Minimizing Worst-Case Data Transmission Cycles in Wavelength-Routed Optical NoC through Bandwidth Allocation

With the rapid development of integrated photonic technology, wavelength-routed optical networks-on-chip (WRONoC) is emerging as a high-potential computing architecture due to its low power consumption, high bandwidth, and conflict-free communication advantages. Previous works utilize the multi-resonance properties of the microring resonator (MRR), the key component in WRONoC, to transmit multiple signals on different wavelengths in one transmission path, thereby achieving parallel communication. However, they do not consider the demands of the actual application communication bandwidth. If communications with high bandwidth demands are not allocated with highly parallel transmission paths, they may become the bottleneck of the network, resulting in increased transmission cycles and overall data transmission time. In this work, we propose an optimization strategy that allocates signal wavelengths for each communication based on its actual bandwidth demand to reduce communication time. Specifically, based on the actual bandwidth demands and topology structure, we first map the communication nodes in the target application to the ports of a WRONoC topology. Next, we optimize the radii of MRRs in the topology and allocate the signal wavelengths to each transmission path to minimize the worst-case data transmission cycle. Experimental results show that, compared to methods that only consider communication parallelism, our strategy can reduce the worst-case of data transmission cycles by over five times, thereby significantly decreasing the time required for data transmission.