Patent ID: 7822135

Claim:
A multiple-input-multiple output (MIMO) transmitter for transmitting an orthogonal frequency division multiplexed (OFDM) symbol over a plurality of spatial channels using a plurality of antennas comprising: encoding circuitry to encode blocks of input bits in accordance with a variable encoding rate to generate blocks of encoded bits; a spatial-frequency parser to parse the blocks of encoded bits into spatial-frequency groups; subcarrier modulators to modulate each spatial-frequency group of encoded bits on one of the OFDM subcarriers to generate symbol-modulated subcarriers, wherein spatial-frequency groups having a greater number of encoded bits are modulated at higher-order modulation levels and spatial-frequency groups having a lesser number of encoded bits are modulated at lower-order modulation orders; and circuitry to combine the symbol-modulated subcarriers and generate signals for transmission through each of the spatial channels, the spatial channels being non-orthogonal and having different multipath characteristics, wherein the spatial-frequency subcarrier modulation assignments are determined from channel characteristics of the subcarriers for the spatial channels.