The clock recovery module can recover the accurate original clock with the help of digital PLL technology. The queue management module can realize the packet loss and the disorder process. The network timing delay absorbing module is realized with the use of dithering buffer. 其中时钟恢复模块在接收端利用数字锁相环技术恢复出精确的发端时钟,队列管理模块完成了对分组丢失和乱序的处理,而网络时延的吸收是通过抖动缓冲区来完成的。
The design mainly describes the key modules such as the clock recovery module, the queue management module and the network timing delay absorbing module. 该方案重点描述了时钟恢复、队列管理和吸收网络时延等功能的实现。
The high resolution timer system can require microsecond-level clock accuracy based on the OTRC which manage the queue of timer. 该系统基于OTRC对定时器队列的管理,可以得到微秒级的时钟精度。
Two types of communication nodes are designed, one is bus-Ethernet network interface card which has clock synchronization and protocol conversion functions, and the other is train gateway node which provides simple routing and queue scheduling functions. 最后,本文使用ARM系列微处理器和嵌入式操作系统设计了两类列车以太网通信节点:一类是具有时钟同步及协议转换功能的总线-以太网网卡,另一类是具有路由和队列调度功能的车辆网关。
The clock recovery module can recover the accurate original clock with the use of digital PLL technology. The queue management module can realize the packet loss and the disorder process. 时钟恢复模块利用数字锁相环技术恢复出准确的发端时钟,队列管理模块完成对分组丢失和乱序的处理。