For different distance requirement of LED control system, a Gigabit Ethernet media converter between twisted pair and fiber optic was designed. Ethernet standards 802. 3ab and 802. 3z were introduced. Taking 1000BASE-T and 1000BASE-LX as an example, signal transmission characteristics on the two physical layers was studied in details which were regarded as a basis for building the system structure. By analyzing the transmission frame structure, master FPGA controller was designed for data storing and forwarding. Data frame unpacking and reconstruction were also realized in the controller. The result showed that the system design matched the Ethernet standard on physical layer. The effective transmission rate was up to 2 Gbit/s both in twisted pare and optic fiber. The transmission distance could be 100 m~10 km. With two kinds of medium used in LED transmission system, the highest price quality could be achieved when constructing the network. The design could be a reference for long-distance, real-time, general video transmission besides the LED display.%针对LED控制系统传输距离不同的需求,设计了千兆以太网双绞线、光纤介质转换器.对以太网标准802.3ab和802.3z进行了介绍,以1000BASE-T和1000BASE-LX为例,详细研究了信号在两种标准物理层上的传输特性,并构建了系统结构；对传输帧结构进行了分析,设计了主控FPGA内部的数据存储与转发方案,实现了对数据帧的解包和重建.试验结果表明:系统设计符合以太网标准物理层结构,双绞线、光纤有效传输速率均可达2 Gbit/s,传输距离为100m～10 km.将两种传输介质应用于LED传输系统,可以达到建网的最高性价比；该设计对LED大屏传输系统以外的一般视频的实时远距离传输均有实际的借鉴意义.
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