Measuring the longitudinal distribution of four-wave mixing efficiency in dispersion-shifted fibers

Fiber-based optical parametric amplifiers and their applications

“…However, as the impact of the nonlinear phase mismatch increases, can be advantageously utilized to increase and flatten the operational bandwidth by optimizing [7], [42]. A second factor to take into account for the OPA gain bandwidth is the fact that in a real fiber is slightly distributed along the fiber length [9], [43], [44]. This will broaden the resulting gain bandwidth compared to a fixed wavelength but will decrease the peak gain.…”

Pulse broadening induced by dispersion fluctuations in optical fibers

“…The answer depends on the time-scale at which fluctuations occur. Temperature-induced dispersion fluctuations are likely to vary slowly and it may be possible to compensate for them by using an adaptive dynamic compensation technique [12][13][14][15]. In contrast, any mechanism that leads to rapid dispersion fluctuations may be difficult to eliminate fully.…”

“…If the core radius of the fiber or the distribution of dopants inside the fiber varies along the fiber length in a random fashion, b varies with z because of the waveguide contribution to the effective mode index of the fiber [1]. If the environmental variables such as temperature fluctuate at different locations of fiber, bðzÞ fluctuates with time as well, because the material dispersion of fiber depends on temperature [11][12][13][14]. Our objective is to find pulse broadening induced by such fluctuations in addition to that resulting from the average value of b.…”

“…Such variations are static, i.e., they do not change with time. Second, environmental changes such as temperature fluctuations can introduce time-dependent changes in the fiber dispersion [11][12][13][14]. Such changes are relatively small but can add to considerable fluctuations for long-haul fiber links, especially at high bit rates, for which the requirements on accumulative dispersion become quite stringent.…”

Fiber Measurement Technique Based on OTDR

“…However, conventional measurement techniques [5,6] can only determine the average chromatic dispersion of either a short or a long fiber. Recently, there have been some reports on measurement techniques for estimating chromatic dispersion distribution along a fiber [7][8][9]. As these measurement techniques are based on optical nonlinear effects, the measurement distance is limited.…”