Patents by Inventor Feng Niu

Feng Niu 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: 20060221864
    Abstract: A method and apparatus for determining a best technique (algorithm and/or parameters) to use when locating a node (104) is provided herein. In particular, reference nodes (105) are provided that not only know their own locations, but also test various algorithms and parameters by estimating their locations as if they were blind nodes. The reference nodes then evaluates these various techniques against the user defined criteria for the best technique. Recommendations as to the best technique to utilize are then made to other nodes within the system.
    Type: Application
    Filed: March 30, 2005
    Publication date: October 5, 2006
    Inventors: Feng Niu, Spyros Kyperountas, Qicai Shi
  • Publication number: 20060181458
    Abstract: A method and apparatus for determining the location of a node within a communication system is provided herein. During operation, reference nodes (105) having known locations are utilized to locate “blind” nodes (104) whose location is to be determined. More particularly, a blind node (104) wishing to determine its location will measure a plurality of path losses between itself and a plurality of reference nodes (105). These reference nodes' locations will then be mathematically weighted by the path loss between these reference nodes (105) and the blind node (104). The location of the blind node (104) is a sum of the mathematically weighted reference nodes' locations.
    Type: Application
    Filed: February 14, 2005
    Publication date: August 17, 2006
    Inventors: Feng Niu, Spyros Kyperountas, Qicai Shi, David Taubenheim
  • Patent number: 7092726
    Abstract: A method and system is provided for determining a location for each of a plurality of units, which is selected from one of multiple sets of locations, which are each estimated based upon different initial location estimates. The selected set of locations includes the set which has the minimum error value, where the error value is based on the aggregate of the differences between the range determined from the estimated locations and the measured range. By using different sets of initial location estimates, there is a greater chance that at least one of the sets of initial location estimates will avoid any local minimums and produce a more accurate estimate of unit locations.
    Type: Grant
    Filed: December 29, 2003
    Date of Patent: August 15, 2006
    Assignee: Motorola, Inc.
    Inventors: Qicai Shi, Neiyer S. Correal, Paul E. Gorday, Spyros Kyperountas, Feng Niu
  • Publication number: 20050143100
    Abstract: A method and system is provided for determining a location for each of a plurality of units, which is selected from one of multiple sets of locations, which are each estimated based upon different initial location estimates. The selected set of locations includes the set which has the minimum error value, where the error value is based on the aggregate of the differences between the range determined from the estimated locations and the measured range. By using different sets of initial location estimates, there is a greater chance that at least one of the sets of initial location estimates will avoid any local minimums and produce a more accurate estimate of unit locations.
    Type: Application
    Filed: December 29, 2003
    Publication date: June 30, 2005
    Inventors: Qicai Shi, Neiyer Correal, Paul Gorday, Spyros Kyperountas, Feng Niu
  • Publication number: 20050143101
    Abstract: A method and system is provided for determining a location for each of a plurality of units, which are sub-divided into more than one sub-net groupings, that each include two or more units. Within each sub-net grouping, measured range information between units within the sub-nets and one or more reference units is gathered in at least a selected one of the units. The selected one of the units then estimates a location for each of the units, which minimizes any error in the measured ranges between the units in each of the corresponding sub-nets.
    Type: Application
    Filed: December 29, 2003
    Publication date: June 30, 2005
    Inventors: Spyros Kyperountas, Oleg Andric, Neiyer Correal, Jian Huang, Feng Niu, Qicai Shi
  • Publication number: 20050134456
    Abstract: A method and location determination module is provided for determining a location of one of a plurality of units using neighbor lists. Each unit is communicatively coupled to at least some of the other plurality of units, where at least some of the plurality of units are reference units, whose locations are known. The units communicate with other nearby units within communication range, to establish neighbor lists. A unit to be located then identifies an aggregate value corresponding to the number of occurrences of the reference units in the neighbor list of the unit to be located and the neighbor lists of each of a group of associated units. The location of the unit to be located is then determined, based upon the known locations of the reference units and the number of identified occurrences of the reference units in the corresponding neighbor lists.
