Extension of N-Continuous OFDM Precoder Matrix for Improving Error Rate

The modulation technique of N -continuous orthogonal frequency division multiplexing (OFDM) has lower sidelobes than those of the original OFDM as a result of the continuous connection with higher-order derivatives between the OFDM symbols. Compared with the other sidelobe suppression schemes, for example, cancellation carrier insertion, and windowing, N continuous OFDM does not require an extended guard interval nor the insertion of a wide guard band or cancellation carriers. However, N -continuous OFDM requires an iterative algorithm to remove the correction symbols from received symbols at the receiver and the large power of the correction symbols in the high-frequency area results in unavailable bandwidth. Here, we propose an extension of the N -continuous OFDM precoder matrix that flattens the bias power caused by the correction symbols in all frequency areas. Numerical experiments show that the proposed method improves the error rate performance without degrading the sidelobe suppression performance. The proposed method can also reduce the unavailable bandwidth.