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Updated: May 12, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Random coupling between groups of degenerate fiber modes in mode multiplexed transmission
Cristian Antonelli1, Antonio Mecozzi, Mark Shtaif
1Dept. of Physical and Chemical Sciences, University of L’Aquila, 67100 L’Aquila, Italy. cristian.antonelli@univaq.it
Optics Express
|April 24, 2013
Summary
Crosstalk in spatially multiplexed optical transmission is mainly caused by wavenumber mismatch and mode coherence, not group velocity differences. Crosstalk measurements are inherently noisy due to a standard deviation comparable to the average value.
Area of Science:
- Optical Communications
- Photonics
- Signal Processing
Background:
- Spatially multiplexed optical transmission enables higher data rates by using multiple optical modes.
- Degenerate modes in optical fibers can lead to crosstalk, degrading signal quality.
- Understanding crosstalk mechanisms is crucial for designing robust optical communication systems.
Purpose of the Study:
- To analyze the impact of random coupling on crosstalk between degenerate modes in spatial multiplexing.
- To identify the primary factors determining average crosstalk levels.
- To investigate the variability and noise characteristics of crosstalk measurements.
Main Methods:
- Theoretical analysis of random coupling effects in optical waveguides.
- Modeling of crosstalk based on wavenumber mismatch, perturbation correlation length, and mode coherence length.
- Statistical analysis of crosstalk standard deviation in relation to its average value.
Main Results:
- Average crosstalk is predominantly influenced by wavenumber mismatch, random perturbation correlation length, and degenerate mode coherence length.
- Deterministic group velocity differences have a negligible effect on average crosstalk.
- The standard deviation of crosstalk is comparable to its average value, indicating inherent noise in measurements.
Conclusions:
- Random coupling is a key driver of crosstalk in spatially multiplexed systems.
- Wavenumber mismatch and mode coherence are critical parameters for managing crosstalk.
- The inherent noisiness of crosstalk measurements necessitates careful interpretation and advanced signal processing techniques.
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