Multi-Band OFDM Transmission at 100 Gbps With Sub-Band Optical Switching

Abstract

In this paper, we present an original work on subwavelength optical switching performed over a coherent multiband orthogonal frequency-division multiplexing (MB-OFDM) super-channel operating at 100 Gbps. After having demonstrated that dual-polarization MB-OFDM (DP-MB-OFDM) is as efficient as single-carrier dual-polarization quaternary phase shift keying (DP-QPSK) technology to transport 100 Gbps data-rate over a 10 × 100-km G.652 fiber-based transmission line, we show that optical add-drop of OFDM sub-bands as narrow as 8 GHz inside a 100 Gbps DP-MB-OFDM signal constituted of four sub-bands is feasible in the middle of this 1000-km transmission line. The flexible optical add-drop multiplexer (FOADM) implemented here is constituted by the association of an ultra-narrow pass-band and stopband optical filter. The design and realization of such ultra-selective optical filters is presented, while the impact of their physical features over the quality of transmission is discussed. To prove that several add-drop multiplexers can be cascaded, our FOADM is introduced into a G.652 fiber-based recirculating loop and the impact of the cumulated filtering transfer function as well as the crosstalk inside the OADM are investigated. A typical use case for the introduction of such FOADM into long-haul transport networks is given, and the capital expenditure (CAPEX) cost advantage for the multi-layer transport networks is highlighted. By the proof of concept delivered here, combination of super-channel and subwavelength optical switching pushes network flexibility far away of what is today proposed by system vendors, opening new horizons for an optimized use of multi-layer transport networks.

QPSK 3R regenerator using a phase sensitive amplifier

“…1(a). The propagating signals suffer distortions introduced not only by the nonlinear transmission fibre and the inline amplifiers, but also, by the multiplexers/demultiplexers that select and recombine the signals at the regeneration and switching nodes, which is particularly troublesome in optical super channel networks [16,17]. At the regeneration nodes the degraded signals are demultiplexed and launched to the PSA elements of the 3R subsystems, see Fig.…”

112-Gbit/s Passive Optical Pod Interconnect for small data centers using Pulse Amplitude Modulation

“…(b) shows the optical spectrum of the 8-PAM signal overlapped with the BPF model for a 75-GHz grid. Based on available technology [17], we limit BPF slope to less than 800 dB/nm. Slope values for each possible case are presented on TABLE IV.…”

Design and performance evaluation of narrowband rectangular optical filter based on stimulated Brillouin scattering in fiber

“…QPSK and 16-QAM constellations are then obtained by off-line processing. A more precise description of OFDM signal generation and detection is in [14,15]. The validity of the SBS amplification with different gains for OFDM signal has been assessed.…”