• Journal of the Optical Society of Korea
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• v.16 no.2
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• pp.95-100
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• 2012

We show that the minimum EOP (eye-opening penalty) obtained by tunable dispersion compensation is a function of a figure of merit for a nonlinear process, $I_0L_{eff}$, where $I_0$ is the optical intensity and $L_{eff}$ is the effective length of the interaction region. Using this rule, we do not need to conduct nonlinear simulations in all the cases of signal power and transmission length to obtain the signal distortion in dispersion-managed optical transmission. Instead, we need to conduct a simulation in only one case of a signal power and find the functional relation, and then we can obtain the values of the signal distortion in other cases using the discovered functional relation. This technique can reduce the number of nonlinear simulations to less than 10%.

• Journal of Advanced Navigation Technology
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• v.19 no.6
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• pp.595-600
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• 2015

The implementation possibility of the flexible optical network configuration using the non-midway optical phase conjugator (OPC) in the dispersion-managed (DM) optical link for wavelength division multiplexed (WDM) transmission is demonstrated in this paper. It is confirmed that the implementation possibility of flexible link configuration is more increased, as number of fiber spans is more bigger and the residual dispersion per span (RDPS) is more large. It is also confirmed that the non-midway OPC link, in which RDPS of the latter half transmission section (after OPC) is decided by the averaged RDPS of the former half transmission section (before OPC), has more advantage for the flexible network configuration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.351-353
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• 2018

The compensation characteristics are investigated as a function of the averaged residual dispersion per span (RDPS), which is different in each half transmission section, in dispersion-managed optical transmission links with a randomly distributed single mode fiber lengths and RDPS.

• Journal of information and communication convergence engineering
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• v.15 no.4
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• pp.205-211
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• 2017

Combining dispersion-managed optical links with midway optical phase conjugation (OPC) is a possible method of compensating for optical signal distortion due to group velocity dispersion and nonlinear Kerr effects. Although an improvement in the performance of these optical links has been reported, the fixed residual dispersion per span (RDPS) that is typically used restricts the flexibility of link configurations. Thus, in this paper, a flexible dispersion-managed link configuration, comprising artificial distributions of linearly/nonlinearly incremented RDPS, is proposed. Simulations show that a descending distribution of RDPS before the midway OPC, and an ascending distribution of RDPS after the midway OPC, gives the best artificial distribution pattern as the number of fiber spans is increased, regardless of the RDPS incrementation method.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.8
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• pp.1235-1240
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• 2013

We investigate an approximate analytic expression of signal distortion caused by the interaction between self-phase modulation (SPM) and dispersion in the dispersion-managed optical transmission where the dispersion is optimally compensated. From the analytic study, we obtain the analytic expression of the signal distortion in dispersion-managed optical transmission system. To confirm the validity of the analytic expression, we show that the eye-opening penalties calculated by the analytic expression correspond with the simulation results. Using the analytic result, we can easily estimate the signal distortion without complex nonlinear simulations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.964-966
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• 2015

The effect of the deviations of single mode fiber lengths and residual dispersion per span (RDPS) on the compensation for the distorted WDM signals in the dispersion-managed optical links with the specially artificial distributions of the lengths of SMFs and RDPSs. The considered artificial distribution is following; the lengths of SMF and RDPSs between the adjacent fiber span are more descended in the half transmission section from transmitter to optical phase conjugator (OPC), and those are more ascended in the rest half transmission section from OPC to the receiver, as number of fiber spans are more increased.

• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.408-414
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• 2020

The method of overcoming the limitation of optical phase conjugator applied into optical long-haul link for transmitting high capacity wavelength division multiplexed (WDM) channels was investigated. The configuration of optical link was based on dispersion-managed link, in which dispersion compensating fiber inserted into each fiber span with single mode fiber, and optical phase conjugator was added into suitable location of link. The maximum number of fiber spans as a function of the launch power of WDM channels in optical link with optical phase conjugator placed at the proposed location was induced and compared for analyzing the compensation performance of the distorted WDM channels. It was confirmed that the more optical phase conjugator depart from the midway of total transmission length, the less the distorted WDM channels was compensated, however, it was also confirmed that the degradation of compensation can be overcome by the suitable value of residual dispersion per span and by the reasonable choice of fiber span controlling total dispersion accumulated in overall transmission link.

• Journal of Advanced Navigation Technology
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• v.23 no.6
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• pp.570-576
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• 2019

The configuration of dispersion-managed optical link with optical phase conjugator, which is placed at the non-midway of total transmission length, is proposed for implementing of the flexible optical network. The optical phase conjugator is located between the former half transmission section and the latter half transmission section, which are consisted of 6 fiber spans and 14 fiber spans respectively, and the averaged RDPS of each half transmission section are inconsistence. And, the artificial distribution of each fiber span's RDPS, which are gradually increased/decreased as the span numbers are increased, is adopted to compensate for the distorted wavelength division multiplexed channels. From the simulation results, it is confirmed that the compensation in dispersion-managed link configured by a special distribution pattern among 16 proposed patterns, in which the RDPS of each fiber spans are gradually decreased/increased in the former/latter half section with the small deviation, is suitable to compensate for the distorted wavelength division multiplexed channels.

• Journal of information and communication convergence engineering
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• v.7 no.3
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• pp.372-376
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• 2009

In this paper, new and simple optical transmission link with fixed dispersion management (DM) scheme, i.e., pre(post) compensation and residual dispersion per span (RDPS) are fixed to net residual dispersion (NRD) = 0 ps/nm, and optical phase conjugator (OPC) having optimal position depending on launch power in WDM transmission system is proposed. Also, effective launch power range of WDM channels resulting 1 dB eye opening penalty (EOP) is induced as a function of OPC position. First, it is confirmed that, for applying DM into WDM transmission link fixed pre(post)compensation and RDPS, which are independence on exact system parameters except launch power, sufficiently are used in WDM links, but OPC with optimal position is needed for effective compensating impairments of WDM channels. And, it is confirmed that effective launch power is broader in case of RDPS = 100 ps/nm than in RDPS = 50 ps/nm. But, it is shown that the best OPC position offset is -0.6 km from a point of view of power window, which is defined as difference between maximum and minimum effective launch power.

• Journal of information and communication convergence engineering
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• v.13 no.4
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• pp.228-234
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• 2015

The system performance improvement in dispersion managed (DM) links combined with optical phase conjugator (OPC) for compensating for optical signal distortion due to group velocity dispersion and nonlinear fiber effects has been reported. However, in DM link combined OPC, the equalities of the lengths of single-mode fibers (SMFs), the length of dispersion compensating fibers (DCFs), the dispersion coefficient of DCF, and the residual dispersion per span (RDPS) with respect to an OPC restrict a flexible link configuration. Thus, in this paper, we propose a flexible optical link configuration with inequalities of link parameters, the so-called "pseudo-symmetric configuration." Simulation results show that, in the restricted RDPS range of 450 ps/nm to 800 ps/nm, the improvement in the system performance of the proposed pseudo-symmetrically configured optical links is better than that of the asymmetrically configured optical links. Consequently, we confirmed that the proposed pseudo-symmetric configuration is effective and useful for implementing a reconfigurable long-haul wavelength-division multiplexing (WDM) network.