Patents by Inventor Sridhar Kanamaluru

Sridhar Kanamaluru 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).

  • Patent number: 6965784
    Abstract: A compact lightweight antenna for receiving microwave direct line of sight wireless data signals used in services such as Local Multipoint Distribution Services (LMDS). The antenna provides for precise control over isolation of polarized signals. The antenna consists of an external parabolically shaped dome formed of a suitably resilient material such as thermoplastic. A polarizing conductive grating is formed on the interior surface of the dome and serves as a transreflector for initially passing received radiation having a vertical polarization. A twist reflector disposed at a point along an axis defined by the conductive grating reflects the received radiation, back in the direction of the transreflector with a different polarization. The now differently polarized energy is reflected by the parabolically shaped conductive grating at a feed point located in the center of the twist plate.
    Type: Grant
    Filed: February 21, 2002
    Date of Patent: November 15, 2005
    Assignee: YDI Wireless, Inc.
    Inventors: Sridhar Kanamaluru, Kenneth R. Wood
  • Patent number: 6727776
    Abstract: A device for efficient propagation of radio frequency (RF) signals, including concurrent transmission of signals of different polarizations, includes a waveguide having an input port for receiving electromagnetic radiation having a first polarized signal and a second polarized signal, the first and second polarized signals being orthogonal to one another. The waveguide includes first and second substrates mounted therein and positioned transverse to the longitudinal axis thereof. Both the first and second substrates are substantially transmissive of the electromagnetic radiation. The first substrate includes a probe formed thereon for transmitting or receiving the first polarized signal, and the second substrate includes a probe for transmitting or receiving a second polarized signal. A grid substrate is mounted in the waveguide between the first and second substrates and positioned transverse to the longitudinal axis thereof.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: April 27, 2004
    Assignee: Sarnoff Corporation
    Inventor: Sridhar Kanamaluru
  • Patent number: 6621468
    Abstract: A radio frequency (RF) power distribution network includes a block assembly having integrated therein a network of waveguides and a plurality of waveguide power dividers. The block assembly has an input waveguide and N output waveguides. The waveguides and waveguide power dividers form a waveguide network for dividing the power of an RF signal present at the input waveguide among the N output waveguides. The RF distribution network can be adapted for use as a feed network for phased array antenna systems.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: September 16, 2003
    Assignee: Sarnoff Corporation
    Inventor: Sridhar Kanamaluru
  • Patent number: 6597327
    Abstract: A reconfigurable adaptive wideband antenna includes a reconfigurable conductive substrate for dynamic reconfigurablility of the frequency, polarization, bandwidth, number of beams and their spatial directions, and the shape of the radiation pattern. The antenna is configured as a reflect array antenna having a single broadband feed. Reflective elements are electronically painted on the reconfigurable conductive surface using plasma injection of carriers in high-resistivity semiconductors.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: July 22, 2003
    Assignee: Sarnoff Corporation
    Inventors: Sridhar Kanamaluru, Aly E. Fathy, Ayre Rosen
  • Patent number: 6567046
    Abstract: A reconfigurable antenna capable of dynamic reconfigurability of several antenna parameters. Specifically, the present invention is an antenna comprising a plurality of surface PIN devices arranged in a gridlike array. Each of the SPIN devices can be individually activated or deactivated. When a SPIN device is activated, the surface of the device is injected with carriers such that a plasma is produced within the intrinsic region of the device. The plasma can be sufficiently conductive to produce conductor or metal like characteristics at the surface of the device. Various ones of the SPIN devices can be activated to electronically paint a conductive pattern upon the substrate supporting the PIN devices. Through selective activation of the SPIN devices various surface antenna patterns can be produced upon the substrate including dipoles, cross dipoles, loop antennas, Yagi-Uda type antennas, log periodic antennas, and the like.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: May 20, 2003
    Assignee: Sarnoff Corporation
    Inventors: Gordon C. Taylor, Stewart M. Perlow, Arye Rosen, Aly E. Fathy, Sridhar Kanamaluru, Moniem Esherbiny
  • Publication number: 20030068974
    Abstract: A method and system for delivering personalized, location-sensitive information to a user device comprising an information network interface for collecting, filtering and storing information and a broadcast network for delivering, as broadcast information, some or all of the collected information to a user device. The user device filters the broadcast information in accordance with a user's personal preferences and a user's location.
    Type: Application
    Filed: April 3, 2001
    Publication date: April 10, 2003
    Applicant: Sarnoff Corporation
    Inventors: Sridhar Kanamaluru, John Riganati, Zygmond Turski, Raymond Camisa
  • Patent number: 6529166
    Abstract: An ultra-wideband, multi-beam adaptive antenna includes a phased array system having an ultra-wideband antenna. The antenna further includes at least two sub-arrays of antenna elements for receiving radio frequency (RF) signals located in a respective at least two sub-bands of a desired wide frequency band. The sub-arrays are interspersed to provide a single wideband antenna, which is coupled with a phased array system having multiple beamforming networks.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: March 4, 2003
    Assignee: Sarnoff Corporation
    Inventor: Sridhar Kanamaluru
  • Publication number: 20030017853
    Abstract: A method and apparatus for enhancing the data transmission capacity of a wireless communication system includes a smart antenna array for forming a radiation pattern to communicate with a plurality of mobile devices and control circuitry for adaptively modifying the radiation pattern to increase the carrier-to-interference (C/I) ratio of the wireless communication system.
