Patents by Inventor Naresh Chand

Naresh Chand 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: 20070153772
    Abstract: A method, system and apparatus are provided for measuring the quality of voice (QOV) in a communication network. A time-stamped voice data packet is received. The time stamped on the voice data packet indicates the time at which the voice data packet arrives at intermediate devices. In an embodiment of the invention, the intermediate devices at each hop stamp the time. Thereafter, the voice data packets are analyzed to measure the quality of voice in the communication network.
    Type: Application
    Filed: January 5, 2006
    Publication date: July 5, 2007
    Applicant: Cisco Technology, Inc.
    Inventors: Shiva Shankar J, Ottalingam Satyanarayan, Srinivas Muktevi, Naresh Chand
  • Patent number: 7068936
    Abstract: Methods and apparatus for providing a time slot switch which performs switching in the optical domain without the need for O-E-O conversion is described. The time slot switching device of the present invention may be part of a large switching device capable of performing switching and other function on WDM, TDM and WDM signals which are time division multiplexed. An optical time slot switch implemented using a time slot demultiplexer, optical cross-connect, variable delay lines and time slot multiplexer are described. Frequency conversion may be performed on a per time slot basis in cases where time slot signals are switched between lines using different wavelengths. Wave division demultiplexers and multiplexers can be added to the basic time slot switch to provide support for WDM switching and switching of TDM signals which are transmitted using wave division multiplexing.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: June 27, 2006
    Assignee: Agere Systems Inc.
    Inventors: Stanley Pau, Jianjun Yu, Keisuke Kojima, Naresh Chand
  • Publication number: 20040208555
    Abstract: Methods and apparatus for providing a time slot switch which performs switching in the optical domain without the need for O-E-O conversion is described. The time slot switching device of the present invention may be part of a large switching device capable of performing switching and other function on WDM, TDM and WDM signals which are time division multiplexed. An optical time slot switch implemented using a time slot demultiplexer, optical cross-connect, variable delay lines and time slot multiplexer are described. Frequency conversion may be performed on a per time slot basis in cases where time slot signals are switched between lines using different wavelengths. Wave division demultiplexers and multiplexers can be added to the basic time slot switch to provide support for WDM switching and switching of TDM signals which are transmitted using wave division multiplexing.
    Type: Application
    Filed: June 3, 2002
    Publication date: October 21, 2004
    Inventors: Stanley Pau, Jianjun Yu, Keisuke Kojima, Naresh Chand
  • Publication number: 20040138146
    Abstract: Disclosed are methods of preventing or treating cardiac arrhythmia comprising administering to a mammal in need thereof, such as a human, an effective amount of vanoxerine (GBR 12909) or a pharmaceutically acceptable salt, derivative or metabolite thereof.
    Type: Application
    Filed: December 23, 2003
    Publication date: July 15, 2004
    Applicants: ChanTest, Inc., Government of the United States of America
    Inventors: Arthur M. Brown, Naresh Chand
  • Patent number: 6763193
    Abstract: This invention is a new communication system in which multichannel broadcast digital services are distributed to each user with the broadcast services signal riding in the passband above a digital baseband signal. The system can deliver more than 1 Gbps additional bandwidth to each subscriber. The passband bandwidth will accommodate growth in downstream services including video on demand, higher speed web downloads including improved streaming audio and video, HDTV, interactive video, and personalized video. The invention requires only a single fiber path and a single optical receiver for each user or group of users. A single fiber, single optical receiver system is much less expensive than two systems, one transmitting baseband and the other passband. A single receiver is greatly cost beneficial to achieving economical fiber to the home.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: July 13, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Naresh Chand, Thomas Henry Daugherty, Wouterus Muys, Yong-Kwan Park, Venkataraman Swaminathan
  • Patent number: 6743797
    Abstract: Disclosed are methods of preventing or treating cardiac arrhythmia comprising administering to a mammal in need thereof, such as a human, an effective amount of vanoxerine (GBR 12909) or a pharmaceutically acceptable salt, derivative or metabolite thereof.
    Type: Grant
    Filed: February 22, 2002
    Date of Patent: June 1, 2004
    Assignees: ChanTest, Inc., United States of America
    Inventors: Arthur M. Brown, Naresh Chand
  • Patent number: 6727901
    Abstract: A system generates a smoothed curve from a noisily drawn, multi-segmented curve by minimizing an energy function for a smoothed curve which fits between end-points of the drawn curve. The energy function has three components: a distortion component, a smoothing component and a shrink component. Numerical analysis methods are applied to evaluate the energy function and to identify the smoothed curve with the lowest energy. The transposed curve with the lowest energy value is selected as the smoothed curve.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: April 27, 2004
    Assignee: Adobe Systems Incorporated
    Inventor: Naresh Chand Gupta
  • Publication number: 20030235227
    Abstract: A transmit optical subassembly (TOSA) includes a spot-size-converted (SSC) semiconductor laser coupled to an optical fiber without a lens or isolator. The spot-size-converted semiconductor laser includes an active region and an expander region that expands the spot size of the laser while maintaining efficient active laser performance. The SSC laser is coupled to a submount and passively aligned to an optical fiber positioned within a V-shaped groove formed within the submount. The SSC laser includes a narrow far field advantageous for providing a high coupling efficiency and high quality data transmission. The SSC laser is resistant to back reflection and produces a 1.3 or 1.55 micron optical wavelength and a data rate ranging from 1 to 10 Gbps. The TOSA provides high coupled power due to narrow far field, with potential extra reflection resistance due to absorption and mode transfer losses in coupling reflections through the expander back into the active region.
