Demonstration of automatic dispersion equalization in 40 Gbit/s OTDM transmission

Experimental Demonstration and Analytic Derivation of Chromatic Dispersion Monitoring Technique Based on Clock-frequency Component

“…In conclusion, the analytic expressions of the pure CFC, the half CFC, and the CFC after a reverse diode function are derived in Eq. (6), (7), and (13), respectively. The analytic results are shown as a dotted line in Fig.…”

“…Until now, there have been substantial efforts to develop the chromatic dispersion monitoring techniques, which include the techniques based on clock-frequency component (CFC), subcarrier tone, and phase-modulation to amplitudemodulation conversion [2][3][4][5][6][7][8][9][10][11]. Among the techniques, the technique using the power change of the CFC in the received signal seems to be the simplest because it does not need to add any extra modulation to the data signal [7][8][9][10][11].…”

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.…”