Network-on-chip (NoC) is currently the chosen paradigm for interconnection in multicore architectures. On the other hand, the development of these architectures with thousands of cores leads to several issues regarding latency and power consumption, especially with conventional wired interconnects. Moreover, they do not support specific features like broadcast and multicast. Radio-Frequency NoC based on OFDMA seems an appropriate solution to overcome such issues, providing low latency for long communications and a significant communication bandwidth with a high spectral efficiency. It also permits a dynamic allocation of the available bandwidth among the different elements of the NoC, according to the communication needs. The routing algorithm has a significant impact on the overall performance of a RF-NoC, by diffusing the traffic in a suitable way between the wired and the wireless paths in order to improve the throughput and reduce the latency. In this paper, a threshold-based routing algorithm is proposed and evaluated for a 32×32 RF-NoC OFDMA architecture with 32 concurrent wireless channels. We demonstrate the importance to finely tune the threshold parameter to achieve a certain level of performance. Simulation results show a significant improvement in terms of latency and throughput.

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The Network-on-chip (NoC) paradigm has been proposed as a promising solution to enable the handling of a high degree of integration in multi-/many-core architectures. Despite their advantages, wired NoC infrastructures are facing several performance issues regarding multi-hop long-distance communications. RF-NoC is an attractive solution offering high performance and multicast/broadcast capabilities. However, managing RF links is a critical aspect that relies on both application-dependent and architectural parameters. This paper proposes a design space exploration framework for OFDMA-based RF-NoC architecture, which takes advantage of both real application benchmarks simulated using Sniper and RF-NoC architecture modeled using Noxim. We adopted the proposed framework to finely configure a routing algorithm, working with real traffic, achieving up to 45% of delay reduction, compared to a wired NoC setup in similar conditions.