A MAC Controller Design for Zigbee and WiFi Hybrid Network Based on FPGA

There are lots of wireless technologies in IoT networks with different protocols for various scenarios. For example, the devices with either Zigbee or WiFi generally coexists in smart home and their connection is needed sometimes, and a convergence gateway is therefore desired. In this paper, we propose a multi-mode MAC-layer controller supporting IEEE 802.15.4-2003 and IEEE 802.11b based on FPGA, where the frame processing are implemented by hardware. The MAC controller supports the priority-based flow control and the dynamic channel access opportunity adjustment according to priority and channel state. These functions can be configured by the processor on chip. We add the priority subfield to the MAC frame of the MAC controller. To avoid the interference between Zigbee and WiFi channels, the controller builds data path for either of them according to the frame type to be transmitted. The main modules/components of the controller includes the frame encapsulation, transmission, receiving and filtering, the CSMA/CA algorithm, the CRC check, the automatic acknowledgement transmission and the automatic frame retransmission function. The controller is functionally simulated on Xilinx xc7z020 FPGA chip using Vivado Simulator.