Simulation of Birefringence and Polarization Mode Dispersion Characteristics in Various Commercial Single Mode Fibers

Single mode optical fiber operation for long haul distance communication media has rapidly developed. Several efforts are implemented to reduce and control the attenuation and absorption of signal propagation. However, fiber parameters still experienced interference with internal and external factors that result birefringence and polarization mode dispersion such as bending power losses, signal widening and increasing wavelengths. In order to reduce and optimize the interference which is experimentally difficult to demonstrate because of the very long fibers hence a numerical simulation is set with perspective of twisted fiber disorder as a function of wavelengths and fiber geometry. The simulation evaluates the various refractive indices, radius of fibers and wavelength sources. The quality of optical fiber interference can be identified from the twisted power losses values with different variations of twisted radius. This model obtained indicates the greatest power losses occurring as a function of radius, refractive indices and wavelength. The results show that normalized frequency value has important role in determining the effectiveness the optical fiber performance and stability of power deliver. The addition of wavelength can affect the fibers experiencing birefringence and polarization mode dispersion occurring at wavelength of telecommunication regimes.

Technical specifications and spectral performance characteristics of dispersion flattened fiber (DFF) in optical fiber systems

This work has clarified the technical specifications and spectral performance characteristics of dispersion flattened fiber (DFF) in optical fiber systems. Effective nonlinear refractive index and first, second order polarization mode dispersion against spectral wavelength with fiber length of 1000 m and coupling length of 20 m are simulated and demonstrated. Total DFF fiber losses/dispersion performance parameters are investigated and simulated by using OptiFiber simulation. Zero DFF fiber dispersion and its dispersion slope are demonstrated clearly in details. The dominant modes and the cutoff data theoretical values based these modes for the proposed DFF fiber is determined and simulated in a clear manner.

Fixed scattering section length with variable scattering section dispersion based optical fibers for polarization mode dispersion penalties

This study has clarified the fixed scattering section length with variable scattering section dispersion based optical fibers for polarization mode dispersion penalties at high data rates. The max. signal power/min. noise power is simulated against time after fiber length of 500 km with various scattering section dispersion. The overall total light power is simulated after fiber length of 500 km with various scattering section dispersion. In addition to the overall total electrical power is clarified through APD receiver at fiber length of 500 km with various scattering section dispersion. Eye diagram analyzer for signal quality is also simulated through APD receiver at fiber length of 500 km with various scattering section dispersion. The max. Q Factor, electrical signal power after APD receiver variations against scattering section dispersion variations for various data rates.

Palliation of Four-Wave Mixing in Optical Fibers Using Improved DSP Receiver

A long haul optical communication system (LHOCS) is one of the key resources to fulfill the higher capacity requirements in future communication networks. To launch LHOCS, the system mainly faces high order nonlinear effects. The four-wave mixing (FWM) is one of the major nonlinear effects, which limits the transmission distance. Therefore, in this paper, an advanced duo-binary (DB) modulation scheme-based system is evaluated by employing an improved digital signal processing (IDSP) approach at the receiver side to suppress the FWM effect. In addition, an analytical analysis is also performed for the proposed system. To observe the difference between the IDSP and conventional digital signal processing (DSP), the various performance metrics such as bit error rate (BER), Q-factor, and optical signal-to-noise ratio (OSNR) parameters are evaluated. Variable channel spacing along with polarization mode dispersion (PMD) are analyzed at several ranges of input powers and fiber lengths. The analytical and simulation-based calculations exhibit the effectiveness of the proposed model and hence, FWM effect are compensated to achieve 500 km optical fiber propagation range with a BER below 10−6.

Impact of Wind Gust on High-Speed Characteristics of Polarization Mode Dispersion in Optical Power Ground Wire Cables

Polarization mode dispersion is recognized as a key factor limiting optical transmission systems, particularly those fiber links that run at bit rates beyond 10 Gbps. In-line test and characterization of polarization mode dispersion are thus of critical importance to evaluate the quality of installed optical fibers that are in use for high-speed signal traffics. However, polarization-based effects in optical fibers are stochastic and quite sensitive to a range of environmental changes, including optical cable movements. This, in turn, gives rise to undesired variations in light polarization that adversely impair the quality of the signal transmission in the link. In this work, we elaborate on experimental testing and theoretical analysis to asses changes of polarization mode dispersion in optical fibers that are caused by environmental variations, here wind gusts in particular. The study was performed on commercially harnessed optical fibers installed within optical power ground wire cables, taking into account different weather conditions. More specifically, we showed that changes caused by wind gusts significantly influence the differential group delay and the principal state of polarization in those optical fibers. For this, we experimentally measured a number of parameters to characterize light polarization properties. Measurements were carried out on C-band operated fiber-optic link formed by 111-km-long power ground wire cables and 88 spectral channels, with a test time step of 1 min during 12 consecutive days. Variations in differential group delay allowed for sensitive testing of environmental changes with measured maxims up to 10 ps under the worst wind conditions. Moreover, measured parameters were used in a numerical model to assess the quality of transmitted high-bit-rate optical signals as a function of wind conditions. The analysis revealed a negligible impact of wind on a 10 Gbps transmission, while substantial influence was noticed for higher bit rates up to 100 Gbps. These results show promises for efficient sensing of environmental changes and subsequent monitoring of the quality of recently used fiber-optic link infrastructures.