National Institute of Information and Communications Technology (NICT) 4-2-1, Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan.
Opt Lett. 2010 Jan 1;35(1):13-5. doi: 10.1364/OL.35.000013.
We experimentally demonstrate linewidth-tolerant real-time 40-Gbit/s(10-Gsymbol/s) 16-quadrature amplitude modulation. We achieved bit-error rates of <10(-9) using an external-cavity laser diode with a linewidth of 200 kHz and <10(-7) using a distributed-feedback laser diode with a linewidth of 30 MHz, thanks to the phase-noise canceling capability provided by self-homodyne detection using a pilot carrier. Pre-equalization based on digital signal processing was employed to suppress intersymbol interference caused by the limited-frequency bandwidth of electrical components.
我们通过实验演示了线宽容忍的实时 40-Gbit/s（10-Gsymbol/s）16 正交幅度调制。我们使用线宽为 200 kHz 的外腔激光二极管实现了<10(-9)的误码率，使用线宽为 30 MHz 的分布式反馈激光二极管实现了<10(-7)的误码率，这要归功于自外差检测提供的相位噪声消除能力使用导频载波。基于数字信号处理的预均衡用于抑制电组件有限频率带宽引起的码间干扰。
