The adaptive algorithm of symbol timing and carrier phase estimation in OFDM systems

An adaptive algorithm of symbol timing and carrier phase synchronization in OFDM system is proposed, based on pilot symbols. The algorithm exploits the properties of DFT, that is, the offset in time (frequency) domain corresponds to the rotation of phase in frequency (time) domain. The synchronization can be divided into two steps. Firstly, The coarse timing and fine carrier phase can be adaptively estimated simultaneously using our algorithm. Secondly, the above symbol synchronization algorithm acquire synchronization alignment to within several samples, this residual offset will result in the rotation of every sample of the OFDM symbol, the estimation and correction of this residual timing offset are included in our algorithm. Simulations show the coarse timing synchronization can be used in an acquisition mode, the estimation and correction of residual timing error can overcome the effect completely. The carrier phase estimator shows a good performance that suffice for OFDM systems. The advantage of this algorithm is simple computation and little resource loss due to pilot symbols