Pre-coding method, device and system

Provided in an embodiment of the present invention are a pre-coding method, device and system, the method comprising: with respect to each sub-carrier, acquiring a channel matrix on the sub-carriers, the channel matrix consisting of channel vectors of all users on the sub-carriers, and the users comprising linear users supporting linear pre-coding and non-linear users supporting non-linear pre-coding; calculating to obtain a pre-coding matrix according to the channel matrix; conducting, according to the channel matrix, non-linear pre-coding on a signal to be transmitted to the non-linear users; and conducting linear pre-coding on the transmitted signal according to the pre-coding matrix, the transmitted signal comprising a signal to be transmitted to the linear users and a signal to be transmitted to the non-linear users and already having the non-linear pre-coding. The embodiment of the present invention maintains speeds of the linear users and non-linear users thereby realizing a win-win scenario, reduces error rates and improves the stability of a system.