Performance Analysis of a Low-Interference N-Continuous OFDM Scheme

This paper investigates two issues of power spectrum density (PSD) and bit error rate (BER) of an N-continuous orthogonal frequency division multiplexing (NC-OFDM) aided low-interference time-domain scheme, when the smooth signal is designed by the linear combination of basis signals truncated by a window. Based on the relationship between the continuity and sidelobe decaying, the PSD performance is first analyzed and compared, in terms of the highest derivative order (HDO) N and the length of the smooth signal L. Since the high-order derivative of the truncation window has the finite continuity, the N-continuous signal has two finite continuities, which may have different continuous derivative orders. In this case, we develop a close PSD expression by introducing another smooth signal, which is also linearly combined by other basis signals, to explain the sidelobe decaying related to N and L. Then, in the context of BER, considering the multipath Rayleigh fading channel, based on the effect of the delayed tail of the smooth signal to the received signal, we provide a procedure for calculating the BER expressed in the form of an asymptotic summation.Comment: 7 pages, 6 figure

Time-Domain N-continuous GFDM

Generalized frequency division multiplexing (GFDM) has been a candidate multicarrier scheme in the 5th generation cellular networks for its flexibility of transmitter filter in time and frequency. However, for the circularly shaped transmitter filter, GFDM provides limited performance gain of sidelobe suppression. In this paper, we propose a scheme, called time-domain N-continuous GFDM (TD-NC-GFDM), to reduce the discontinuities caused by the GFDM transmitter filter and achieve promising sidelobe suppression gain. Based on time-domain N-continuous orthogonal frequency devision multiplexing (TD-NC-OFDM), TD-NC-GFDM signal can be obtained by superposing a smooth signal in the time domain. The smooth signal is linearly combined by basis signals in a new basis set related to GFDM transmitter waveform. To eliminate the interference caused by the smooth signal, two solutions are proposed. Firstly, a signal recovery algorithm for reception is adopted at the cost of high complexity. Thus, secondly, to simplify the TD-NC-GFDM receiver, a low-interference TD-NC-GFDM is proposed by redesigning the basis signals. A soft truncation of the basis signals in TD-NC-GFDM is given to design the basis signals in the low-interference TD-NC-GFDM. Then, the smooth signal is aligned with the beginning of the GFDM symbol and is added in the front part of the GFDM symbol. Moreover, for a big number of GFDM subsymbols, theoretical analysis proves that the signal-to-interference ratio (SIR) in TD-NC-GFDM is much higher than that in TD-NC-OFDM. Simulation results shows that TD-NC-GFDM can obtain significant sidelobe suppression performance as well as the low-interference TD-NC-GFDM, which can achieve the same BER performance as the original GFDM.Comment: single column, 19 pages, 10 figure

Weyl-Heisenberg Spaces for Robust Orthogonal Frequency Division Multiplexing

Design of Weyl-Heisenberg sets of waveforms for robust orthogonal frequency division multiplex- ing (OFDM) has been the subject of a considerable volume of work. In this paper, a complete parameterization of orthogonal Weyl-Heisenberg sets and their corresponding biorthogonal sets is given. Several examples of Weyl-Heisenberg sets designed using this parameterization are pre- sented, which in simulations show a high potential for enabling OFDM robust to frequency offset, timing mismatch, and narrow-band interference

125 Gbps Pre-Compensated Nonlinear Frequency-Division Multiplexed Transmission

Record-high data rate of 125 Gb/s and SE over 2 bits/s/Hz in burst-mode single-polarization NFDM transmissions were achieved over 976 km of SSMF with EDFA-only amplification by transmitting and processing 222 32 QAM-modulated nonlinear subcarriers simultaneouslyComment: This paper will be presented at ECOC 2017, Gothenburg, Swede