QRD-Based Precoded MIMO-OFDM Systems With Reduced Feedback
QR Decomposition (QRD)-based precoded MIMO-OFDM systems with reduced feedback are proposed to convert the MIMO-OFDM channel into layered subchannels. QRD-M is further combined with either Singular Value Decomposition (SVD) or Geometric Mean Decomposition (GMD) of the time-domain channel impulse response matrix. As a result, the receiver in the proposed systems only needs to feed back information describing one precoding matrix for all carriers. Simulation results confirm the Bit-Error-Rate (BER) and throughput performance superiority of the proposed systems compared to conventional SVD per-carrier precoding schemes.