  Discrete Cosine Transform (DCT) can be used instead of conventional Discrete
Fourier Transform (DFT) for the Orthogonal Frequency Division Multiplexing
(OFDM) construction, which offers many advantages. In this paper, the
Multiple-Input-Multiple-Output (MIMO) DCT-OFDM is enhanced using a proposed
Cosine Domain Equalizer (CDE) instead of a Frequency Domain Equalizer (FDE).
The results are evaluated through the Rayleigh fading channel with Co-Carrier
Frequency Offset (Co-CFO) of different MIMO configurations. The average bit
error probability and the simulated time of the proposed scheme and the
conventional one is compared, which indicates the importance of the proposed
scheme. Also, a closed formula for the number of arithmetic operations of the
proposed equalizer is developed. The proposed equalizer gives a simulation time
reduction of about 81.21%, 83.74% compared to that of the conventional LZF-FDE,
and LMMSE-FDE, respectively for the case of 4x4 configuration.
