Time-Frequency Channel Equalization for OFDM Communication Systems

In this paper, we present a computationally efficient, time-frequency (TF) based channel estimation method for OFDM channels whose frequency response may be changing over a single transmit symbol. The discrete evolutionary transform is used to obtain a complete model of a multi-path, fading and frequency selective channel. A TF receiver is designed to detect the sent data by using estimated channel parameters. Performance of the proposed method is tested on different levels of channel noise, and Doppler frequency shifts.

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