Formal Analysis of Crosstalk Noise in Mesh-Based Optical Networks-on-Chip with WDM
Optical networks-on-chip (ONoCs) using wavelength division multiplexing (WDM) technology is one of the most promising candidates in tacking multichannel communication on the single waveguide in multicore systems-on-chip. However, compared to the traditional ONoCs with single wavelength transmitting, ONoCs employing WDM can be more susceptible to the influence of the crosstalk noise, especially the nonlinear noise generated by the four-wave mixing (FWM) effect. Consequently, the crosstalk noise can result in the signal distortion and performance degradation, even constrain the scalability of the WDM-based ONoCs. In this paper, a formal systematical analysis model including the crosstalk noise and optical signal-to-noise ratio (OSNR) analysis in mesh-based ONoCs using WDM is presented at device, router, and network levels. To demonstrate the feasibility of the proposed method, we exploit a numerical simulation example of mesh-based ONoCs using the optimized crossbar and Crux optical routers with eight optical wavelengths. The simulation results show that the crosstalk noise is the critical element for the OSNR diminution and the scalability constraint of the mesh-based ONoCs using WDM. For example, the input power is 0 dBm in the worst case, when the mesh-based WDM-based ONoCs size using optimized crossbar is 4 × 4, the average FWM noise power, linear noise power, and OSNR are -37.61 dBm, -38.86 dBm, and 4.26 dB, respectively, and these values are -37.78 dBm, -38.95 dBm, and -13.65 dB when the scale of network is 6 × 6.