSE/Hi-Vision was introduced in the 1970s.

A modified version of the NTSC system for analog signals, called NTSC-J, was used for analog broadcast between 1950 and the early 2010s. The analog broadcast in Japan was replaced with a digital broadcasts using the ISDB standard. ISDB supersedes both the NTSC-J analog television system and the previously used MUSE Hi-vision analog HDTV system in Japan. Digital Terrestrial Television Broadcasting (DTTB) services using ISDB-T (ISDB-T International) started in Japan in December 2003, and since then, Japan adopted ISDB over other digital broadcasting standards.

The digital television transition, also called the digital switchover (DSO), the analogue switch/sign-off (ASO), the digital migration, or the analogue shutdown, is the process in which older analogue television broadcasting technology is converted to and replaced by digital television. Conducted by individual nations on different schedules, this primarily involves the conversion of analogue terrestrial television broadcasting infrastructure to Digital terrestrial television (DTT), a major benefit being extra frequencies on the radio spectrum and lower broadcasting costs, as well as improved viewing qualities for consumers.

The transition may also involve analogue cable conversion to digital cable or Internet Protocol television, as well as analogue to digital satellite television. Transition of land based broadcasting had begun in some countries around 2000. By contrast, transition of satellite television systems was well underway or completed in many countries by this time. It is an involved process because the existing analogue television receivers owned by viewers cannot receive digital broadcasts; viewers must either purchase new digital TVs, or digital converter boxes which have a digital tuner and change the digital signal to an analogue signal or some other form of a digital signal (i.e. HDMI) which can be received on the older TV. Usually during a transition, a simulcast service is operated where a broadcast is made available to viewers in both analogue and digital at the same time. As digital becomes more popular, it is expected that the existing analogue services will be removed. In most places this has already happened, where a broadcaster has offered incentives to viewers to encourage them to switch to digital. Government intervention usually involves providing some funding for broadcasters and, in some cases, monetary relief to viewers, to enable a switchover to happen by a given deadline. In addition, governments can also have a say with the broadcasters as to what digital standard to adopt – either DVB-T2 ATSC Governments can also require all receiving equipment sold in a country to support the necessary digital 'tuner'.

Advanced Television Systems Committee (ATSC) standards are an international set of standards for broadcast and digital television transmission over terrestrial, cable and satellite networks. It is largely a replacement for the analog NTSC standard. Like NTSC, ATSC is used mostly in the United States, Mexico, Canada, South Korea, and Trinidad and Tobago. Several former NTSC users like Japan have not used ATSC during their digital television transition, because they adopted other systems like ISDB developed by Japan and DVB developed in Europe, for example.

The ATSC standards were developed in the early 1990s by the Grand Alliance, a consortium of electronics and telecommunications companies that assembled to develop a specification for what is now known as HDTV. The standard is now administered by the Advanced Television Systems Committee. It includes a number of patented elements, and licensing is required for devices that use these parts of the standard. Key among these is the 8VSB modulation system used for over-the-air broadcasts. ATSC 1.0 technology was primarily developed with patent contributions from LG Electronics, which held most of the patents for the ATSC standard.