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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
40-Gbaud 16-QAM transmitter using tandem IQ modulators with binary driving electronic signals
Guo-Wei Lu1, Mats Sköld, Pontus Johannisson
1Photonics Laboratory, Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology, SE- 412 96 Göteborg, Sweden. guowei@chalmers.se
Abstract:
We propose a novel 16-quadrature amplitude modulation (QAM) transmitter based on two cascaded IQ modulators driven by four separate binary electrical signals. The proposed 16-QAM transmitter features scalable configuration and stable performance with simple bias-control. Generation of 16-QAM signals at 40 Gbaud is experimentally demonstrated for the first time and visualized with a high speed constellation analyzer. The proposed modulator is also compared to two other schemes. We investigate the modulator bandwidth requirements and tolerance to accumulated chromatic dispersion through numerical simulations, and the minimum theoretical insertion attenuation is calculated analytically.
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