    Type: Application
    Filed: June 19, 2002
    Publication date: December 25, 2003
    Inventors: Naresh Chand, Julie Eng, Martin Christian Fischer, Philip Anthony Kiely, David J. Klotzkin, Keisuke Kojima, Genji Tohmon, Yan Xu
  • Patent number: 6617288
    Abstract: This invention relates to an aqueous composition comprising water, a surfactant or thickener, and at least one metal-free thiophosphorus acid ester, at least one amine salt of the thiophosphorus acid ester, or a mixture thereof, wherein the thiophosphorus acid ester contains at least one hydrocarbyl terminated oxyalkylene group, at least one hydrocarbyl terminated polyoxyalkylene group, or a mixture thereof. The aqueous compositions have improved antiwear/extreme pressure properties and improved antioxidation properties. In these compositions, the thiophosphorus acid esters and their salts act as antiwear agents and rust inhibitors.
    Type: Grant
    Filed: May 8, 1998
    Date of Patent: September 9, 2003
    Assignee: The Lubrizol Corporation
    Inventors: Naresh Chand Mathur, Edward J. Konzman
  • Publication number: 20030165285
    Abstract: Methods and apparatus for providing improving optical signal transmission results over standard mode fiber using a combination of negative chirp, low extinction ratio, and self-phase modulation transmission techniques in combination are described. The use of pre-transmission signal distortion in combinations with one or more of the other transmission techniques is also described. Pre-transmission signal distortion may be introduced by controlling a modulator with a large symmetric AC signal which causes the modulator to operation in a non-linear region or, alternatively, by using a relatively small non-symmetric AC signal to drive the modulator. Use of the small non-symmetric signal has the advantage of reduced power requirements. The pre-transmission distortion acts to counter some of the distortion introduced by the transmission of the signal over an optic fiber.
    Type: Application
    Filed: August 9, 2002
    Publication date: September 4, 2003
    Inventors: Jianjun Yu, Keisuke Kojima, Naresh Chand
  • Publication number: 20030043431
    Abstract: Simultaneous demultiplexing and clock recovery of high-speed (e.g., 80 Gbps or 160 Gbps) optical time division multiplexing (OTDM) signals is achieved using a tandem electro-absorption modulator (TEAM). The TEAM has a monolithically integrated SOA to compensate the insertion loss and two EAMs to reduce the switching window. The demultiplexing and clock recovery may be performed by a single TEAM, or by two or more TEAMs. A fiber Raman amplifier may be used to boost the intensity of the OTDM signals during transmission.
    Type: Application
    Filed: January 30, 2002
    Publication date: March 6, 2003
    Inventors: Naresh Chand, Keisuke Kojima, Thomas Gordon Beck Mason, Jianjun Yu, Rolando Espindola
  • Publication number: 20030025697
    Abstract: A system generates a smoothed curve from a noisily drawn, multi-segmented curve by minimizing an energy function for a smoothed curve which fits between end-points of the drawn curve. The energy function has three components: a distortion component, a smoothing component and a shrink component. Numerical analysis methods are applied to evaluate the energy function and to identify the smoothed curve with the lowest energy. The transposed curve with the lowest energy value is selected as the smoothed curve.
    Type: Application
    Filed: August 7, 2002
    Publication date: February 6, 2003
    Applicant: Adobe Systems Incorporated, a Delaware Corporation
    Inventor: Naresh Chand Gupta
  • Publication number: 20020163705
    Abstract: An optical transmitter for digitally modulated RF sub-carriers comprising an electroabsorption modulator integrated distributed feedback laser for transmitting the digitally modulated RF sub-carriers in the sub-octave frequency range. The negative bias is optimized for maximum carrier signal to noise ratio (CNR) which occurs when the composite triple beat (CTB) non-linear distortion is minimum that allows higher modulation index without causing any in-band distortion. A higher CNR increases the receiver sensitivity and thus more users can be served from a single transmitter or the transmitting signal can be modulated with higher order of digital modulation.
