Frequency Offset and Timing Synchronization for OFDM Utilizing PN Sequence

In orthogonal frequency division multiplexing (OFDM) systems, time offset and frequency affects its performance. A novel carrier frequency offset and timing offset detection scheme is proposed based on PN sequence, two same PN sequence pilot are inserted in Time-domain of OFDM symbols, when they are correlated with receiver PN sequence, frame synchronization can be obtained, then symbol synchronization is got basing slide windowed technique and minimum mean square error method. Depending on the two correlated peaks of PN sequences, coarse frequency offset is estimated. Basing cyclic prefix(CP) , an accumulated scheme is proposed to estimate the exactitude frequency offset. Excellent synchronization performance can be implemented in timevary mulitpaths, and these schemes are proven by simulations.