Transmitter Precoding for Orthogonal Space-Time Block-Coded OFDM in Transmit-Antenna and Path-Correlated Channels
Orthogonal Space-Time Block-Coded (OSTBC) Orthogonal Frequency-Division Multiplexing (OFDM) links for frequency-selective Multiple-Input Multiple-Output (MIMO) channels with correlated paths and transmit antennas are considered. In such systems, optimal precoding with only covariance feedback is derived using the minimum Pair-wise Error Probability (PEP) criterion; linear and non-linear precoders are designed. The proposed precoding only needs the statistical knowledge of the channel at the transmitter, which significantly reduces the feedback requirements. Both linear and non-linear precoders substantially improve the system Bit Error Rate (BER) for OSTBC OFDM in transmit-antenna and path-correlated channels.