[Show abstract][Hide abstract] ABSTRACT: We summarize the latest advances in space-division multiplexing (SDM) for increasing the capacity per fiber strand. We discuss SDM fibers, recent SDM transmission experiments, subsystems suitable for SDM systems, as well as integrated components able to manipulate multiple spatial modes within a single optical device.
[Show abstract][Hide abstract] ABSTRACT: We experimentally demonstrate broadband four-wave mixing (FWM) between two spatial modes of a 5-km-long few-mode fiber. We show that, in contrast to FWM in single-mode fibers, inter-modal FWM (IM-FWM) can be better phase matched for waves well separated in frequency (a few THz) than when they are closely spaced (tens of GHz).
Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), 2013; 01/2013
[Show abstract][Hide abstract] ABSTRACT: We transmitted five wavelength channels and six spatial and polarization modes over a 209-km-long hybrid few-mode fiber span. The fiber supports six spatial and polarization modes, and consists of a first section of large effective area depressed-cladding few-mode fiber followed by a graded-index few-mode fiber. The differential group delay is compensated by using fiber spools with differential group delay of opposite sign. Low-loss three-spot mode couplers are used to couple to the few-mode fiber, and backward pumped-distributed Raman amplification is used to overcome the fiber loss. The 40-Gb/s QPSK signals with an aggregate capacity of 1.2 Tb/s are recovered by coherent multiple-input-multiple-output off-line digital signal processing. The impulse response at various span lengths is compared and analyzed in detail.
[Show abstract][Hide abstract] ABSTRACT: Since the first deployments of fiber-optic communication systems three decades ago, the capacity carried by a single-mode optical fiber has increased by a staggering 10 000 times. Most of the growth occurred in the first two decades with growth slowing to ten times in the last decade. Over the same three decades, network traffic has increased by a much smaller factor of 100, but with most of the growth occurring in the last few years, when data started dominating network traffic. At the current growth rate, the next factor of 100 in network traffic growth will occur within a decade. The large difference in growth rates between the delivered fiber capacity and the traffic demand is expected to create a capacity shortage within a decade. The first part of the paper recounts the history of traffic and capacity growth and extrapolations for the future. The second part looks into the technological challenges of growing the capacity of single-mode fibers by presenting a capacity limit estimate of standard and advanced single-mode optical fibers. The third part presents elementary capacity considerations for transmission over multiple transmission modes and how it compares to a single-mode transmission. Finally, the last part of the paper discusses fibers supporting multiple spatial modes, including multimode and multicore fibers, and the role of digital processing techniques. Spatial multiplexing in fibers is expected to enable system capacity growth to match traffic growth in the next decades.
Proceedings of the IEEE 01/2012; 100(5):1035-1055. · 6.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We present designs for a low-loss mode coupler based on multiple Gaussian spots that can selectively address spatial and polarization modes of a few-mode fiber. In particular we show a design optimized for a few-mode fiber with 12 spatial and polarization modes (LP01, the twofold degenerate LP11 and LP21, and LP02), with a mode dependent loss
Photonics Society Summer Topical Meeting Series, 2012 IEEE; 01/2012
[Show abstract][Hide abstract] ABSTRACT: We experimentally demonstrate transmission of 6 mode-multiplexed 20-Gbd-QPSK signals over 1200 km of three-core microstructured fiber (3C-MSF). An aggregate single-wavelength capacity of 240 Gbit/s is recovered by off-line 6×6 coherent multiple-input multiple-output (MIMO) digital signal processing.
European Conference on Optical Communication (ECOC); 09/2011
[Show abstract][Hide abstract] ABSTRACT: We show that implementing pre- and post-dispersion compensation in electronic nonlinearity compensation can significantly improve the performance of 112-Gb/s PDM-QPSK coherent systems. More electronic compensation stages are required for a system without optical dispersion compensators (ODCs) than that with ODCs.
Optical Communication (ECOC), 2010 36th European Conference and Exhibition on; 10/2010
[Show abstract][Hide abstract] ABSTRACT: We discuss criteria to select advanced optical modulation formats in order to mitigate impairments specific to various classes of fiber-optic communication systems.
Optical Amplifiers and Their Applications; 06/2004