1seg

1seg (ワンセグ, wansegu) is a mobile terrestrial digital audio/video and data broadcasting service in Japan, Argentina, Brazil, Chile, Uruguay, Paraguay, Peru and the Philippines. 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 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 fps transmission setting (Japanese broadcasts are under the 15 fps transmission setting). By 2014, approximately 62% of Brazil's population was covered by digital TV signals carrying 1seg, with the government targeting full national coverage by 2016. The standard, adopted regionally as ISDB-Tb, was also implemented in Argentina, Peru, Chile, Ecuador, Venezuela, Bolivia, and Paraguay following Brazil's lead, alongside the Philippines, which adopted the closely related ISDB-T International variant.