A method and apparatus on coherent demodulation of OFDM signal for radio LAN systems

摘要

PURPOSE: A coherent demodulation of OFDM for wireless LAN system and apparatus of the same are provided to demodulate correctly data symbols by selecting and upgrading channel estimation values, periodically. CONSTITUTION: A coherent demodulation of OFDM for wireless LAN system and apparatus of the same includes a data symbol extraction process, a channel estimation process, a data channel estimation value selection process, and a channel equalization process. The data symbol extraction process is to remove a subcarrier from a received sample sequence and extracts a data symbol therefrom. The channel estimation process is to estimate a channel state of a preamble part from a training symbol of a long period, the channel states of each pilot symbol by using a reference data symbol, and the channel states of each data symbol. The data channel estimation value selection process is to select the estimated value of the data channel by using the estimated value of the training channel and the estimated value of the pilot channel. The channel equalization process is to perform a channel equalization process.