    Type: Application
    Filed: December 23, 2003
    Publication date: June 23, 2005
    Inventors: Feng Niu, Spyros Kyperountas, Frederick Martin, Jian Huang, Qicai Shi, Timothy Bancroft, Neiyer Correal
  • Publication number: 20050007963
    Abstract: A method for peer-to-peer ranging and discovery of a rigid body existing in a scatternet having piconets and nodes includes the steps of defining a node (12) in a piconet (10) to be a piconet controller (PNC) having controller functions, locating a rigid body seed including the node (12), and discovering a rigid body by sequentially downloading controller functions of the piconet controller (12) to at least one border node. Also provided is a communications node including a receiver for receiving communications from other communications nodes in a communications range (R), a transmitter for sending communications to other communications nodes in the communications range (R), a memory storing at least ranging information and a unique identification for describing the node, and a processor connected to the receiver, to the transmitter, and to the memory, the processor being programmed to carry out the method according to the present invention.
    Type: Application
    Filed: July 9, 2003
    Publication date: January 13, 2005
    Inventors: Jian Huang, Lance Hester, Yan Huang, Spyros Kyperountas, Feng Niu, Qicai Shi
  • Publication number: 20040246903
    Abstract: A method for reducing communications in a peer-to-peer wireless network having nodes includes sending an RTS-TOA ranging communication from a first node (N0) in a node group to another node (Nr, I) in the group, receiving the RTS-TOA communication with the second node (Nr, I) and sending a multi-cast CTS-TOA/RTS-TOA ranging communication from the second node (Nr, I) as a reply to the received RTS-TOA communication, and successively and sequentially repeating the multi-cast sending step for each of the nodes. A CTS-TOA message is a reply to the received RTS-TOA message and, simultaneously, is an RTS-TOA ranging communication to a new destination node (J). The method applies for a randomized communications approach when node identifications are not sequenced and to a sequential approach where nodes are sequenced, and also applies to completely connected and multi-hop networks. Also provided is a node for carrying out the method of the present invention.
    Type: Application
    Filed: June 4, 2003
    Publication date: December 9, 2004
    Inventors: Jian Huang, Feng Niu, Yan Huang, Spyros Kyperountas
  • Publication number: 20040213190
    Abstract: A method for locating nodes in a multi-hop sensor network forms a rigid body (RB 1, RB2, RB3) and, from the nodes, utilizes the rigid body to decide if a node is locatable. The method obtains a reduced order model (ROM) of the network by categorizing all of the nodes by location status, grouping them based upon the categorizations, and defining and identifying a rigid body from a group. The method further simplifies determinability of node location by forming the rigid body from the nodes based upon the categorized location status. To locate the nodes, the nodes are separated from one another into subsets dependent upon characteristics (100). Then, groups are formed from one subset (200) and the rigid body is formed from a group (300). The ROM is formed from the rigid body (400) and a location capability of the rigid body is evaluated based upon the ROM (500).
    Type: Application
    Filed: April 25, 2003
    Publication date: October 28, 2004
    Inventors: Spyros Kyperountas, Feng Niu, Qicai Shi
  • Patent number: 6734762
    Abstract: A first type of MEMS resonator adapted to be fabricated on a SOI wafer is provided. A second type of MEMS resonator that is fabricated using deep trench etching and occupies a small area of a semiconductor chip is taught. Overtone versions of the resonators that provide for differential input and output signal coupling are described. In particular resonators suited for differential coupling that are physically symmetric as judged from center points, and support anti-symmetric vibration modes are provided. Such resonators are robust against signal noise caused by jarring. The MEMS resonators taught by the present invention are suitable for replacing crystal oscillators, and allowing oscillators to be integrated on a semiconductor chip. An oscillator using the MEMS resonator is also provided.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: May 11, 2004
    Assignee: Motorola, Inc.
