Patents by Inventor Rajiv Ramaswami

Rajiv Ramaswami has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20170180074
    Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.
    Type: Application
    Filed: March 8, 2017
    Publication date: June 22, 2017
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Publication number: 20160337069
    Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.
    Type: Application
    Filed: April 5, 2016
    Publication date: November 17, 2016
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Publication number: 20150180606
    Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.
    Type: Application
    Filed: March 9, 2015
    Publication date: June 25, 2015
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Patent number: 9014562
    Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: April 21, 2015
    Assignee: Coriant Operations, Inc.
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Patent number: 8971706
    Abstract: Automatic discovery and verification of optical communication links as well as isolation of link failures in an optical communication system.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: March 3, 2015
    Assignee: Rockstar Consortium US LP
    Inventors: Ornan A. Gerstel, Humair Raza, Rajiv Ramaswami, Babu O. Narayanan, Robert Ward, Robert Keys, David Park, Vasant Sahay, Osama Aboul-Magd, Frederic Simard
  • Patent number: 8134939
    Abstract: A ring communication network according to an embodiment of the present invention includes a plurality of nodes in which a single one of the nodes is configured for full channel conversion and the remaining nodes, other than the single node, are configured for no channel conversion. Links with no more than W channels couple the nodes. The ring communication network also may include N nodes and links connecting the nodes for carrying data in W channels such that N?2 log2 W?1 where W is a power of 2. Each of the N nodes includes switches connected such that each channel of a first one of the links adjacent to any one of the N nodes can be switched to no more than W?1 channels of another one of the links adjacent any one node.
    Type: Grant
    Filed: September 9, 2009
    Date of Patent: March 13, 2012
    Assignee: Tellabs Operations, Inc.
    Inventors: Rajiv Ramaswami, Galen H. Sasaki
  • Publication number: 20100054263
    Abstract: A ring communication network according to an embodiment of the present invention includes a plurality of nodes in which a single one of the nodes is configured for full channel conversion and the remaining nodes, other than the single node, are configured for no channel conversion. Links with no more than W channels couple the nodes. The ring communication network also may include N nodes and links connecting the nodes for carrying data in W channels such that N?2 log2 W?1 where W is a power of 2. Each of the N nodes includes switches connected such that each channel of a first one of the links adjacent to any one of the N nodes can be switched to no more than W?1 channels of another one of the links adjacent any one node.
    Type: Application
    Filed: September 9, 2009
    Publication date: March 4, 2010
    Applicant: Tellabs Operations, Inc.
    Inventors: Rajiv Ramaswami, Galen H. Sasaki
  • Patent number: 7606180
    Abstract: A ring communication network according to an embodiment of the present invention includes a plurality of nodes in which a single one of the nodes is configured for full channel conversion and the remaining nodes, other than the single node, are configured for no channel conversion. Links with no more than W channels couple the nodes. The ring communication network may include N nodes and links connecting the nodes for carrying data in W channels such that N?2 log2 W?1, where W is a power of 2. Each of the N nodes includes switches connected such that each channel of a first one of the links adjacent to any one of the N nodes can be switched to no more than W?1 channels of another one of the links adjacent to any one node.
    Type: Grant
    Filed: May 16, 2005
    Date of Patent: October 20, 2009
    Assignee: Tellabs Operations, Inc.
    Inventors: Rajiv Ramaswami, Galen Sasaki
  • Publication number: 20080219666
    Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.
    Type: Application
    Filed: March 5, 2008
    Publication date: September 11, 2008
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Patent number: 7369772
    Abstract: A wavelength division multiplexed optical communication system including a first optical line interface optically coupled to a first transponder and an optical demultiplexer through which the first optical line interface is not optically coupled to the first transponder. The system also includes a second optical line interface and at least one switch. The switch is operable to optically couple the second optical line interface to (a) the first optical line interface through at least the optical demultiplexer, and alternatively (b) the second transponder. A method for an optical add/drop multiplexing system also is provided.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: May 6, 2008
    Assignee: Tellabs Operations, Inc.
    Inventors: Ornan A. Gerstel, Rajiv Ramaswami
  • Publication number: 20070104483
    Abstract: Methods and apparatus for managing an optical network using pilot tones are provided. One method includes selecting an optical path having a plurality of nodes from a database defining an expected optical network. A detected list of pilot tones associated with each node of the selected optical path is generated. An expected list of pilot tones associated with each node of the selected optical path is generated. The detected and expected lists are compared to identify any mismatched nodes.
    Type: Application
    Filed: September 18, 2006
    Publication date: May 10, 2007
    Inventors: John Carrick, Mark Oppenheimer, Rajiv Ramaswami, Ornan Gerstel
  • Patent number: 7123832
    Abstract: Methods and apparatus for managing an optical network using pilot tones are provided. One method includes generating a list of pilot tones contributed by a selected node to each of its target nodes. Network pilot tone sources are re-configured so that a pilot tone source of any optical path incorporating one of the target nodes has a value distinct from the listed pilot tones. The selected node can then be added to the network. Another method includes generating a list including all selected network nodes to be incorporated into a new optical path and nodes adjacent to the selected network nodes. Network pilot tone sources are re-configured until a pilot tone source associated with the new optical path has a pilot tone distinct from that of any listed node. The new optical path can then be added to the network.
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: October 17, 2006
    Assignee: Tellabs Operations, Inc.
