A Novel Algebraic Carrier Frequency Offset Estimator for ASTC-MIMO-OFDM Systems Over a Correlated Frequency-Selective Channel

This paper presents a new algebraic carrier frequency offset (CFO) estimation technique for multiple-input-multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) system, to overcome the sensitivity of algebraic space-time codes (ASTCs) to frequency synchronization in quasi-static correlated Rayleigh frequency-selective fading channels. The technique uses a preamble and is thus particularly suitable for burst-mode communications. The preamble consists of orthogonal training sequences that are simultaneously transmitted from the various transmit antennas. The proposed system exploits all subcarriers in the frequency domain, which provides a remarkable performance improvement, and reaches the Cramer-Rao lower bound (CRLB) at a high signal-to-noise ratio. The proposed method is compared with three known CFO estimators in the literature: Cyclic-Prefix-based (CP), Moose, and Classen techniques that show clear advantages.