    Inventors: Kenneth D. Cornett, Feng Niu
  • Patent number: 6710680
    Abstract: Torsional hinge support beams (104, 106, 108, 110, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500) that are corrugated, perforated and/or have non-uniform width are provided. The support beams are useful in flexural beam resonators (100, 1600), in which they serve to support the main flexural mode-vibrating beam (102, 1602). The support beams have phase lengths equal to an odd multiple of &pgr;/2, preferably the phase lengths are about equal to &pgr;/2 at the operating frequency of the resonators. Owing to the corrugations, the lengths of the support beams are shorter than comparable solid straight edge support beams. The short lengths of the support beams reduce the overall area occupied by the resonators and allow higher bias voltage to be employed in order to obtain greater electromechanical coupling.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: March 23, 2004
    Assignee: Motorola, Inc.
    Inventors: Feng Niu, Wayne W. Chiou
  • Patent number: 6624726
    Abstract: Microelectromechanical resonators that can be fabricated on a semiconductor die by processes normally used in fabricating microelectronics (e.g., CMOS) circuits are provided. The resonators comprises at least two vibratable members that are closely spaced relative to a wavelength associated with their vibrating frequency, and driven to vibrate one-half a vibration period out of phase with each other, i.e. to mirror each others motion. Driving the vibratable members as stated leads to destructive interference effects that suppress leakage of acoustic energy from the vibratable members into the die, and improve the Q-factor of the resonator. Vibratable members in the form of vibratable plates that are formed by deep anisotropic etching one or more trenches in the die are disclosed. Embodiments in which two sets of vibratable plates are spaced by ½ the aforementioned wavelength to further suppress acoustic energy leakage, and improve the Q-factor of the resonator are disclosed.
    Type: Grant
    Filed: August 31, 2001
    Date of Patent: September 23, 2003
    Assignee: Motorola, Inc.
    Inventors: Feng Niu, Kenneth D. Cornett
  • Patent number: 6605151
    Abstract: Thin oxide films are deposited on substrates by metal-organic molecular beam epitaxy (MOMBE) and can be incorporated into a variety of composite materials. The composites/films are characterized by a combination of transmission electron microscopy, Auger spectrometry and atomic force microscopy. Analyzes indicate that the films directly deposited on substrates are stoichiometric and phase-pure. Carbon contamination of the films resulting from precursor decomposition was not observed.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: August 12, 2003
    Assignee: Northwestern University
    Inventors: Bruce W. Wessels, Brent H. Hoerman, Feng Niu
  • Publication number: 20030117237
    Abstract: Torsional hinge support beams (104, 106, 108, 110, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500) that are corrugated, perforated and/or have non-uniform width are provided. The support beams are useful in flexural beam resonators (100, 1600), in which they serve to support the main flexural mode-vibrating beam (102, 1602). The support beams have phase lengths equal to an odd multiple of &pgr;/2, preferably the phase lengths are about equal to &pgr;/2 at the operating frequency of the resonators. Owing to the corrugations, the lengths of the support beams are shorter than comparable solid straight edge support beams. The short lengths of the support beams reduce the overall area occupied by the resonators and allow higher bias voltage to be employed in order to obtain greater electromechanical coupling.
    Type: Application
    Filed: December 20, 2001
    Publication date: June 26, 2003
    Inventors: Feng Niu, Wayne W. Chiou
  • Publication number: 20030052742
    Abstract: Microelectromechanical resonators that can be fabricated on a semiconductor die by processes normally used in fabricating microelectronics (e.g., CMOS) circuits are provided. The resonators comprises at least two vibratable members that are closely spaced relative to a wavelength associated with their vibrating frequency, and driven to vibrate one-half a vibration period out of phase with each other, i.e. to mirror each others motion. Driving the vibratable members as stated leads to destructive interference effects that suppress leakage of acoustic energy from the vibratable members into the die, and improve the Q-factor of the resonator. Vibratable members in the form of vibratable plates that are formed by deep anisotropic etching one or more trenches in the die are disclosed. Embodiments in which two sets of vibratable plates are spaced by ½ the aforementioned wavelength to further suppress acoustic energy leakage, and improve the Q-factor of the resonator are disclosed.
