The present disclosure relates to embodiments of a precoding method and systems for implementing those embodiments. The embodiments includes receiving, by a level 2 data center, level 1 channel information sent by at least two level 1 data centers, where the level 1 channel information includes a channel matrix between a terminal and the level 1 data center; performing, by the level 2 data center, calculation according to the channel matrix, to obtain a level 2 precoding matrix; and generating, by the level 2 data center, a level 2 signal according to a signal sent to the terminal and the level 2 precoding matrix, and sending the level 2 signal to the level 1 data center. The level 2 data center generates the level 2 signal according to the signal sent to the terminal and the level 2 precoding matrix.