Blind Carrier Frequency Offset Estimation for MIMO-OFDM with Constant Modulus Constellations via Rank Reduction Criterion

In this paper, we propose a new blind carrier frequency offset (CFO) estimator for multiple-input-multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems with constant modulus constellation. The proposed estimator exploits a rank reduction criterion and works in the general MIMO scenarios where no space-time block coding is assumed. As compared with several existing competitors, the proposed estimator does not suffer from performance error floor as SNR increases; thus, it can behave better under the moderate- and high-SNR regions. The Cramer-Rao bound of CFO estimation for MIMO-OFDM with constant modulus constellation is derived, and the numeral results are provided to corroborate the proposed studies.