Autonomous temperature sensing for optical network-on-chip

Optical network-on-chip (ONoC) architecture is an emerging communication paradigm that upgrades the traditional electronic NoCs with low latency, ultra-high bandwidth, and good scalability. Processor cores on ONoCs often suffer from overheating problems and it is vital to precisely monitor the temperature of every individual core to perform task scheduling, for ensuring system reliability. In this paper, we propose an on-chip temperature sensing technique. It is implemented by utilizing the existing data communications on ONoCs and the thermo-optic effect of nanophotonic devices. Based on the free communication resources on ONoCs, we propose a polynomial-time algorithm to build auxiliary paths. Combined with the existing data communication paths, we can successfully obtain the on-chip temperature distribution without requiring additional hardware support. Simulation results based on a large number of randomly-generated data communications show that our algorithm is applicable and highly efficient over 94% of cases.