DCT-Based Channel Estimation Method for MIMO-OFDM Systems

This paper presents two discrete cosine transform (DCT)-based pilot-symbol-aided channel estimation methods using different pilot arrangement schemes. By exploiting the properties of DCT, both proposed methods mitigate the aliasing effect introduced in discrete Fourier transform (DFT)-based channel estimation method when the multi-path fading channels have non-sample-spaced path delays. Of these two DCT-based channel estimation methods, one reduces the additive white Gaussian noise (AWGN) and inter-carrier interference (ICI) significantly by iteration, while with reasonable constraint and phase shifted pilot sequences for each transmitter antenna, the other one can achieve highly efficient and accurate estimation without sacrificing much system overhead. The computer simulation results demonstrate effectiveness of the proposed DCT-based channel estimation methods.