DATA TRANSMISSION METHOD, DEVICE AND SYSTEM

The present invention relates to the field of communications technologies, and discloses a data transmission method, a device, and a system, to resolve a prior-art problem that a transmission quality target cannot meet a requirement of a low-delay and high-reliability service and a system efficiency requirement at the same time. A specific solution is as follows: A first communications device obtains a first transmission quality target and first channel quality information, determines a modulation and coding scheme MCS of to-be-transmitted data based on the first transmission quality target and the first channel quality information, codes and modulates the to-be-transmitted data based on the MCS of the to-be-transmitted data, and sends the MCS of the to-be-transmitted data and the coded and modulated to-be-transmitted data to a second communications device. The present invention is applied to data transmission.