Improved frequency offset estimation technique in IEEE 802.11p environments

For inter-vehicle communications, the IEEE 802.11p standard has been employed in the U.S. and Europe. This configuration is an OFDM-based system, so it still has to cope with the issue of frequency synchronization. In this paper, a pilot-aided estimation technique is developed for the compensation of frequency offset in the IEEE 802.11p environments. The proposed synchronization algorithm utilizes the correlation between two identical halves of a training sequence after the appropriate usage of coarse compensation. As a result, the proposed estimation method indeed has the potentials to further enhance the mean square error (MSE) performance compared with the other conventional schemes. Some simulation results are given to illustrate the advantages of the proposed frequency offset estimation technique.

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