Abstract:Further investigation is given to a kind of carrier frequency offset (CFO) blind estimation algorithm based on time domain received signal reconstruction in OFDM systems, and the four aspects that affect the estimation accuracy are analyzed. For minimizing the residual carrier frequency offset, a kind of decision-directed carrier frequency synchronization loop is given by introducing a feedback factor into the frequency compensation. Better carrier frequency tracking performance can be gotten by adjusting the loop gain. The residual frequency offset can be restricted within 1% of the carrier spacing even if lager frequency drift exists, if bit SNR reaches 9dB.