A TV channel is a branch of a physical or virtual channel in a TV station or TV network. For example, in North America, "Channel 2" refers to broadcast or cable 54-60 MHz band, carrier frequency NTSC analog video (vestigial sideband) and 59.75 MHz analog audio (FM), or 55.35438+0 MHz ATSC standard number. Channels can enjoy location and service provider channels distributed by many different TV stations or cable TV.
According to the transnational band planning of a certain region, analog TV channels usually have a bandwidth of 6, 7 or 8MHz, so the frequencies of TV channels are different. The channel numbers are also different. Digital TV channels are for traditional reasons, but also through multiplexing, each physical radio frequency (RF) channel can carry out several digital subchannels. With regard to satellites, each transponder usually has one channel. No matter how small, each repeater can use an independent channel. Due to the transmission bandwidth, the frequency bands between defenders need ISDB, which is used in Japan and Brazil, and there is a similar division method.