Lucent Technologies Inc.

Columbia University

Edward Eric Harstead

Wayne Harvey Knox

Paul R Prucnal

Martin C Nuss

Jason Blain Stark

Louis Viktor Hazeu

Stuart Ds Elby

A point-to-multipoint protected network and related equipment for providing protection against fiber and/or interface failures while reducing or eliminating fiber redundancy requirements. The head end is coupled to a ring network comprised of one fiber via a passive splitter which sends the downstream signal out in both the clockwise and counterclockwise directions. Each network terminal is coupled to the ring through an optical circuit comprising a 1:2 optical switch and two passive optical taps. The terminal is coupled to the single terminal side of the 1:2 switch while the two terminals of the double terminal side of the switch are coupled to the ring in opposing directions, i.e., clockwise and counterclockwise, respectively. The two terminals of the double terminal side of the optical switch are each coupled to the ring via a passive optical tap. Other ring and star network embodiments are disclosed.

Protection scheme for single fiber bidirectional passive optical point-to-multipoint network architectures

A unique time slot is assigned to each of a plurality of wavelengths emitted by a single, centralized wavelength division multiplexed optical source to provide a 'bit interleaved' WDM signal. In accordance with an illustrative embodiment of the present invention, the thus-developed bit-interleaved WDM signal is replicated in cascaded stages of amplification and power splitting before data is encoded for respective frequency dependent receivers as, for example, a plurality of passive optical networks. Because the output of the optical source need not be encoded with data for the respective receivers until after many stages of splitting and amplification, a small number of time division multiplexing (TDM) modulators synchronized to the source may be used to deliver data to potentially tens of thousands of subscribers.

Call admission control in cellular networks

A passive fiber optic tap for a single mode optical fiber is disclosed which utilizes cladding modes induced within the fiber by a microbender. The fiber has a symmetrically circular hour glass shaped notch for tapping radiation from the cladding mode and a detector converts light into an electrical signal. Large tapping ratios, low excess loss and structural compatibility with integrated circuity is obtained.

Fiber optic tap

Growing community of inventors

New York, NY, United States of America

Edward Eric Harstead