Patent ID: 7970074

Claim:
A method for transmitting signals at a transmitter of a Multi-Input Multi-Output (MIMO) system using a plurality of antennas, the method comprising: encoding input signals of an encoder to output one or more streams; performing a precoding on the one or more streams at a precoder to map the one or more streams to the plurality of antennas using a specific precoding matrix selected from a first codebook, wherein the first codebook includes (N restrict ) precoding matrices, wherein each of the (N restrict ) precoding matrices has an index (i), (i)=0, 1, . . . , (N restrict )−1, wherein the specific precoding matrix is selected according to (i)=(s) mod (N restrict ), wherein ‘mod’ indicates a modulo operation, wherein (s) is a variable which changes every (v) contiguous subcarriers, and (v) is a predetermined integer value; and transmitting the antenna-mapped signals to a receiver.