Abstract

In this article, we experimentally demonstrate dual O+C-band direct-detection wavelength division multiplexed (WDM) transmission over 50 km of standard single-mode fibre, wherein 4 × 40-Gb/s Nyquist on-off keying (OOK) modulation is used in the O-band whilst 4 × 40-Gb/s single-sideband (SSB) subcarrier modulation (SCM) with Kramers–Kronig (KK) detection is used in the C-band. A bismuth-doped fibre amplifier (BDFA) is used as the pre-amplifier in the O-band to extend the reach of the direct-detection system. It is demonstrated that the O-band exhibits superior receiver sensitivity relative to the C-band and its transmission performance is limited by the chromatic dispersion (CD), especially when longer reaches and wavelengths in the longer edge of the band are explored. In contrast, due to the adoption of the SSB format, the C-band shows enhanced tolerance to CD effects. In this case, some receiver sensitivity is sacrificed to accommodate the adoption of the KK detection which is used to eliminate the signal-to-signal beating interference of the SSB-SCM format. The inferior receiver sensitivity in the C-band is caused by (1) the higher CSPR requirement of the KK detection and (2) the restriction of small-signal modulation for the dual-drive Mach–Zehnder modulator to generate optical SSB signals. The results indicate the feasibility to further extend the reach of O-band transmission systems, which enables the possibility to realise dual O+C-band WDM transmission in intermediate- to long-haul optical networks.

Experimental demonstration of single-span 100-km O-band 4×50-Gb/s CWDM direct-detection transmission

Yang Hong, Natsupa Taengnoi, Kyle R. H. Bottrill, Naresh K. Thipparapu, Yu Wang, Jayanta K. Sahu, David J. Richardson, and Periklis Petropoulos
Opt. Express 30(18) 32189-32203 (2022)

Numerical and experimental study on the impact of chromatic dispersion on O-band direct-detection transmission

Yang Hong, Kyle R. H. Bottrill, Natsupa Taengnoi, Naresh K. Thipparapu, Yu Wang, Jayanta K. Sahu, David J. Richardson, and Periklis Petropoulos
Appl. Opt. 60(15) 4383-4390 (2021)

Experimental investigation of BDFA-based O-band direct-detection transmission using an optical recirculating loop

Yang Hong, Natsupa Taengnoi, Kyle R. H. Bottrill, Yu Wang, Jayanta K. Sahu, Periklis Petropoulos, and David J. Richardson
Opt. Express 31(7) 10978-10990 (2023)

C-band 120-Gb/s PAM-4 transmission over 50-km SSMF with improved weighted decision-feedback equalizer

Junwei Zhang, Xiong Wu, Lin Sun, Jie Liu, Alan Pak Tao Lau, Changjian Guo, Siyuan Yu, and Chao Lu
Opt. Express 29(25) 41622-41633 (2021)

Optical single side-band Nyquist PAM-4 transmission using dual-drive MZM modulation and direct detection

Mingyue Zhu, Jing Zhang, Xingwen Yi, Hao Ying, Xiang Li, Ming Luo, Yingxiong Song, Xiatao Huang, and Kun Qiu
Opt. Express 26(6) 6629-6638 (2018)