3D NoC Based on Statistical Time Division Multiplex

In the system of Network on Chip (NoC), local systems normally adopt bus-based architectures while global networks use packet-based communications. However, since the natural difference between these two architectures is unavoidable, it introduces performance degradation to the overall system when cores in local systems visit global resources. And the situation will be worse in the enviroment of 3D NoC due to its larger network sizes. In this paper, a 3D NoC based on Statistical Time Division Multiplexing (STDM) is proposed. Firstly, a STDM controller is introduced into the local system. Then the network interface is designed using the mechanism of counting and waiting. Finally, the router is optimized for supporting the STDM better. And novel packet formats are designed to reduce the network load and improve the system performance further. In order to demonstrate the efficiency of the novel method, a systemC model is built on system level and experimental results show that the proposed method can reduce network load and transmission delay sharply. In the best condition, the improvement can reach 45% and 20.5% compared with the conventional one. And for real applications, especially for communication-intensive ones, the proposed architecture can also improve the performance a lot.