The invention discloses a multi-carrier communication method and device of a TDD mode 
MIMO wireless communication 
system. The 
wireless communication 
system has a plurality of channels of base band signals, and each channel of signals include two spatial flow signals; the method includes the steps that 
frequency conversion is carried out by a 
transmitter on the multi-channel two-spatial-flow base band signals two times to obtain different-frequency single carrier 
microwave frequency band signals of the multi-channel two-spatial-flow, then the different-frequency single carrier 
microwave frequency band signals are merged to form a single channel of 
cross polarization double-spatial-flow multi-carrier 
microwave frequency band signals to be transmitted through a single antenna, the single channel of 
cross polarization double-spatial-flow multi-carrier 
microwave frequency band signals are separated by a 
receiver into multiple-channel two-spatial-flow single carrier 
microwave frequency band signals, and down-conversion is carried out on the multiple-channel two-spatial-flow single carrier 
microwave frequency band signals two times to obtain the multiple channels of base band signals. The invention further provides the multi-carrier 
communication device of the TDD mode 
MIMO wireless communication 
system in the mode. Compared with the prior art, the multi-carrier communication method and device have the advantages that abundant spectrum resources of 
millimeter waves can be effectively utilized, and the 
data transmission handling capacity of the wireless communication system can be improved in a multiplied mode.