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. 26, 2014
Filed:
Oct. 23, 2008
Peter Healey, Ipswich, GB;
Peter Healey, Ipswich, GB;
British Telecommunications plc, London, GB;
Abstract
This concerns a protected long-reach PON having a plurality of terminals connected to a distribution network that is fed by both a main and back up feed, each feed including a head end and a repeater. The back up head end had access to a ranging table with data previously obtained by the main head end, thereby speeding up the switch over in the event of a fault with the main feed. In one embodiment, the repeater has a virtual ONU therein, allowing the back up repeater to be ranged by the back up head end, thereby yet further speeding up the ranging procedure. The main and back up repeaters are sufficiently equidistant from the distribution network to allow the back up head to perform normal scheduling without performing a ranging operation on each of the terminals, even if the different terminals transmit at slightly different wavelengths. This is achieved using the ranging information obtained with regard to the back up repeater.