The invention provides a downlink
transmitter system and an operating method thereof. The downlink
transmitter system is used for supporting transmission of two-
channel code words in a double-antenna channel and comprises a
processing module, a layer mapping module, a
precoding module and a resource mapping module, wherein the
processing module is used for subjecting the inputted two-
channel code words to time-sharing serial
processing in a one-
channel code word direction so as to obtain a
code word serial data flow; the layer mapping module is used for subjecting the
code word serial data flow to layering processing and outputting two
layers of data flows; the
precoding module is used for preprocessing the two
layers of data flows and distributing the two
layers of preprocessed data flows to different antenna ports; the resource mapping module is used for storing, reading and adding the two layers of data flows. The downlink
transmitter system has the advantages of low hardware cost, simplicity in control, high universality and
extensibility, capability of supporting downlink channel transmission and multiple double-antenna transmission
modes stipulated by protocols and compatibility with single-antenna transmission
modes.