    Type: Application
    Filed: April 6, 2001
    Publication date: November 7, 2002
    Inventors: Laurens Bakker, Naresh Chand, Doutje Tjitske van Veen
  • Patent number: 6462739
    Abstract: A system generates a smoothed curve from a noisily drawn, multi-segmented curve by minimizing an energy function for a smoothed curve which fits between end-points of the drawn curve. The energy function has three components: a distortion component, a smoothing component and a shrink component. Numerical analysis methods are applied to evaluate the energy function and to identify the smoothed curve with the lowest energy. The transposed curve with the lowest energy value is selected as the smoothed curve.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: October 8, 2002
    Assignee: Abode Systems Incorporated
    Inventor: Naresh Chand Gupta
  • Patent number: 6459521
    Abstract: An optical transmitter for digitally modulated RF sub-carriers comprising an electroabsorption modulator integrated distributed feedback laser for transmitting the digitally modulated RF sub-carriers in the sub-octave frequency range. The negative bias is optimized for maximum carrier signal to noise ratio (CNR) which occurs when the composite triple beat (CTB) non-linear distortion is minimum that allows higher modulation index without causing any in-band distortion. A higher CNR increases the receiver sensitivity and thus more users can be served from a single transmitter or the transmitting signal can be modulated with higher order of digital modulation.
    Type: Grant
    Filed: April 6, 2001
    Date of Patent: October 1, 2002
    Assignee: Agere Systems Guardian Corp.
    Inventors: Laurens Bakker, Naresh Chand, Doutje Tjitske van Veen
  • Patent number: 5968880
    Abstract: This invention relates to a lubricating composition comprising a major amount of an oil of lubricating viscosity and at least one metal-free thiophosphorus acid ester, at least one amine salt of the thiophosphorus acid ester, or a mixture thereof, wherein the thiophosphorus acid ester contains at least one hydrocarbyl terminated oxyalkylene group, at least one hydrocarbyl terminated polyoxyalkylene group, or a mixture thereof. In one embodiment, the thiophosphorus acid ester is a thiophosphorus acid ester represented by the following formula ##STR1## wherein X.sub.1, X.sub.2, and X.sub.3 are oxygen or sulfur, provided that at least one of X.sub.1, X.sub.2, and X.sub.3 is sulfur; R.sub.1 is a hydrocarbyl group; R.sub.2 is an alkylene group; R.sub.3 is hydrogen or a hydrocarbyl group; x is a number from 1 to about 40; and a is 0, 1, or 2, or at least one salt of the thiophosphorus acid ester.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: October 19, 1999
    Assignee: The Lubrizol Corporation
    Inventors: Naresh Chand Mathur, Mary Galic Raguz
  • Patent number: 5773318
    Abstract: The specification describes techniques for cleaving crystal bodies, e.g. semiconductor laser bars, using thermostatic cleaving tools. Use of such tools allows the cleaving process to occur in an ultra high vacuum chamber without the use of mechanical devices activated from the exterior of the chamber. Cleaving occurs automatically and controllably by locally heating the cleaving tools, thereby deflecting the thermostatic element against the laser bar and causing fracture.
    Type: Grant
    Filed: October 30, 1996
    Date of Patent: June 30, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Naresh Chand, Robert Alan Hamm
  • Patent number: 5665637
    Abstract: Provision of a novel passivation layer can result in improved reliability of semiconductor lasers having a laser cavity defined by 2 laser facets. In a preferred embodiment, the passivation layer is a zinc selenide layer (e.g., 5 nm), formed on an essentially contamination-free laser facet. More generally, the passivation layer comprises at least one of Mg, Zn, Cd and Hg, and at least one of S, Se and Te. Typically, the facets are formed by cleaving in vacuum, immediately followed by in-situ deposition of the novel passivation layer material on the facets.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: September 9, 1997
    Assignee: Lucent Technologies Inc.
    Inventor: Naresh Chand
  • Patent number: 5629233
    Abstract: The disclosed novel method of making III/V semiconductor lasers involves cleaving of the wafer along predetermined cleavage planes. A cleavage plane is defined by means of aligned non-continuous depressions. The depressions are spaced from the laser contact regions, and typically are V-grooves produced by photolithography and anisotropic etching. A further surface feature, typically a precisely positioned scribe mark, facilitates cleavage initiation. When carried out in vacuum the novel method can provide high quality, accurately positioned cleavage surfaces, and consequently can facilitate increased yield of high power lasers.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: May 13, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Naresh Chand, Sung-Nee G. Chu, Alexei V. Syrbu
  • Patent number: 5440575
    Abstract: Disclosed are high reliability semiconductor lasers that need not be maintained inside a hermetic enclosure. Such lasers can advantageously be used in a variety of applications, e.g., in optical fiber telecommunications, and in compact disc players. Such "non-hermetic" lasers comprise facet coatings that comprise a dielectric layer that has very low water saturation value. In preferred embodiments this dielectric layer is SiO.sub.x (1.ltoreq.x<2), deposited by a molecular beam method. Deposition conditions are selected to result in a dense material that is largely free of particulates and blisters, and is substantially impermeable to moisture. Among the deposition conditions is substantially normal beam incidence, and a relatively low deposition rate. Deposition is advantageously carried out under relatively high vacuum conditions. A quantitative method of determining the water level in a SiO.sub.x film is disclosed.
    Type: Grant
    Filed: April 6, 1994
    Date of Patent: August 8, 1995
    Assignee: AT&T Corp.
    Inventors: Naresh Chand, Robert B. Comizzoli, John W. Osenbach, Charles B. Roxlo, Won-Tien Tsang