Optics-simplified DSP for 50 Gb/s PON downstream transmission using 10 Gb/s optical devices
Journal article, 2020

Directly-modulated laser (DML) is widely employed in intensity modulation and direct detection (IMDD) system due to its low cost and high output power. However, the corresponding frequency chirp is regarded as one of the main disadvantages for its application in passive optical networks (PONs). In this paper, we theoretically analyze the frequency response evolution of DML based system under different chirp and dispersion conditions, proving that the system bandwidth can be improved by interactions between negative dispersion and DML chirp. Based on this concept, we experimentally demonstrated downstream 50 Gb/s PAM4 signal transmission over 20 km single-mode fiber (SMF) access based on the 10 Gb/s DML operating at 1310 nm and avalanche photodiode (APD). A dispersion-shifted fiber (DSF) providing -150 ps/nm dispersion at 1310 nm in the optical line terminal (OLT) is used to pre-equalize the frequency response of bandwidth-limited directly modulated signals in the optical domain. Thanks to our proposed dispersion-supported equalization (DSE) technique, the system bandwidth can be improved by 5 GHz. Feed-forward equalization (FFE), decision feedback equalization (DFE) and Volterra filter are employed to evaluate the signal performance improvement, respectively. By evaluating the receiver sensitivity, the DSE combined with FFE scheme shows 2 dB improvement than the complex Volterra algorithm, indicating its potential to reduce the complexity of digital signal processing (DSP) and therefore a lower cost and power consumption in PON.

Directly modulated laser (DML)

Digital signal processing(DSP)

Dispersion-supported equalization (DSE)

Direct detection

Passive optical network (PON).

Author

Lei Xue

Chalmers, Electrical Engineering, Communication and Antenna Systems, Optical Networks

Shanghai Jiao Tong University

Lilin Yi

Shanghai Jiao Tong University

Weisheng Hu

Shanghai Jiao Tong University

Rui Lin

Chalmers, Electrical Engineering, Communication and Antenna Systems, Optical Networks

Jiajia Chen

Chalmers, Electrical Engineering, Communication and Antenna Systems, Optical Networks

Journal of Lightwave Technology

0733-8724 (ISSN)

Vol. 38 3 583-589 8844825

5G System Technological Enhancements Provided by Fiber Wireless Deployments

European Commission (EC), 2017-06-01 -- 2020-05-31.

Areas of Advance

Information and Communication Technology

Subject Categories

Telecommunications

Atom and Molecular Physics and Optics

Condensed Matter Physics

DOI

10.1109/JLT.2019.2942438

More information

Latest update

12/17/2020