Robin Jdb Moran

US Patent:

55109179, Apr 23, 1996

Filed:

Apr 4, 1995

Appl. No.:

8/417461

Inventors:

Michael Corke - Mendon MA
Dean A. Werthman - Uxbridge MA
Robin M. Moran - Framingham MA
David W. Stowe - Medfield MA
Neville J. Ronan - Killaloe, IE
Amy R. Beaudet - Manchaug MA

Assignee:

Aster Products - Hopkinton MA

International Classification:

H04B 1008
H04J 1402

US Classification:

359110

Abstract:

For communicating over optical routes, route monitoring and protection are provided. In routes carrying signals on each of a number of wave lengths a tapped fraction of the signal is demultiplexed and an individual wave length is detected for determining performance and for triggering switching to alternative monitored routes carrying the same signal. Switching of all wave lengths if one shows faulty, with either a single wave length or all wave lengths being monitored is shown. Performance of a long wave length component is employed to determine route quality for shorter wave lengths as well. In bi-directional communication systems, performance of a wave length moving in one direction through a route determines route quality for transmission in the other direction, as well. Progressive sampling and digitization of the tapped signal and comparison to a digitized reference enables high sensitivity of monitoring. Detected average intensity of a tapped wave length, detected error rate in tapped wave lengths and use of performance data fed back from the receiver telecommunication equipment are used to control switching from one monitored route to another.