Synchronization Sequence Generated by Modified Park Algorithm for NC-OFDM Transmission

The traditional schemes for the synchronization in the OFDM transmission, such as the Schmidl&Cox, Minn and Park algorithms, utilize the only every second or fourth subcarriers of the preamble symbol. This regular subcarrier occupation pattern does not meet the requirement of Non-Continuous OFDM (NC-OFDM) with the arbitrary spectrum holes free from the interference with the primary users. In this letter, a special synchronization sequence with non-continuous spectrum is constructed and can be evaluated at the receiver with a modified version of the Park algorithm. Our new synchronization concept not only complies with the traditional Park algorithm, but also has the considerable smaller sidelobes in the correlation function evaluated for the time synchronization, so that a higher synchronization detection probability is obtained.