    Inventors: John C. Carrick, Mark I. Oppenheimer, Rajiv Ramaswami, Ornan A. Gerstel
  • Patent number: 7072031
    Abstract: Apparatus and methods are disclosed for alignment of an input mirror and an output mirror in a photonic cross-connect.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: July 4, 2006
    Assignee: Nortel Networks, Ltd.
    Inventors: Humair Raza, Robert Ward, Rajiv Ramaswami, Babu Narayanan
  • Publication number: 20060110158
    Abstract: Methods and apparatus for managing an optical network using pilot tones are provided. One method includes generating a list of pilot tones contributed by a selected node to each of its target nodes. Network pilot tone sources are re-configured so that a pilot tone source of any optical path incorporating one of the target nodes has a value distinct from the listed pilot tones. The selected node can then be added to the network. Another method includes generating a list including all selected network nodes to be incorporated into a new optical path and nodes adjacent to the selected network nodes. Network pilot tone sources are re-configured until a pilot tone source associated with the new optical path has a pilot tone distinct from that of any listed node. The new optical path can then be added to the network.
    Type: Application
    Filed: January 10, 2006
    Publication date: May 25, 2006
    Inventors: John Carrick, Mark Oppenheimer, Rajiv Ramaswami, Ornan Gerstel
  • Publication number: 20050286442
    Abstract: A ring communication network comprising a plurality of nodes in which a single one of the nodes is configured for full channel conversion and the remaining nodes, other than the single node, are configured for no channel conversion. Links comprising no more than W channels couple the nodes. The ring communication network also may comprise N nodes and links coupling the nodes for carrying data in W channels such that N?2 log2 W?1 where W is a power of 2. Each of the N nodes comprises switches connected such that each channel of a first one of the links adjacent any one of the N nodes can be switched to no more than W?1 channels of another one of the links adjacent any one node.
    Type: Application
    Filed: May 16, 2005
    Publication date: December 29, 2005
    Inventors: Rajiv Ramaswami, Galen Sasaki
  • Patent number: 6970433
    Abstract: A star communication network including a hub node (102) and links (102E) couple to the hub node for carrying data along routes in W channels. The hub node has switches connecting each channel of a first one of the links to various channels of a second one of the links through the hub node.
    Type: Grant
    Filed: July 21, 1999
    Date of Patent: November 29, 2005
    Assignee: Tellabs Operations, Inc.
    Inventors: Rajiv Ramaswami, Galen Sasaki
  • Patent number: 6961506
    Abstract: One aspect is a method for controllably attenuating the beam of light (108) coupled between incoming and outgoing optical fibers (106) by misaligning minor surfaces (116a, 116b) included of an optical switching module (100). Misalignment of the mirror surfaces (116a and 116b) causes only a portion of the beam of light (108) propagating along the incoming optical fiber (106), which is less than when the light beam deflectors' mirror surfaces (116) are precisely aligned, to propagate along the outgoing optical fiber (108). Thus, the optical switching module (100) controllably attenuates the beam of light (108) coupled between the incoming and the outgoing optical fibers (106). Another aspect is a variable-optical-attenuator (“VOA”) (212) that includes an optically reflective membrane (222) upon which the beam of light (108) impinges. Application of an electrostatic field between an adjacent electrode (228) and the membrane (222) deforms the membrane (222) thereby attenuating an impinging beam of light (108).
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: November 1, 2005
    Inventors: Armand P. Neukermans, Rajiv Ramaswami, John F. Heanue, Brian P. Tremaine, Marc Schuman
  • Patent number: 6947623
    Abstract: Methods, apparatus and systems for regenerating, monitoring and bridging optical signals through an optical cross-connect switch to provide increased reliability. A self testing method, apparatus and system for an optical cross-connect switch. An optical-to-electrical-to-optical converter (O/E/O) is provided in an optical cross-connect switch to provide optical-electrical-optical conversion. I/O port cards having an optical-to-electrical-to-optical converter are referred to as smart port cards while I/O port cards without an optical-to-electrical-to-optical converter are referred to as passive port cards. Test port/monitor cards are also provided for testing optical cross-connect switches. Methods, apparatus and systems for performing bridging, test access, and supporting redundant optical switch fabrics are also disclosed.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: September 20, 2005
    Assignee: Nortel Networks Limited
    Inventors: Rajiv Ramaswami, Robert R. Ward
  • Patent number: 6944364
    Abstract: Methods, apparatus and systems for regenerating, monitoring and bridging optical signals through an optical cross-connect switch to provide increased reliability. A self testing method, apparatus and system for an optical cross-connect switch. An optical-to-electrical-to-optical converter (O/E/O) is provided in an optical cross-connect switch to provide optical-electrical-optical conversion. I/O port cards having an optical-to-electrical-to-optical converter are referred to as smart port cards while I/O port cards without an optical-to-electrical-to-optical converter are referred to as passive port cards. Test port/monitor cards are also provided for testing optical cross-connect switches. Methods, apparatus and systems for performing bridging, test access, and supporting redundant optical switch fabrics are also disclosed.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: September 13, 2005
    Assignee: Nortel Networks Limited
    Inventors: Rajiv Ramaswami, Robert R. Ward
  • Patent number: 6882765
    Abstract: The present invention provides methods, apparatus and systems for protecting connections between optical cross-connect switches and client equipment. A connection failure is detected, signaled, and a switch made by the client equipment and the optical cross-connect switch to a protection connection between them so as to minimize service interruption. An out-of-band channel or an in-band channel can be used to signal the connection failure.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: April 19, 2005
    Assignee: XROS, Inc.
    Inventors: Kent Erickson, Subhashini Kaligotia, Rajiv Ramaswami