Title :
Directly PAM-4 Modulated 1530-nm VCSEL Enabling 56 Gb/s/
Data-Center Interconnects
Author :
Karinou, F. ; Prodaniuc, C. ; Stojanovic, N. ; Ortsiefer, M. ; Daly, A. ; Hohenleitner, R. ; Kogel, B. ; Neumeyr, C.
Author_Institution :
Eur. Res. Center, Huawei Technol. Dusseldorf GmbH, Munich, Germany
Abstract :
We demonstrate a 56 Gb/s four-level pulse-amplitude modulation (PAM-4) transmission using direct detection and a long-wavelength 18-GHz bandwidth vertical-cavity surface-emitting laser as directly modulated light source for short-reach inter- and intra-connects in datacenters and short-reach networks. Error-free transmission over 2 km at 7% hard-decision forward-error correction threshold is achieved by applying powerful equalization schemes at the receiver side. Three equalization schemes, i.e., a maximum likelihood estimation (MLSE), a feed-forward equalizer (FFE), and a combination of the FFE and the MLSE are thoroughly investigated, and the performance comparison between them is carried out.
Keywords :
computer centres; feedforward; forward error correction; laser cavity resonators; maximum likelihood estimation; optical interconnections; pulse amplitude modulation; surface emitting lasers; PAM-4 modulated VCSEL; bandwidth 18 GHz; bit rate 56 Gbit/s; data-center interconnects; direct detection; directly modulated light source; distance 2 km; equalization schemes; error-free transmission; feed-forward equalizer; four-level pulse-amplitude modulation transmission; hard-decision forward-error correction threshold; long-wavelength bandwidth vertical-cavity surface-emitting laser; maximum likelihood estimation; receiver side; short-reach inter-connects; short-reach intra-connects; short-reach networks; wavelength 1530 nm; Adaptive optics; Bit error rate; Complexity theory; Maximum likelihood estimation; Modulation; Receivers; Vertical cavity surface emitting lasers; Pulse amplitude modulation; equalizers; maximum likelihood estimation; optical interconnects; vertical cavity surface emitting lasers;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2015.2444096