公开(公告)号：US06298098B1

公开(公告)日：2001-10-02

申请号：US09022467

申请日：1998-02-12

申请人： Norman F. Krasner ,  Allen Ponsford Edwards ,  William G. Xenakis ,  Bruce J. Currivan

发明人： Norman F. Krasner ,  Allen Ponsford Edwards ,  William G. Xenakis ,  Bruce J. Currivan

IPC分类号： H04L2510

CPC分类号： H04L7/046

摘要： A hybrid fiber/coax digital data transmission system in which data from a plurality of subscribers are transmitted upstream to a headend demodulator in a series of data bursts. The headend demodulator acquires and synchronizes a data burst by detecting a BPSK preamble having a repetitive one and zero pattern (10101010101000). The pattern is detected by integrating clock energy in an envelope of a preamble length transmission and using the last three symbols (0,0,0) as a frame marker after differential decoding. Noise in the system is periodically measured by detecting an empty burst placed periodically in the data stream. A first-in, first-out (FIFO) memory allows closer spacing for the data bursts by permitting asynchronous received and output clocks.

摘要翻译： 一种混合光纤/同轴电缆数字数据传输系统，其中来自多个用户的数据在一系列数据突发中向上游发送到头端解调器。 前端解调器通过检测具有重复的一个和零个模式的BPSK前导码（10101010101000）来获取和同步一个数据突发。 通过在前导码长度传输的包络中集成时钟能量并且在差分解码之后使用最后三个符号（0,0,0）作为帧标记来检测模式。 通过检测在数据流中周期性地放置的空脉冲来周期性地测量系统中的噪声。 先进先出（FIFO）存储器通过允许异步接收和输出时钟允许数据突发的更紧密的间隔。