Open Access
Spectrum-efficient hybrid PAM-DMT for intensity-modulated optical wireless communication
Author(s) -
Baolong Li,
Simeng Feng,
Wei Xu
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.392127
Subject(s) - orthogonal frequency division multiplexing , transmitter , spectral efficiency , bit error rate , transmission (telecommunications) , electronic engineering , computer science , wireless , optical wireless , modulation (music) , latency (audio) , intensity modulation , channel (broadcasting) , optics , telecommunications , physics , engineering , phase modulation , phase noise , acoustics
In optical wireless communication (OWC), the superimposed optical orthogonal frequency division multiplexing (O-OFDM), such as layered asymmetrically clipped O-OFDM (LACO-OFDM), can improve spectrum efficiency by appropriately combining multiple O-OFDM signals for simultaneous transmission. However, it suffers from increased receiver complexity and latency. Therefore, a novel architecture of hybrid pulse-amplitude-modulated discrete multitone modulation (HPAM-DMT) is proposed in this paper to support a spectrum-efficiency OWC link. In HPAM-DMT, a PAM-DMT signal is carefully designed by using the real parts of subcarriers and is then superimposed on the classic PAM-DMT signal for simultaneous transmission, which fully exploits the spectrum in terms of subcarriers. Moreover, thanks to the well-designed aritecture of the two superimposed PAM-DMT signals, the proposed HPAM-DMT achieves the same spectrum efficiency as the LACO-OFDM, with much lower complexity and latency. Notable improvement of the bit-error rate (BER) performance is observed for the proposed HPAM-DMT compared to LACO-OFDM under the corruption of the transmitter nonlinearity. Moreover, HPAM-DMT achieves a relatively higher power efficiency than conventional O-OFDM schemes, which makes it a competitive O-OFDM scheme for IM/DD-based OWC.