A 56 Gb/s PAM4 VCSEL-Based LiFi Transmission With Two-Stage Injection-Locked Technique

A 56 Gb/s four-level pulse amplitude modulation (PAM4) light-based WiFi (LiFi) transmission based on a 680-nm/5.4-GHz vertical-cavity surface-emitting laser (VCSEL) with a two-stage injection-locked technique is proposed and demonstrated. Experimentally results show that a 5.4-GHz VCSEL with a two-stage injection-locked technique is effective for 56 Gb/s PAM4 LiFi transmissions. To the authors' knowledge, it is the first one to adopt a 680-nm VCSEL transmitter with two-stage injection-locked technique in a 56 Gb/s PAM4 LiFi transmission. A pair of doublet lenses is employed in the proposed PAM4 VCSEL-based LiFi transmissions to enhance the free-space link. The link performances of the proposed PAM4 LiFi transmissions have been analyzed in real time. Good bit error rate performance and three independent clear eye diagrams are obtained over a 20-m free-space link. Such a proposed 56 Gb/s PAM4 VCSEL-based LiFi transmission with two-stage injection-locked technique has the potential to play a significant role in future wireless infrastructure for providing high transmission rate and long free-space transmission distance effectively.

[1]  S. Mohrdiek,et al.  Chirp reduction of directly modulated semiconductor lasers at 10 Gb/s by strong CW light injection , 1994 .

[2]  Ming C. Wu,et al.  Novel cascaded injection-locked 1.55-mum VCSELs with 66 GHz modulation bandwidth. , 2007, Optics express.

[3]  Martin Schell,et al.  Low Switching Voltage Mach–Zehnder Modulator Monolithically Integrated With DFB Laser for Data Transmission up to 107.4 Gb/s , 2016, Journal of Lightwave Technology.

[4]  Hai-Han Lu,et al.  45  Gb/s PAM4 transmission based on VCSEL with light injection and optoelectronic feedback techniques. , 2016, Optics letters.

[5]  Chao Yang,et al.  IM/DD-Based 112-Gb/s/lambda PAM-4 Transmission Using 18-Gbps DML , 2016, IEEE Photonics Journal.

[6]  Ilya Lyubomirsky,et al.  Four 45 Gbps PAM4 VCSEL based transmission through 300 m wideband OM4 fiber over SWDM4 wavelength grid. , 2016, Optics express.

[7]  Dan Sadot,et al.  Single channel 112Gbit/sec PAM4 at 56Gbaud with digital signal processing for data centers applications , 2015, 2015 Optical Fiber Communications Conference and Exhibition (OFC).

[8]  Hai-Han Lu,et al.  Bidirectional fiber-wireless and fiber-VLLC transmission system based on an OEO-based BLS and a RSOA. , 2016, Optics letters.

[9]  P. Andrekson,et al.  4-PAM for high-speed short-range optical communications , 2012, IEEE/OSA Journal of Optical Communications and Networking.

[10]  Erik G. Ström,et al.  On the optimality of the binary reflected Gray code , 2004, IEEE Transactions on Information Theory.

[11]  A. Chen,et al.  Single chip 52 Gb/s PAM4 transmission through −58 and +10 ps/nm chromatic dispersion using directly modulated laser , 2016, 2016 Optical Fiber Communications Conference and Exhibition (OFC).

[12]  Peng-Chun Peng,et al.  20-Gbps optical LiFi transport system. , 2015, Optics letters.

[13]  Hai-Han Lu,et al.  10 m/25 Gbps LiFi transmission system based on a two-stage injection-locked 680 nm VCSEL transmitter. , 2015, Optics letters.

[14]  S. Fu,et al.  Transmission of 2 × 56 Gb/s PAM-4 signal over 100 km SSMF using 18 GHz DMLs. , 2016, Optics letters.

[15]  Chris Kocot,et al.  52 Gbps PAM4 receiver sensitivity study for 400GBase-LR8 system using directly modulated laser. , 2016, Optics express.