Channel Estimation Algorithm Using an Improved DFT for MIMO-OFDM Systems
The Improved DFT-based Channel Estimation Algorithm for MIMO-OFDM System uses the symmetric property to extend the LS estimate in frequency domain, and calculates the changing rate of the leakage energy, and selects useful paths by the changing rate. The conversion from a very long (or infinite) sequence to a manageable size entails a type of distortion called leakage, which is manifested as a loss of detail in the DTFT. Choice of an appropriate sub-sequence length is the primary key to minimizing that effect. When the available data (and time to process it) is more than the amount needed to attain the desired frequency resolution, a standard technique is to perform multiple DFTs.