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: 20060221864Abstract: 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: ApplicationFiled: March 30, 2005Publication date: October 5, 2006Inventors: Feng Niu, Spyros Kyperountas, Qicai Shi
-
Publication number: 20060181458Abstract: 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: ApplicationFiled: February 14, 2005Publication date: August 17, 2006Inventors: Feng Niu, Spyros Kyperountas, Qicai Shi, David Taubenheim
-
Patent number: 7092726Abstract: 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: GrantFiled: December 29, 2003Date of Patent: August 15, 2006Assignee: Motorola, Inc.Inventors: Qicai Shi, Neiyer S. Correal, Paul E. Gorday, Spyros Kyperountas, Feng Niu
-
Publication number: 20050143100Abstract: 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: ApplicationFiled: December 29, 2003Publication date: June 30, 2005Inventors: Qicai Shi, Neiyer Correal, Paul Gorday, Spyros Kyperountas, Feng Niu
-
Publication number: 20050143101Abstract: 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: ApplicationFiled: December 29, 2003Publication date: June 30, 2005Inventors: Spyros Kyperountas, Oleg Andric, Neiyer Correal, Jian Huang, Feng Niu, Qicai Shi
-
Publication number: 20050134456Abstract: 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: ApplicationFiled: December 23, 2003Publication date: June 23, 2005Inventors: Feng Niu, Spyros Kyperountas, Frederick Martin, Jian Huang, Qicai Shi, Timothy Bancroft, Neiyer Correal
-
Publication number: 20050007963Abstract: 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: ApplicationFiled: July 9, 2003Publication date: January 13, 2005Inventors: Jian Huang, Lance Hester, Yan Huang, Spyros Kyperountas, Feng Niu, Qicai Shi
-
Publication number: 20040246903Abstract: 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: ApplicationFiled: June 4, 2003Publication date: December 9, 2004Inventors: Jian Huang, Feng Niu, Yan Huang, Spyros Kyperountas
-
Publication number: 20040213190Abstract: 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: ApplicationFiled: April 25, 2003Publication date: October 28, 2004Inventors: Spyros Kyperountas, Feng Niu, Qicai Shi
-
Patent number: 6734762Abstract: 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: GrantFiled: April 9, 2001Date of Patent: May 11, 2004Assignee: Motorola, Inc.Inventors: Kenneth D. Cornett, Feng Niu
-
Patent number: 6710680Abstract: 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: GrantFiled: December 20, 2001Date of Patent: March 23, 2004Assignee: Motorola, Inc.Inventors: Feng Niu, Wayne W. Chiou
-
Patent number: 6624726Abstract: 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: GrantFiled: August 31, 2001Date of Patent: September 23, 2003Assignee: Motorola, Inc.Inventors: Feng Niu, Kenneth D. Cornett
-
Patent number: 6605151Abstract: 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: GrantFiled: November 29, 2000Date of Patent: August 12, 2003Assignee: Northwestern UniversityInventors: Bruce W. Wessels, Brent H. Hoerman, Feng Niu
-
Publication number: 20030117237Abstract: 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: ApplicationFiled: December 20, 2001Publication date: June 26, 2003Inventors: Feng Niu, Wayne W. Chiou
-
Publication number: 20030052742Abstract: 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: ApplicationFiled: August 31, 2001Publication date: March 20, 2003Inventors: Feng Niu, Kenneth D. Cornett
-
Publication number: 20020145489Abstract: 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: ApplicationFiled: April 9, 2001Publication date: October 10, 2002Inventors: Kenneth D. Cornett, Feng Niu
-
Patent number: 6445348Abstract: 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: GrantFiled: May 26, 2000Date of Patent: September 3, 2002Assignee: Motorola, Inc.Inventors: Danny O. McCoy, Feng Niu
-
Patent number: 6160515Abstract: 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: GrantFiled: June 1, 1999Date of Patent: December 12, 2000Assignee: Motorola, Inc.Inventors: Danny O. McCoy, Feng Niu
-
Patent number: 5929825Abstract: 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: GrantFiled: March 9, 1998Date of Patent: July 27, 1999Assignee: Motorola, Inc.Inventors: Feng Niu, Wei-Yean Howng, Jon Patrick Oliver
-
Patent number: 5689217Abstract: 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: GrantFiled: March 14, 1996Date of Patent: November 18, 1997Assignee: Motorola, Inc.Inventors: Wang-Chang Albert Gu, Feng Niu