Abstract

A precoding technology with a digital signal processor and high-speed DACs is a promising key enabler for realizing next-generation higher-order modulation systems. Achievement of a DAC operating speed of 40 GS/s or beyond is a prerequisite for high-speed precoded transmission. In this paper, the application of and the trends in optical precoding technology are reviewed. A high-speed DAC for optical communications at 40 Gb/s and beyond is introduced. To achieve a DAC suitable for digital signal processor based high order modulation, an interleaved DAC and a high-speed multiplexer are key technologies.

© 2011 Optical Society of America