5 × 5  Gbps DWDM optical system with DCF and cascaded repeaters techniques.

Area of Science:

• Optical Communications
• Telecommunications Engineering
• Signal Processing

Background:

• Dense wavelength division multiplexing (DWDM) systems face performance limitations due to signal dispersion and attenuation.
• Dispersion leads to optical pulse broadening, while attenuation degrades signal quality, impacting system capacity and reach.

Purpose of the Study:

• To investigate and compare the effectiveness of dispersion compensation fiber (DCF) and cascaded repeaters in mitigating linear and nonlinear impairments in DWDM systems.
• To evaluate the performance of these techniques using two modulation formats: carrier-suppressed return zero (CSRZ) and optical modulators.
• To analyze the impact of different channel spacings (100 GHz and 50 GHz) on system performance.

Main Methods:

• Simulated DWDM system performance using dispersion compensation fiber (DCF) and cascaded repeaters.
• Employed carrier-suppressed return zero (CSRZ) and optical modulator formats.
• Tested system behavior at channel spacings of 100 GHz and 50 GHz.
• Assessed performance based on quality factors.

Main Results:

• At 100 GHz channel spacing, cascaded repeaters achieved a quality factor of 37 for both CSRZ and optical modulation, outperforming DCF (27 for CSRZ).
• At 50 GHz channel spacing, cascaded repeaters yielded a quality factor of 31 (CSRZ and optical modulation), with DCF achieving 27 (CSRZ) and 19 (optical modulator).
• DCF showed better compatibility with the CSRZ modulation format.

Conclusions:

• Cascaded repeaters offer superior performance in mitigating dispersion and attenuation issues in DWDM systems compared to DCF, particularly at narrower channel spacings.
• The choice between DCF and cascaded repeaters depends on the specific modulation format and channel spacing requirements.
• Optimizing repeater placement and modulation schemes is crucial for enhancing DWDM system efficiency.