Timing synchronization performance of N-continuous symbol padding OFDM

Both N-continuous OFDM and N-continuous symbol padding OFDM (NCSP-OFDM) are modulation techniques that achieve a low sidelobe transmission signal. This study compares the timing synchronization performance of these modulation techniques by using a simple non-data-aided algorithm. The experimental results indicate that the timing metric curve of N-continuous OFDM becomes flat near the ideal timing to detect an OFDM symbol. On the other hand, the curve of NCSP-OFDM exhibits a sharp peak, although its time has the gap against the ideal timing. We propose a gap-corrected ML estimation of time offset. From the results of numerical experiment, we find that the proposed estimation improves the timing synchronization performance of NCSP-OFDM as compared with that of N-continuous OFDM.