An Efficient and Low Density Crossbar Switch Design for NoC

Abstract

Code Division Multiple Access (CDMA) is a sort of multiplexing that facilitates various signals to occupy a single transmission channel. In this medium, sharing is enabled in the code space by assigning a limited number of N-chip length orthogonal spreading codes to the processing elements sharing interconnect. Serial and parallel overloaded CDMA interconnect (OCI) architecture variants are presented to adhere to different area, delay, and power requirements. Compared with the conventional CDMA crossbar, on a  Xilinx  Artix-7  AC701  FPGA  kit,  the  serial  OCI crossbar achieves 100% higher bandwidth, 31% less resource utilization, and 45% power saving, while the parallel OCI crossbar achieves N times higher  bandwidth  compared with the serial OCI crossbar at the expense of increased area  and power consumption. A 65-node OCI-based star NoC is implemented, evaluated, and compared with an equivalent space division multiple access based torus NoC for various synthetic traffic patterns. The evaluation results in terms of the resource utilization and throughput highlight the OCI as a promising technology to implement the physical layer of NoC routers.