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09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
None pilot-tones and training sequence assisted OFDM technology based on multiple-differential amplitude phase shift
Bo Liu1, Lijia Zhang, Xiangjun Xin
1State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Optics Express
|October 6, 2012
Summary
This study introduces a new pilot-free optical orthogonal frequency division multiplexing (OFDM) system using multi-differential amplitude phase shift keying (mDAPSK). This technology enables efficient channel estimation and successful 41.31 Gb/s data transmission over 160-km SMF.
Area of Science:
- Optical Communications
- Signal Processing
- Digital Modulation
Background:
- Orthogonal frequency division multiplexing (OFDM) is a key technology in optical systems.
- Pilot-assisted channel estimation in optical OFDM consumes significant bandwidth.
- Differential detection offers an alternative for robust demodulation.
Purpose of the Study:
- To propose and experimentally validate a novel pilot-assisted orthogonal frequency division multiplexing (OFDM) technology for optical systems.
- To eliminate the need for bandwidth-intensive pilot tones or training sequences for channel estimation.
- To evaluate the performance of multi-differential amplitude phase shift keying (mDAPSK) in optical OFDM.
Main Methods:
- Implementation of a non-pilot-assisted OFDM system utilizing multi-differential amplitude phase shift keying (mDAPSK).
- Differential detection employed during demodulation for inherent channel estimation.
- Experimental transmission of a 41.31 Gb/s 64DAPSK-OFDM signal over 160-km single mode fiber (SMF).
Main Results:
- Successful transmission of a 41.31 Gb/s optical OFDM signal without pilot tones.
- Demonstration of effective channel estimation through differential detection.
- Comparative performance analysis between mDAPSK and multi-quadrature amplitude modulation (mQAM).
Conclusions:
- The proposed mDAPSK-OFDM technology offers a promising, pilot-free solution for optical communication systems.
- Differential detection effectively replaces traditional pilot-assisted channel estimation methods.
- mDAPSK-OFDM exhibits significant potential for future high-speed optical transmission systems.
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