The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 17, 2004
Filed:
Feb. 12, 2001
Peter Van Eijk, Eemnes, NL;
Reed K. Even, Livingston, NJ (US);
Piet Van Heyningen, Almere, NL;
Song Jiang, Whippany, NJ (US);
Kyeong-Soo Kim, San Jose, CA (US);
Woojune Kim, Seoul, KR;
Fengkun Liu, Great Neck, NY (US);
Yong-Kwan Park, Annandale, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
An optical network has an optical splitter connected to (1) a working optical subscriber unit (OSU) of a working circuit via a working optical fiber, (2) a protection OSU of a protection circuit via a protection optical fiber, and (3) one or more optical network terminals (ONTs), where the protection OSU has a protection burst mode receiver (BMR) configured to receive an upstream optical signal from the optical splitter. The algorithm determines whether the protection OSU is functioning improperly. A reset pulse is applied at the protection BMR at a particular timing position and an attempt is made to interpret the current upstream cell received at the protection BMR. This process is repeated using different timing positions for the BMR reset pulse until the current upstream cell is correctly interpreted, e.g., based on the correct identification of an ATM header error correction (HEC) byte in the upstream cell. If, after a specified number of cycles, no upstream cells are correctly interpreted, then the protection circuit is determined to have failed. In one embodiment, the algorithm is based on a cell delineation procedure implemented as a state machine.