Multi-element fiber for space-division multiplexing

Abstract

Abstract.A novel approach of using multi-element fiber (MEF) technology in space-division multiplexing (SDM) systems is presented. This paper reviews the progress in fabrication and characterization of MEF based both ultralow crosstalk transmission and amplifier fibers. Passive 3-element MEFs have been successfully demonstrated for application in telecommunications. An active 5-element MEF amplifier has also been demonstrated in a novel multiport cladding-pumped configuration, in which a central un-doped multi-mode pump fiber-element is surrounded by four Er/Yb-doped active fiber-elements. MEF is compatible with current WDM systems, and there is no need to develop specialized multiplexing/demultiplexing components. Moreover, it offers a smooth upgrade to SDM systems.

Multi-Element Fiber Technology for High-Capacity Optical Communication Systems

“…The attenuation and dispersion characteristics of MEF have been observed to be similar to those of SSMF drawn from the same starting preform [8], showing no additional penalty with respect to SSMF, although this remains to be proven at the 0.2 dB/km level. MEFs fabricated so far exhibit crosstalk levels below 100 dB between the various fiber-elements [7]. An important feature of the MEF is that it lends itself directly to the implementation of SDM amplifiers.…”

“…If the fiberelements are made to optically contact one another, a cladding-pumped multi-element erbium doped fiber amplifier (ME-EDFA) can be manufactured [8]. By making the central fiber-element a pump delivery fiber of pure silica with no core, pump light can be coupled into the ME-EDFA erbium-doped fiber-elements [7]. Since a single multimode pump diode is shared among all the fiber-elements this approach offers a cost effective SDM amplifier solution.…”

“…Multi-element Fibers (MEF) have been proposed as an alternative to these existing approaches [6][7][8]. This fiber geometry exhibits very low levels of crosstalk, avoiding the requirement for MIMO processing, is fully compatible with standard single mode fiber (SSMF) systems and offers several potential benefits from a device integration perspective, making it a suitable candidate for an effective implementation of SDM in commercial optical networks.…”

Space Division Multiplexing Using Multi-Element Fibers

“…Moreover, since MIMO requires access to all the spatial channels to successfully decouple the information channels, it constrains the flexibility of the network by restricting switching in the spatial dimensions [6]. Multi-element Fibers (MEFs) have been proposed as an alternative to these existing approaches [7][8][9]. This fiber geometry exhibits very low levels of crosstalk and is fully compatible with SSMF systems, making it a suitable candidate for an effective implementation of SDM in commercial optical networks.…”