基于CoaXPress接口的高速串行传输系统设计

CoaXPress是一种新型高速数字图像传输接口标准，适用于各种高速和高带宽图像传输应用。本文设计实现了一种基于CoaXPress接口的高速串行传输系统。针对多路高速串行数据传输、调度、缓存和同步难题，硬件上每个模块设计4路CoaXPress接口，模块以FPGA为核心，采用PCIe3.0×8接口与主控制器进行通信，使用DDR4缓存高速数据；FPGA固件逻辑设计中使用XDMA硬核与主控制器进行通信，使用FDMA完成对DDR4的数据调度，使用GTH收发高速串行数据；采用FIFO缓存同步技术和PXI_TRIG触发总线技术相结合的方法，成功地实现了8个CoaXPress发送模块共32路发送接口之间的同步。最终对CoaXPress接口模块和系统进行了测试，CoaXPress接口的眼图、码速率、误码率、同步精度均满足要求。本文所设计的基于CoaXPress接口的高速串行传输系统工作稳定，性能可靠，已应用于新一代空间飞行器载荷—数传链路测试。

Design of high-speed serial transmission system based on CoaXPress interface

CoaXPress is a new high-speed digital image transmission interface standard suitable for a variety of high-speed and high-bandwidth image transmission applications. In this paper, a high-speed serial transmission system based on CoaXPress interface is designed and implemented. To solve the problem of multi-channel high-speed serial data transmission, scheduling, caching and synchronization, four CoaXPress interfaces are designed for each hardware module. The module is based on FPGA, uses PCIe3.0×8 interface to communicate with the main controller, and uses DDR4 to cache high-speed data. In FPGA firmware logic design, XDMA is used to communicate with the main controller, FDMA is used to complete the data scheduling of DDR4, and GTH is used to send and receive high-speed serial data. Based on the combination of FIFO cache synchronization technology and PXI_TRIG trigger bus technology, the synchronization between 32 transmitting interfaces of 8 CoaXPress transmitting modules is successfully realized. Finally, the CoaXPress interface module and system are tested, and the eye map, code rate, bit error rate and synchronization accuracy of CoaXPress interface meet the requirements. The high-speed serial transmission system based on CoaXPress interface designed in this paper is stable and reliable, and has been applied to the test of load-data transmission link of a new generation of space vehicle.