MIMO OFDM with ST Coding and Beamforming Adapted to Partial CSI
نویسندگان
چکیده
We study adaptive multi-input multi-output (MIMO) space-time (ST) OFDM transmissions capable of adapting to partial channel state information (CSI) that is available at the transmitter. Our proposed transmitter includes an outer stage (adaptive modulation), and an inner stage (adaptive beamforming). Specifically, the inner stage switches between a onedimensional (1D) and a balanced two-dimensional (B2D) coderbeamformer, whereas the outer stage carries out joint power and bit loading across OFDM subcarriers. The adaptive transmitter based on 1D/B2D beamformer switching performs close to its counterpart based on a general 2D beamformer structure, while obviating the need for numerical search when carrying out the power splitting between two basis beams.
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