International Journal of Innovations in Engineering and Technology (IJIET)
In this paper, the authors study the joint estimation of In-phase and Quadrature-phase (I/Q) imbalance, Carrier Frequency Offset (CFO), and channel response for Multiple-Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems using training sequences. A new concept called Channel Residual Energy (CRE) is introduced. They show that by minimizing the CRE, they can jointly estimate the I/Q imbalance and CFO without knowing the channel response. The proposed method needs only one OFDM block for training and the training symbols can be arbitrary.