In the field of telecommunications, data link is a means of connecting one location to another for the transmission and reception of digital information. It can also refer to a set of electronic components, including transmitter and receiver (two data terminal devices) and interconnected data telecommunication circuits. These data are managed by link protocol, which enables digital data to be transmitted from data source to data receiver. Data chain is a ground space, space space, ground ground tactical wireless data communication system which transmits formatted digital information in real time in a bit oriented way by using modulation and demodulation, coding and decoding, anti-interference, networking communication and information fusion technology according to the specified information format and communication protocol. The basic components of data chain can be summarized into three main elements: terminal equipment, transmission equipment and communication specification.
The functions of data chain include map transmission, data transmission, networking, air to ground video transmission, air-to-ground bidirectional data transmission, UAV, remote control and telemetry of aircraft, UAV air network, UAV Communication Relay, etc. The application fields of data chain include various multi rotor aircraft, fixed wing UAV, unmanned helicopter, missile, guided shell, etc.