Coherent crosstalk noise analyses in ring-based optical interconnects

Recently, optical interconnects have been proposed for ultra-high bandwidth and low latency inter/intra-chip communication in multiprocessor systems-on-chip (MPSoCs). These optical interconnects employ the microresonators (MRs) to direct/detect the optical signal. However, utilized MRs suffer from intrinsic crosstalk noise and power loss, degrading the network efficiency via the signal-to-noise ratio (SNR). In this paper, both coherent and incoherent crosstalk in wavelength-division multiplexing (WDM) networks are discussed and systematically analyzed. We carefully develop our analytical models at the optical-circuit level, and apply them to two ring-based networks: SUOR and Corona ONoCs. The quantitative results have demonstrated that the architectural design of the ONoCs determines the impact of crosstalk on the SNR. Even though SUOR and Corona are both ring-based ONoCs, the worst-case SNR can be differed up to 50dB. Our analyses of the worst-case SNR can be utilized as a platform to compare the realistic performance among different optical interconnection networks via the degradation of BER and data bandwidth.