公开(公告)号：US09231752B1

公开(公告)日：2016-01-05

申请号：US14639886

申请日：2015-03-05

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Yan Yan ,  Ali Gokhan Ileri ,  Jianghui Su ,  Dawei Huang ,  Xun Zhang ,  Sifang You

IPC: H04L7/00 ,  H04L7/06

CPC classification number: H04L7/0016 ,  H03L7/0807 ,  H03L7/0814 ,  H04L7/0062 ,  H04L7/033

Abstract: Embodiments include systems and methods for increasing frequency offset tracking in clock data recovery (CDR) systems. For example, in asynchronous clocking environments, the receiver-side clock frequency can be offset from the transmitter-side clock. While traditional CDR systems can handle some amount of offset, they are typically ineffective at accurately adapting the receiver-side clocking to an optimal data sampling rate when the offset is excessive. Embodiments include a CDR frequency offset adaptation loop that generates an adaptation signal, which can be monitored to detect an adaptation error arising from excessive frequency offset. In response to the detecting, an offset seed can be selected and injected into the frequency offset adaptation loop, thereby reinitializing the frequency offset adaptation loop with a less stressful seed.

Abstract translation: 实施例包括用于在时钟数据恢复（CDR）系统中增加频率偏移跟踪的系统和方法。 例如，在异步时钟环境中，接收机侧时钟频率可以偏离发射机侧时钟。 虽然传统的CDR系统可以处理一些偏移量，但是当偏移量过大时，它们通常无效地将接收机侧时钟精确地适配到最佳数据采样率。 实施例包括产生自适应信号的CDR频率偏移适配环路，其可以被监视以检测由过多频率偏移引起的适应误差。 响应于检测，可以选择偏移种子并将其注入到频率偏移适配环路中，从而以较小的压力种子重新初始化频率偏移适配环路。