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Published on: June 8, 2018
High spectral efficiency modulation scheme based on joint interaction of orthogonal compressed chirp division
This study introduces a novel high spectral efficiency (SE) modulation scheme combining orthogonal compressed chirp division multiplexing (OCCDM) and power superimposed code (PSC) for IM/DD systems. The technique experimentally achieved over double the baseline SE, showing potential for next-generation PON development.
Area of Science:
- Optical communications
- Signal processing
- Fiber optics
Background:
- Intensity modulation and direct detection (IM/DD) systems face limitations in spectral efficiency (SE).
- Orthogonal chirp division multiplexing (OCDM) offers spectral compression but requires further enhancement for SE.
- Power superimposed code (PSC) can increase data rates but needs integration with advanced multiplexing techniques.
Purpose of the Study:
- To propose and experimentally validate a novel high spectral efficiency (SE) modulation scheme.
- To investigate the joint interaction of orthogonal compressed chirp division multiplexing (OCCDM) and power superimposed code (PSC) in IM/DD systems.
- To assess the impact of these technologies on bit error rate (BER) and SE.
Main Methods:
- Implementation of orthogonal compressed chirp division multiplexing (OCCDM) with spectral compression.
- Integration of power superimposed code (PSC) for multi-user transmission on the same chirp.
- Experimental transmission over a 2 km, 7-core fiber span.
- Assessment of BER performance in power, frequency, and joint domains.
Main Results:
- The combined OCCDM and PSC scheme significantly enhances spectral efficiency (SE).
- A spectral bandwidth compression factor (α) of 0.9 and a power distribution ratio of 4 balanced BER and SE.
- Achieved an SE increase of 2.22 times the baseline value.
- Demonstrated successful transmission over a multi-core fiber link.
Conclusions:
- The proposed modulation scheme offers a substantial increase in SE for IM/DD systems.
- This technology shows promise for future development of passive optical networks (PON).
- The joint interaction of OCCDM and PSC provides a viable path towards higher capacity optical communication systems.
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