    Type: Application
    Filed: August 31, 2001
    Publication date: March 20, 2003
    Inventors: Feng Niu, Kenneth D. Cornett
  • Publication number: 20020145489
    Abstract: A first type of MEMS resonator adapted to be fabricated on a SOI wafer is provided. A second type of MEMS resonator that is fabricated using deep trench etching and occupies a small area of a semiconductor chip is taught. Overtone versions of the resonators that provide for differential input and output signal coupling are described. In particular resonators suited for differential coupling that are physically symmetric as judged from center points, and support anti-symmetric vibration modes are provided. Such resonators are robust against signal noise caused by jarring. The MEMS resonators taught by the present invention are suitable for replacing crystal oscillators, and allowing oscillators to be integrated on a semiconductor chip. An oscillator using the MEMS resonator is also provided.
    Type: Application
    Filed: April 9, 2001
    Publication date: October 10, 2002
    Inventors: Kenneth D. Cornett, Feng Niu
  • Patent number: 6445348
    Abstract: Dispersive surface antenna structures (300, 700) provide improved selectivity and increased control over bandwidth. Antenna structures (300, 700) include a wraparound piece of conductive material located perpendicular to a ground plane (304, 704). Ground posts (302, 702) extend up from the ground base (304) and capacitively couple to a front conductive surface (301, 701) of the antennas (300, 700). First and second conductive back surfaces (305, 306), (705, 706) are capacitively coupled across a gap (307, 707) along the back of the antennas (300, 700). The size, width, and location of the gap (307, 707) along with the ground posts (302, 702) provide increased control over antenna performance.
    Type: Grant
    Filed: May 26, 2000
    Date of Patent: September 3, 2002
    Assignee: Motorola, Inc.
    Inventors: Danny O. McCoy, Feng Niu
  • Patent number: 6160515
    Abstract: Dispersive surface antenna structures (300, 700) provide improved selectivity and increased control over bandwidth. Antenna structures (300, 700) include a wraparound piece of conductive material located perpendicular to around plane (304, 704). Ground posts (302, 702) extend up from the ground base (304) and capacitively couple to a front conductive surface (301, 701) of the antennas (300, 700). First and second conductive back surfaces (305, 306), (705, 706) are capacitively coupled across a gap (307, 707) along the back of the antennas (300, 700). The size, width, and location of the gap (307, 707) along with the ground posts (302, 702) provide increased control over antenna performance.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: December 12, 2000
    Assignee: Motorola, Inc.
    Inventors: Danny O. McCoy, Feng Niu
  • Patent number: 5929825
    Abstract: A spiral antenna (100) having a feed-point end and a termination end for use within a portable two-way radio housing includes a ground substrate (102) and a number of spiral elements (103, 105) having a number of segments that form two or more spiral shapes. A shorting stub (107) connects the planar elements at a termination end for effectively increasing the feed-point impedance of the spiral antenna (100). The spiral elements (103, 105) may be positioned in a planar arrangement (FIGS. 1 and 2) or may be stacked in separate planes (FIGS. 3 and 4) for forming a limited space antenna having a substantially 50 ohm feed-point end impedance at resonance.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: July 27, 1999
    Assignee: Motorola, Inc.
    Inventors: Feng Niu, Wei-Yean Howng, Jon Patrick Oliver
  • Patent number: 5689217
    Abstract: A multi-layer substrate (500) includes a segmented stripline (602) which is formed of multi-layered segment (514, 522, 516) and is proximately coupled to a second stripline (604) to form a directional coupler. The directional coupler (500) provides similar input and output port impedances while allowing for independent control of the coupling. The overall length of the coupler is held constant while individual lengths of the segments of the segmented stripline (602) and the second stripline (604) are increased and decreased to independently control the coupling while maintaining the similar port impedances.
    Type: Grant
    Filed: March 14, 1996
    Date of Patent: November 18, 1997
    Assignee: Motorola, Inc.
    Inventors: Wang-Chang Albert Gu, Feng Niu