On-Fly-TOD: an efficient mechanism for crosstalk fault reduction in WNoC

Hierarchical architecture of Wireless Network on Chips (WNoCs) composes of wired level and wireless level. In this architecture, subnetworks in wired level are connected by wireless. One of the main reliability challenges in the wired level of WNoC architecture is the crosstalk fault. Crosstalk fault occurs among the long and adjacent wires of wired level of WNoC due to tandem data traversal. Triple Opposite Directions (TODs) patterns are the worst data traversal patterns that impose the highest intensity effects on wires. To solve this problem, this paper presents a mechanism called On-Fly-TOD. In the architecture of the proposed mechanism, subnetworks are not only connected by a wireless level, but also by wired levels. In other words, this architecture uses the inherent characteristic of WNoCs by sending packets with TOD patterns by the wireless level. In this mechanism, tandem flits are counted and flits with high amounts of TODs are sent using wireless level. Simulations show that On-Fly-TOD mechanism provides a trade-off between performance, power consumption and reliability issues. In addition, this architecture suitably scales with the ever-increasing number of on-chip processing elements (PEs) which guarantees a minimum number of hop counts between any source and destination without using long wires as the number of on-chip PEs increases.