Chip-Scale Photonic Architectures using Wavelength-Selective Spatial Routing for High-Performance Interconnection Networks

Modern chip-scale computing system performance is increasingly becoming determined by the characteristics of the interconnection network. Photonic technology has been proposed as an alternative to traditional electronic interconnects for its advantages in bandwidth density, latency, and power efficiency. Circuit-switched photonic network architectures take advantage of the optical spectrum to create high-bandwidth transmission links through the transmission of data channels on multiple parallel wavelengths. However, this technique suffers from low path diversity and high setup-time overhead, which consequentially induces high network resource contention and long latencies. This work improves upon the circuit-switching paradigm by introducing the use of wavelength-selective spatial routing to produce multiple logical communication layers on a single physical photonic plane. With a photonic system leveraging 120 wavelength channels, this technique is shown in simulation to achieve as much as 169% and 764% saturation bandwidth improvement over the previous photonic circuit-switching design and the electronic mesh, respectively.