Frequency domain joint channel and phase noise estimation in OFDM WLAN systems

A frequency domain channel estimator for OFDM is derived in the presence of phase noise. In an OFDM frame transmission (e.g., WLAN), channel estimation is performed based on the full-block pilot symbol at the preamble. The estimate is then used to decode subsequent OFDM data symbols in the same frame. Channel estimation, however, can be severely degraded in the presence of phase noise. The proposed approach removes the effect of phase noise when estimating the channel response. When this improved channel estimate is used to detect OFDM data symbols, large improvement in bit error rate is observed.