Synchronizing clocks across a communication link

US7907640B2 · kind B2 · utility

Assignee

• Wi-LAN Inc. · CA

Inventors

• Pranesh Sinha · San Diego, US
• Sharon Akler · Kfar Sava, IL
• Yair Bourlas · San Diego, US
• Timothy Gallagher · Encinitas, US
• Sheldon L. Gilbert · San Diego, US
• Stephen C. Pollmann · Santee, US
• Frederick W. Price · Carlsbad, US
• Blaine C. Readler · Sterling, US
• John Wiss · Carlsbad, US
• Eli Arviv · Lod, IL

Key dates

• Filing date: Jul 23, 2009
• Grant date: Mar 15, 2011
• Expiry date: Jul 23, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04W84/20
• WIPO field: Digital communication
• WIPO sector: Electrical engineering

Abstract

A slave clock may be synchronized to a master clock by means of a synchronization signal sent from the master to the slave clock side of the link. The synchronization signal may be an expected signal pattern sent at intervals expected by the slave side. The slave clock may correlate received signals with a representation of the expected synchronization signal to produce a correlation sample sequence at a first sample rate which is related as n times the slave clock rate. A best interpolation may in turn be further refined by estimating between interpolator outputs adjacent to the best interpolation output. The synchronization signal receipt time thus determined is compared to the expected time based upon the slave clock, which is adjusted until the times match. The best interpolation may in turn be further refined by estimating between interpolator outputs adjacent to the best interpolation output.