Patent ID: 7948960
Filing Date: 2011-05-24
Classification: H04B,H04L

Abstract:
1. A radio transmitter having a plurality of transmitting antennas for transmitting a transmission signal in units of sub-carriers by performing spatial multiplexing or without performing spatial multiplexing, comprising: a sub-carrier modulation part modulating an input transmission signal for each sub-carrier; a transmission signal allocation part allocating said transmission signal modulated for each of sub-carriers to each of said transmitting antennas; and a transmission control part that determines whether to perform spatial multiplexing for the sub-carriers based on information received from another radio communication device as a destination communication apparatus, and when performing spatial multiplexing for each of said sub-carriers, said transmission control part determines a spatial multiplexing number for performing spatial multiplexing for each of said sub-carriers and outputs said determined spatial multiplexing number to said sub-carrier modulation part and said transmission signal allocation part, when performing spatial multiplexing for sub-carriers grouped in block units where signal processing of said transmission signal is performed in said block units, said transmission control part determines a spatial multiplexing number for performing spatial multiplexing for each block unit of sub-carriers, wherein the same multiplexing number is assumed for each sub-carrier in a block unit, while when not performing spatial multiplexing, said transmission control part outputs the same signal to said transmission allocation part, wherein the radio transmitter transmits the signal by performing spatial multiplexing with the spatial multiplexing number selected for each of said sub-carriers, transmits a different signal by each block unit of sub-carriers by performing spatial multiplexing for each block unit with the spatial multiplexing number determined for each block unit, respectively, or transmits the same signal by each antenna.