    Type: Application
    Filed: July 12, 2002
    Publication date: January 23, 2003
    Applicant: SARNOFF CORPORATION
    Inventors: Sridhar Kanamaluru, Zygmond Turski, Henry Owen
  • Publication number: 20020173342
    Abstract: A compact lightweight antenna for receiving microwave direct line of sight wireless data signals used in services such as Local Multipoint Distribution Services (LMDS). The antenna provides for precise control over isolation of polarized signals. The antenna consists of an external parabolically shaped dome formed of a suitably resilient material such as thermoplastic. A polarizing conductive grating is formed on the interior surface of the dome and serves as a transreflector for initially passing received radiation having a vertical polarization. A twist reflector disposed at a point along an axis defined by the conductive grating reflects the received radiation, back in the direction of the transreflector with a different polarization. The now differently polarized energy is reflected by the parabolically shaped conductive grating at a feed point located in the center of the twist plate.
    Type: Application
    Filed: February 21, 2002
    Publication date: November 21, 2002
    Applicant: Telaxis Communications Corporation
    Inventors: Sridhar Kanamaluru, Kenneth R. Wood
  • Publication number: 20020140616
    Abstract: An ultra-wideband, multi-beam adaptive antenna includes a phased array system having an ultra-wideband antenna. The antenna further includes at least two sub-arrays of antenna elements for receiving radio frequency (RF) signals located in a respective at least two sub-bands of a desired wide frequency band. The sub-arrays are interspersed to provide a single wideband antenna, which is coupled with a phased array system having multiple beamforming networks.
    Type: Application
    Filed: March 27, 2001
    Publication date: October 3, 2002
    Inventor: Sridhar Kanamaluru
  • Publication number: 20020135526
    Abstract: A radio frequency (RF) power distribution network includes a block assembly having integrated therein a network of waveguides and a plurality of waveguide power dividers. The block assembly has an input waveguide and N output waveguides. The waveguides and waveguide power dividers form a waveguide network for dividing the power of an RF signal present at the input waveguide among the N output waveguides. The RF distribution network can be adapted for use as a feed network for phased array antenna systems.
    Type: Application
    Filed: March 26, 2001
    Publication date: September 26, 2002
    Applicant: Sarnoff Corporation
    Inventor: Sridhar Kanamaluru
  • Publication number: 20020109558
    Abstract: A device for efficient propagation of radio frequency (RF) signals, including concurrent transmission of signals of different polarizations, includes a waveguide having an input port for receiving electromagnetic radiation having a first polarized signal and a second polarized signal, the first and second polarized signals being orthogonal to one another. The waveguide includes first and second substrates mounted therein and positioned transverse to the longitudinal axis thereof. Both the first and second substrates are substantially transmissive of the electromagnetic radiation. The first substrate includes a probe formed thereon for transmitting or receiving the first polarized signal, and the second substrate includes a probe for transmitting or receiving a second polarized signal. A grid substrate is mounted in the waveguide between the first and second substrates and positioned transverse to the longitudinal axis thereof.
    Type: Application
    Filed: February 7, 2002
    Publication date: August 15, 2002
    Applicant: Sarnoff Corporation
    Inventor: Sridhar Kanamaluru
  • Publication number: 20020101391
    Abstract: A reconfigurable adaptive wideband antenna includes a reconfigurable conductive substrate for dynamic reconfigurablility of the frequency, polarization, bandwidth, number of beams and their spatial directions, and the shape of the radiation pattern. The antenna is configured as a reflect array antenna having a single broadband feed. Reflective elements are electronically painted on the reconfigurable conductive surface using plasma injection of carriers in high-resistivity semiconductors.
    Type: Application
    Filed: January 26, 2001
    Publication date: August 1, 2002
    Applicant: Sarnoff Corporation
    Inventors: Sridhar Kanamaluru, Aly E. Fathy, Ayre Rosen
  • Patent number: 6370398
    Abstract: A compact lightweight antenna for receiving microwave direct line of sight wireless data signals used in services such as Local Multipoint Distribution Services (LMDS). The antenna provides for precise control over isolation of polarized signals. The antenna consists of an external parabolically shaped dome formed of a suitably resilient material such as thermoplastic. A polarizing metal grid is formed on the interior surface of the dome and serves as a transreflector for initially passing received radiation having a vertical polarization. A twist reflector disposed at a point along an axis defined by the metal grid reflects the received radiation, back in the direction of the transreflector with a different polarization. The now differently polarized energy is reflected by the parabolically shaped metal grid at a feed point located in the center of the twist plate. Operation for transmitting energy is analogous.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: April 9, 2002
    Assignee: Telaxis Communications Corporation
    Inventors: Sridhar Kanamaluru, Kenneth R. Wood
  • Publication number: 20020039083
    Abstract: A reconfigurable antenna capable of dynamic reconfigurability of several antenna parameters. Specifically, the present invention is an antenna comprising a plurality of surface PIN devices arranged in a gridlike array. Each of the SPIN devices can be individually activated or deactivated. When a SPIN device is activated, the surface of the device is injected with carriers such that a plasma is produced within the intrinsic region of the device. The plasma can be sufficiently conductive to produce conductor or metal like characteristics at the surface of the device. Various ones of the SPIN devices can be activated to electronically paint a conductive pattern upon the substrate supporting the PIN devices. Through selective activation of the SPIN devices various surface antenna patterns can be produced upon the substrate including dipoles, cross dipoles, loop antennas, Yagi-Uda type antennas, log periodic antennas, and the like.
    Type: Application
    Filed: March 20, 2001
    Publication date: April 4, 2002
    Inventors: Gordon C. Taylor, Stewart M. Perlow, Arye Rosen, Aly E. Fathy, Sridhar Kanamaluru, Moniem Elsherbiny