Terrestrial digital television broadcasting system is not only suitable for receiving buses and mobile vehicles in urban areas, but also covers towns and villages, realizing the main transmission means of "village and village" radio and television. It is of far-reaching significance to build a terrestrial digital television broadcasting system that meets the standards.

Make up

It consists of studio, transmitter tower, high-power transmitter, TV relay car and so on.

layout

The studio is the center of the system. High-power transmitters and towers are often installed on taller buildings or terrains.

Video and audio coding and compression standards

In the terrestrial digital television broadcasting test system, select what kind of video and audio coding and compression standard, according to the selected video and audio coding and compression standard, the video and audio signal source and auxiliary data are compressed and encoded. The selection of video and audio coding and compression standards is more limited because of the poor mobile reception conditions of terrestrial digital television broadcasting. In the case of good coverage, the compression method of MPEG-2 can only transmit one real-time digital TV program, and the compression method of higher compression rate such as MPEG-4 can realize the transmission of multi-channel programs in a TV channel, and complete the terrestrial broadcasting and mobile reception of multiple sets of digital TV programs. The video and audio coding and compression standards of the front-end system can adopt MPEG-2 or MPEG-4, but other standards such as AvS and H264 are not excluded.

Front-end function

Edit and produce video and audio programs to form broadcast video and audio program sources. The front end is mainly composed of non-line '! Raw editing system, broadcast control software, MPEG-2 (or MPEG-4) video and audio encoder, digital video and audio stream server, stream generator, data protocol processor and data baler, program level stream multiplexer, system level stream multiplexer, single frequency network adapter, GPS(Global Positioning System) synchronous clock source, etc.