Abstract
We report for the first time on the limitations in the operational power range of few-mode fiber based transmission systems, employing 28 Gbaud quadrature phase shift keying transponders, over 1,600 km. It is demonstrated that if an additional mode is used on a preexisting few-mode transmission link, and allowed to optimize its performance, it will have a significant impact on the pre-existing mode. In particular, we show that for low mode coupling strengths (weak coupling regime), the newly added variable power mode does not considerably impact the fixed power existing mode, with performance penalties less than 2dB (in Q-factor). On the other hand, as mode coupling strength is increased (strong coupling regime), the individual launch power optimization significantly degrades the system performance, with penalties up to ~6 dB. Our results further suggest that mutual power optimization, of both fixed power and variable power modes, reduces power allocation related penalties to less than 3 dB, for any given coupling strength, for both high and low differential mode delays.
Highlights
IntroductionWith the ever increasing demand for high information rates and current advances in bandwidth intense user-end applications (online gaming, ubiquitous video, etc.), the available transmission capacity for single mode optical fiber is exhausting at a very fast rate, and radical solutions are sought in order to be able to keep up with rapidly growing traffic demand
With the ever increasing demand for high information rates and current advances in bandwidth intense user-end applications, the available transmission capacity for single mode optical fiber is exhausting at a very fast rate, and radical solutions are sought in order to be able to keep up with rapidly growing traffic demand
It can be seen that as the launch power of the second mode is varied, the transmission performance is initially limited by optical signal-to-noise ratio (OSNR), and reaches an optimum power, beyond which performance is degraded due to nonlinear fiber impairments
Summary
With the ever increasing demand for high information rates and current advances in bandwidth intense user-end applications (online gaming, ubiquitous video, etc.), the available transmission capacity for single mode optical fiber is exhausting at a very fast rate, and radical solutions are sought in order to be able to keep up with rapidly growing traffic demand. While MDM solutions enable high capacity growth, these systems present complex tradeoffs to system designers. One such challenge is associated with linear and nonlinear mode coupling effects, which strongly connect the achieved capacity to the achievable transmission distance [6,7,8]. Are considered an essential part of a mode division multiplexed system, leading to modal crosstalk, it is critical to analyze the impact of individual optimal mode launch powers, since various modes have different propagation characteristics. We observe that in the absence of linear mode coupling the relative powers in the two modes has negligible impact on transmission performance in both cases, due to insignificant inter modal crosstalk –dependent on the fiber type. We further show that in this case such penalties may be minimized by an appropriate balance of launch powers, and identify the relative impact of linear and nonlinear mode coupling on the optimum power levels
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
