Theoretical CSPR Analysis and Performance Comparison for Four Single-Sideband Modulation Schemes With Kramers-Kronig Receiver

Abstract

Recently, high-speed optical transmission using single-side-band (SSB) modulation with Kramers-Kronig (KK) scheme has gained great attention due to its high spectral efficiency (SE) and capability of electronic chromatic dispersion compensation (CDC), which can be widely employed in optical metro networks as a promising transmission scheme. To our knowledge, the carrier-signal power ratio (CSPR) is the key parameter to SSB-based systems and the optimum CSPRs can vary distinctly in different SSB modulation schemes. In this paper, the SSB-based KK systems with four kinds of SSB signal generation schemes are investigated, i.e. optical carrier-assisted SSB (OCA-SSB), virtual carrierassisted SSB (VCA-SSB), SSB subcarrier modulation (SSB SCM) with IQ modulator (IQM) and with dual-drive Mach-Zehnder modulator (DDMZM) respectively. Here, the detailed theoretical derivations of these modulation processing are given and the theoretical relationship between device parameters and the CSPR has been further studied for the different SSB schemes. In order to verify those theoretical analyses, a 224-Gb/s direct detection (DD) transmission with SSB 16-ary quadrature amplitude modulation (16-QAM) signal has been demonstrated based on four SSB generation methods. The results show that theoretical derivations are closely consist with numerical analysis, such as V bias in the scheme of SSB SCM with IQM and optical modulation index (OMI) in SSB SCM with DDMZM. Therefore, our research can provide a theoretical guidance of appropriate device parameter configuration so as to achieve the optimum performance for SSB systems.

A Review of Self-Coherent Optical Transceivers: Fundamental Issues, Recent Advances, and Research Directions

“…In addition, different carrier and optical single-sideband (SSB) signal generation have been presented [12,[53][54][55][56]. For instance, the optical SSB signal generation regarding the offset SSB and virtual SSB (VSSB) has been presented [12].…”

“…Apart from the bias-induced generation being considered, digital virtual and optical generation schemes have been discussed [54]. Moreover, detailed theoretical derivations of the SSB-based modulation, as well as the relationship between the device parameters and the CSPR have been presented [55,56].…”

“…Apart from the fact that the presented work in [14] was brief, some salient concepts of the simplified transceivers such as carrier/SSB signal generation, SSBN mitigation, spectral broadening, CSPR optimization, and field and polarization recoveries were not discussed. Moreover, the great majority of the contributions focused on one-or two-optical-SSB-signal generation [12,[53][54][55][56], while most also presented one or two SSBN mitigation/digital linearization schemes [12,21,22,29,30,46,54,[57][58][59]. Furthermore, in [55,56], the SSB signal generation was well presented, while little or no consideration was given to the SSBN mitigation/digital linearization schemes.…”

“…Moreover, the great majority of the contributions focused on one-or two-optical-SSB-signal generation [12,[53][54][55][56], while most also presented one or two SSBN mitigation/digital linearization schemes [12,21,22,29,30,46,54,[57][58][59]. Furthermore, in [55,56], the SSB signal generation was well presented, while little or no consideration was given to the SSBN mitigation/digital linearization schemes.…”

“…For instance, the SSB-DMT, SSB-PAM4, and SSB-CAP schemes have been gaining significant attention [53,[82][83][84][85]. This is mainly due to the notable offered advantages such as the improved SE and significant resistance to chromatic dispersion because of the EDC capability [55,56]. Comprehensive information on the SSB signal generation and associated concepts is given in Section 4.…”