Performance of Iterated EKF Technique to Estimate Time Varying Channel Using Pilot Assisted Method in MIMO-OFDM System

In this paper Iterative Extended Kalman Filter (IEKF) technique has been proposed to estimate the time varying channel for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing systems (OFDM). Channel state information (CSI) plays major role to improve the performance of any wireless communication system for different fading channels to detect the data. Kalman Filter (KF) is most powerful technique for linear processing and it is more suitable to estimate additive white gaussian noise (AWGN) channels. But it is not fit for non-linear problems since wireless channels have some nonlinear characteristics. In this paper, IEKF technique has been proposed to estimate time varying channel, and comparative analysis has been done with the techniques which are proposed based on LS, MMSE and EKF. Simulations also demonstrated that, channel estimation based on IEKF having significant improvement in aspect of bit error rate (BER) and mean square error (MSE) with modest computational complexity.

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