Proposal of OFDM channel estimation method using discrete cosine tramsform

The Orthogonal Frequency Division Multiplexing (OFDM) system with a frequency domain equalization method has a potential capability to provide the high speed data with keeping high signal quality even under severe multi-path fading environments. To realize the potential performances of OFDM technique, it is essential to realize the higher accurate channel estimator. This paper first presents the problems of conventional channel estimator based on Discrete Fourier Transform (DFT) method and then proposes a novel channel estimator on the basis of Discrete Cosine Transform (DCT) method to overcome the problems of DFT method. The frequency interpolation method based on the DCT method is also proposed to provide the accurate and efficient channel estimator, which can be used in the OFDMA and MIMO systems of using the scattered pilot symbols. This paper presents the theoretical and computer simulation results to demonstrate the effectiveness of proposed DCT method as comparing with those for the conventional DFT method.