Semiblind Channel and Carrier Frequency-Offset Estimation for Orthogonally Space-Time Block Coded MIMO Systems

The problem of joint channel and carrier frequency offset (CFO) estimation is addressed in the context of multiple-input multiple-output (MIMO) communications using orthogonal space-time-block codes (OSTBCs). A new semiblind method is proposed to jointly estimate the channel matrix and the CFO parameter. Our method blindly estimates the CFO parameter along with a low-dimensional subspace where the channel is located, and then uses a few training blocks to extract the channel parameters from this subspace.