By Casimer DeCusatis
Anticipation is building fast as we approach this year’s OFC conference, the largest optical communication conference in the world! Don’t forget that the deadline for technical registration is coming up on February 4 so you’ll want to reserve your spot now. Technical content is at the heart of every OFC event, and you’ll find a quick summary of the week’s events in the OFC technical conference brochure. Our social media feeds have been buzzing with all the upcoming news and rumored announcements, so in this blog we’ll take a look at the top three technical session topics currently trending for OFC.
Data Center Networking
This was a hot topic last year, and it’s getting even more attention at the upcoming conference. Data centers worldwide are struggling to deliver more bandwidth density in a cost-effective form factor, which has sparked interest in novel types of fiber and transceivers. Some examples include multicore fibers using space division multiplexing, short-reach high-density optical interconnects, and reduced diameter fiber designs that enable smaller attachments for co-packaged or on-board optics. One enabling technology is hollow-core fibers, which have recently demonstrated temperature-insensitive propagation delay. Other types of hollow-core fibers, based on anti-resonant confinement, have demonstrated useful properties such as ultrashort pulse delivery, low attenuation at mid-infrared wavelengths, and the potential for ultraviolet light propagation.
As intra-data center capacity continues to scale, multi-carrier transmission is emerging as the most cost effective approach. There are market opportunities for dense wavelength division multiplexing (DWDM) and optical switching in this area. Novel approaches such as single carrier, single polarization transmission exceeding 100 Gbit/s between data centers is possible, with the aid of pre-equalization and adaptive filtering. A special panel discussion in the Data Center Summit at OFC will consider the adoption and main similarities or differences in open transport architectures for Inter-Data-Center, Metro and Long-Haul optical networks, including recent innovations that are enabling the so-called “open” optical transport revolution.
High performance computing systems (HPC) are a subset of this category, which is particularly interesting as it pushes the limits of Moore’s Law. OFC features discussions on the architectures of today’s top supercomputers as well as the associated interconnection networking challenges. Future supercomputing and data center system designs may include integrated photonics and advanced packaging techniques. OFC will address the design of these systems, including their power consumption limitations and performance analysis.
It should come as no surprise that the top three trending subjects at OFC are related to each other. The discussion of hyper-scale data centers in our last topic leads naturally into the consideration of new optical interconnect requirements. Short distance, multimode fiber links are of interest for their attractive cost point; technical sessions at OFC will consider the impact of launch conditions, connector effects, and advanced modulation formats.
But this is just one of the key technologies being considered. The deployment of 400G optical links is not far away, and roadmaps leading to 1.6 Tbit/s and beyond are under discussion. New types of pluggable optical transceivers may be required. New multi-lane, silicon photonics devices are being demonstrated with bit error rates lower than those typically achieved using forward error correction. These devices may also help support higher speed Ethernet on modern, high radix switches. Monolithic integration of photonic integrated circuits using material sets such as InP, or Germanium-on-silicon photodiode arrays, may have a role to play in future interconnect design. Many papers at OFC are expected to study fundamental technologies, system designs, and challenges facing next generation optical interconnect development
Digital Signal Processing
Continuing the overlapping interest among our top three technical issues, the use of DSP to augment optical communication has received significant attention lately. Many feel that high speed digital augmentation of optical links is needed to reduce operating expenses and accelerate delivery of new high bandwidth services. For example, DSP might compensate for nonlinear optical transmission. The advent of machine learning has dramatically affected this field, with some researchers proposing the use of learned subcarrier interactions to improve bit error rates in coherent optical communication systems. Many DSP algorithms are being researched, including multiple enhancements to the well-known Kramers-Kronig algorithm. Colorless coherent transmission from laser comb sources in a PON architecture may alleviate the need for expensive wavelength locking techniques. A wide range of signal modulation schemes is being investigated, including QAM, nonbinary PCM, QPSK, PS-PAM-4 and PAM-8, sub-band coherent detection, and much more. Possible applications of these techniques include reducing the cost and complexity of coherent transmission technology to the point where it can be effectively deployed in optical access networks.
The combination of these three trends could enable dramatic improvements in optical system performance, which in turn drives new architectures and applications on a much broader scale. Where else but OFC can you find all of these fascinating topics under one roof? Be sure not to miss the February 4 deadline for registration, and reserve your place among the industry trend setters. If you’re working in any of the three areas discussed in this blog, and would like to talk more about how your research impacts the field, drop me a line on Twitter (@Dr_Casimer) and let’s find some time to chat at this year’s OFC conference.
Posted: 30 January 2019 by
| with 0 comments