Beyond 240 Gb/s per Wavelength Optical Transmission Using Coded Hybrid Subcarrier/Amplitude/Phase/Polarization Modulation

Abstract

Abstract-In this letter, we propose a low-density parity-check coded hybrid subcarrier/amplitude/phase/polarization (H-SAPP) modulation scheme suitable to achieve a 240-Gb/s single-channel transmission rate over optical channels. The proposed scheme doubles the aggregate transmission rate achievable by eight-quadrature amplitude modulation while providing 2-dB optical signal-tonoise ratio performance improvement at a bit-error-ratio (BER) of 10 6 . Moreover, H-SAPP can increase the aggregate rate of the hybrid amplitude/phase/polarization scheme while maintaining the BER performance intact.Index Terms-Coherent detection, high-speed optical transmission, hybrid subcarrier/amplitude/phase/polarization (H-SAPP) coded modulation, low-density parity-check (LDPC) codes, optical communications.

Robust Multidimensional Optical Modulation Based on Hybrid Subcarrier/Amplitude/Phase/Dual Polarization for Wavelength-Division Multiplexing Systems

“…The use of polarization-mode dispersion can improve the coding gain due to the error floor and the iterative exchange of extrinsic soft-bit reliabilities between posterior probabilities. Hussam developed a way to implement such a modulation with different sub-carriers in a 3D space using coded hybrid sub-carrier/amplitude/phase/polarization (H-SAPP) [14]. Using Stokes parameters, H-SAPP allows 20 points to be incorporated into a 3D constellation mapping in the form of a dodecahedron inscribed in a Poincaré sphere based on regular polyhedrons [15].…”

Waveform design for higher-level 3D constellation mappings and its construction based on regular tetrahedron cells

“…However, the conventional 3D lattice constellation mapping based on hexahedron, as one of the five polyhedrons, does not provide optimum mapping since only 2 dimensions, rather than 3, are used sufficiently in the 3D space. And then, different combinations of regular polyhedrons based on the dual characteristics were utilized to form a higher-level constellation with multiple amplitude levels [14,15]. The regular icosahedra and dodecahedrons were combined to generate a 32-ary and higher-level 3D constellation, while a honeycomb of tetrahedrons and octahedrons was used to tessellate the 3D space in another structure [14].…”

“…The regular icosahedra and dodecahedrons were combined to generate a 32-ary and higher-level 3D constellation, while a honeycomb of tetrahedrons and octahedrons was used to tessellate the 3D space in another structure [14]. In [15], the regular dodecahedron were employed to realize a two-subcarrier hybrid polarization modulation in optical communication. However, there is a limit to the number of combinations of regular polyhedrons, leading to limitations in producing accessible structures of higherlevel 3D constellation.…”

Orbital angular momentum (OAM) based LDPC-coded free-space optical communication

“…In order to satisfy high-bandwidth demands of future optical networks while keeping the system cost and power consumption reasonably low, we proposed the use of multidimensional coded modulation schemes in a series of articles [1], [2]. The key idea behind this proposal was to exploit various degrees of freedom already available for the conveyance of information on a photon such as frequency, time, phase, amplitude and polarization to improve the photon efficiency, while keeping the system cost reasonable low.…”

“…Because OAM eigenstates are orthogonal, in principle, arbitrary number of bits per single photon can be transmitted. Since our application of multiple photon degrees of freedom has mostly been related to the fiber-optics communication so far [1], [2], the OAM as a degree of freedom has not been studied. The ability to generate/analyze states with different OAMs, by using interferometric or holographic methods [3], [4], allows the realization of FSO communication systems with ultra-high photon efficiencies expressed in terms of number of bits per photon.…”