Comparison of FTN and Nyquist Signaling in Conditions of Equal Spectral Efficiency

Abstract

Root raised cosine (RRC) pulses can provide occupied frequency bandwidth reduction and intersymbol interference (ISI) elimination at receiver. The drawback of RRC pulses is high peak-to-average power ratio (PAPR). One of the ways to reduce the PAPR is to apply Faster-than-Nyquist (FTN) signaling. In this paper we compare PAPR and energy efficiency of FTN and Nyquist signals under conditions of the same spectral efficiency. With the help of simulation modeling it is shown that for certain values of roll-off factor FTN signals based on RRC pulses can provide about 1 dB gain in PAPR. It is also possible to achieve the gain in bit error rate (BER) for the case of FTN with QAM-16 compared to Nyquist signals with QAM-32 when decision feedback algorithm is used.