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Updated: Jul 3, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Simultaneous chromatic dispersion and PMD compensation by using coded-OFDM and girth-10 LDPC codes.
Ivan B Djordjevic1, Lei Xu, Ting Wang
1University of Arizona, Department of Electrical and Computer Engineering, Tucson, AZ 85721, USA. ivan@ece.arizona.edu
Optics Express
|July 9, 2008
Summary
Low-density parity-check (LDPC) coded orthogonal frequency division multiplexing (OFDM) effectively compensates for chromatic dispersion and polarization mode dispersion (PMD). This method achieves 10 Gb/s over 6500 km SMF with minimal signal penalty.
Area of Science:
- Optical communication systems
- Digital signal processing
Background:
- Chromatic dispersion (CD) and polarization mode dispersion (PMD) degrade optical signal quality over long-haul fiber transmission.
- Orthogonal frequency division multiplexing (OFDM) offers robustness against chromatic dispersion.
- Low-density parity-check (LDPC) codes provide powerful error correction capabilities.
Purpose of the Study:
- To investigate the efficacy of LDPC-coded OFDM for simultaneous compensation of CD and PMD.
- To evaluate the performance of this scheme at a 10 Gb/s aggregate data rate over extended fiber lengths.
Main Methods:
- Employing LDPC codes with a girth of 10 and a coding rate of 0.8.
- Utilizing training sequence-based channel estimation for adaptive compensation.
- Simulating transmission over 6500 km of standard single-mode fiber (SMF) with 100 ps differential group delay (DGD).
Main Results:
- Simultaneous compensation of significant accumulated dispersion (6500 km SMF) and DGD (100 ps) was achieved.
- The system penalty was maintained within 1.5 dB compared to a back-to-back configuration.
- The proposed scheme demonstrates high performance for robust optical data transmission.
Conclusions:
- LDPC-coded OFDM is a viable and efficient solution for mitigating both CD and PMD in high-speed optical networks.
- The combination of advanced coding and modulation techniques enables reliable long-haul data transmission.
- This approach offers a promising path towards future high-capacity optical communication systems.
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