Title :
Few-Mode Fibers Supporting More Than Two LP Modes For Mode-Division-Multiplexed Transmission With MIMO DSP
Author :
Mori, Takayoshi ; Sakamoto, Takanori ; Wada, Masaki ; Yamamoto, Takayuki ; Yamamoto, Fumihiko
Author_Institution :
Access Network Service Syst. Labs., NTT Corp., Tsukuba, Japan
Abstract :
We propose a transmission fiber for mode-division-multiplexed transmission with multiple-input multiple-output (MIMO) digital signal processing supporting four and six linearly polarized (LP) modes over the C + L band. We show numerically that a graded-index core can flexibly tune the differential mode group delay (DMD) and a cladding trench can flexibly control the guiding mode number. We optimized the spacing of the core and trench. Accordingly, we can achieve a few-mode operation of more than two LP modes and low DMD while preventing the high-refractive index difference that leads to manufacturing difficulties and any loss increase. Finally, we successfully fabricated fibers for use in a C + L band WDM-MDM transmission with MIMO DSP, and realized a transmission fiber with a total absolute DMD of less than 40 ps/km for four-LP mode operation and of less than 70 ps/km for six-LP mode operation over the entire C + L band.
Keywords :
MIMO communication; digital signal processing chips; refractive index; wavelength division multiplexing; MIMO DSP; WDM MDM transmission; cladding trench; differential mode group delay; digital signal processing; few mode fibers; graded index core; high refractive index difference; mode division multiplexed transmission; transmission fiber; Indexes; MIMO; Optical fiber couplers; Optical fiber networks; Optical fiber polarization; Propagation constant; Refractive index; Differential mode delay; few-mode fibers; multiple-input multiple-output;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2014.2327619
