Title:
MPEG PROGRAM CLOCK REFERENCE (PCR) DELIVERY FOR SUPPORT OF ACCURATE NETWORK CLOCKS
Document Type and Number:
WIPO Patent Application WO2003026177
Kind Code:
A8
Abstract:
An architecture for providing high-speed access over frequency-division multiplexed (FDM) channels allows transmission of data across a cable transmission network. Downstream packets carrying network clocking may utilize the MPEG packet format, and the clock may be an MPEG program clock reference (PCR). Unlike the common use of the MPEG program clock reference for synchronizing data flowing in the same direction as the clock information, the use of the MPEG program clock reference also is used for synchronizing data flowing an opposite direction to the clock information. Furthermore, the clocking information is used to accurately align frequency channel usage of the remote or client devices (295, 296). Because a plurality of client or remote device (295, 296) may use frequency-division multiplexing, an accurate frequency reference from a network clock helps to ensure that the transmissions of the plurality of client devices (295, 296) do not overlap in frequency.
Inventors:
RITCHIE JOHN A JR
AO JIENING
SORENSON DONALD C
AO JIENING
SORENSON DONALD C
Application Number:
PCT/US2002/029585
Publication Date:
April 22, 2004
Filing Date:
September 18, 2002
Export Citation:
Assignee:
SCIENTIFIC ATLANTA (US)
International Classes:
H04L12/28; H04L12/413; H04L27/26; H04N7/62; H04J3/06; H04L7/04; H04L29/06; (IPC1-7): H04J3/06; H04L7/00
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