Abstract
Coherent detection and digital signal processing techniques have driven a remarkable development in optical transport technologies, enabling channels at 100 Gb/s to be transmitted over thousands of kilometers. Future optical communications systems will achieve even higher data rates (> 400Gb/s) through the deployment of superchannels, a designation for subcarrier multiplexing in the optical domain. In addition, a software-defined configuration of modulation format, transmission rate and coding scheme will enable advanced features such as automatic bandwidth provisioning and optimized spectrum allocation. However, compared with the wireless environment, optical systems are still very primitive in terms of intelligence, because their installation and operation require highly skilled manpower. The solution to this problem are adaptive optical transceivers, able to sense the channel conditions and to adapt their operation parameters to extend reach and reduce power consumption. In this paper we review a set of enabling concepts and algorithms of an adaptive optical transceiver, and discuss the challenges for its successful implementation.
Highlights
Optical communications systems are undergoing a major transmission capacity upgrade, achieving data rates beyond 100 Gb/s per wavelength with the combination of coherent detection, multilevel modulation formats and polarization multiplexing
At 400 Gb/s and 1 Tb/s, bandwidth limitations imposed by analog-to-digital converters (ADCs) require the use of sub-carrier multiplexing, which in optical communications has been called superchannel technology [1]
The optical network is being prepared for such upgrades with the deployment of a flexible grid, where the 50-GHz ITU-T grid is replaced by a fine-granularity channelization plan that allows to set up channels with different bandwidths [2]
Summary
Optical communications systems are undergoing a major transmission capacity upgrade, achieving data rates beyond 100 Gb/s per wavelength with the combination of coherent detection, multilevel modulation formats and polarization multiplexing. Performance requirements such as the net bit rate and required. We denote an operating point as being the set of parameters that define the transceiver performance, in particular, symbol rate, modulation format, chain of signal processing algorithms and coding scheme. In long-haul transmission, CD has a stable and long impulse response, in the order of the duration of hundreds of symbols It is compensated for by static digital filters whose coefficients need to be estimated by the receiver during the system startup.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
