학술논문

Demonstration of Tunable Optical Aggregation of QPSK to 16-QAM Over Optically Generated Nyquist Pulse Trains Using Nonlinear Wave Mixing and a Kerr Frequency Comb
Document Type
Periodical
Source
Journal of Lightwave Technology J. Lightwave Technol. Lightwave Technology, Journal of. 38(2):359-365 Jan, 2020
Subject
Communication, Networking and Broadcast Technologies
Photonics and Electrooptics
Optical mixing
Optical modulation
Optical pulses
Phase shift keying
Optical pumping
Kerr frequency comb
nonlinear wave mixing
optical aggregation
optical Nyquist pulses
Language
ISSN
0733-8724
1558-2213
Abstract
A tunable and reconfigurable optical aggregation system is experimentally demonstrated. Optical Nyquist pulses are generated on multiple channels using a microresonator-based Kerr optical frequency comb and insertion of uniform lines by an intensity modulator. Data are modulated on optically generated Nyquist pulses and aggregated through nonlinear wave mixing in a periodically poled lithium niobate (PPLN) waveguide. Two quadrature-phase-shift-keying (QPSK) channels are aggregated to a single 16-quadrature amplitude modulation (16-QAM) channel of Nyquist pulses. To demonstrate the system tunability, we perform aggregation over different baud rates and different modulation formats. The reconfigurability of the system is demonstrated by aggregating two binary-phase-shift-keying (BPSK) channels into a QPSK or a 2-level amplitude-shift keying and a 2-level phase-shift keying (2-ASK/2-PSK) channel by tuning the relative phase and amplitude of the inputs. Furthermore, three BPSK channels are aggregated into one 4-ASK/2-PSK channel. The quality of the aggregated channel is investigated using two different approaches for wave mixing in the PPLN waveguide.