Patents by Inventor Chunjie Duan

Chunjie Duan 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: 8428165
    Abstract: A method estimates a wireless channel at a receiver. The signal is transmitted using narrowband orthogonal frequency division demultiplexing (OFDM) and frequency subcarriers, and the signal includes a set of data tones and a set of pilot tones. The channel and pilot tone interference are estimated based on all the pilot tones extracted from the signal and a channel model. The set of data are equalized based on the channel estimate. Data interference is detected according to the pilot interference and the equalized data tones. Subcarrier interference-to-noise ratios are determined based on the data interference. Signal strengths of the data tones are determined based on the equalized data tones, log-likelihood ratios of bits represented by the data tones are determined based on the subcarrier interference-to-noise ratios and the signal strength of the data tones.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: April 23, 2013
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Raymond Yim, Amitav Mukherjee, Philip V. Orlik, Chunjie Duan, Jinyun Zhang
  • Patent number: 8418813
    Abstract: In a network for a safety system in a transportation system, the transportation system includes a shaft and a car arranged in the shaft. A first wall node is at a first end of the shaft and a second wall node is at a second end of the shaft to communicate safety messages with the car. Each wall node includes at least one wireless transceiver connected to one or more antennas. Each car in the shaft includes at least two wireless transceiver connected to one or more antennas, wherein the first transceiver of the car uses a first frequency and the second transceiver of the car uses a second frequency to communicate each safety messages in duplicate. A wired backbone connects the set of wall nodes to a controller of the safety system of the transportation system.
    Type: Grant
    Filed: November 19, 2010
    Date of Patent: April 16, 2013
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Raymond Yim, Philip V. Orlik, Chunjie Duan, Jinyun Zhang, Jianlin Guo, Frederick J Igo, Jr.
  • Patent number: 8415833
    Abstract: Embodiments of the invention disclose a method and a system configured to exchange energy wirelessly, comprising a structure configured to exchange the energy wirelessly via a coupling of evanescent waves, wherein the structure is electromagnetic (EM) and non-radiative, and wherein the structure generates an EM near-field in response to receiving the energy; and a controller configured to tune up the structure such that the near-field is generated according a particular energy distribution pattern.
    Type: Grant
    Filed: December 29, 2009
    Date of Patent: April 9, 2013
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Koon Hoo Teo, Vishwanath Iyer, William S. Yerazunis, Chunjie Duan, Da Huang
  • Patent number: 8384247
    Abstract: A system exchanges energy wirelessly and includes a source configured to generate evanescent waves, in response to receiving the energy, on at least part of a surface of the source. The system also includes a sink configured to receive the energy wirelessly from the source via a coupling of the at least part of the evanescent waves and a load configured to receive the energy from the sink. The load and the sink are configured to move along the surface of the source such that the at least a part of the evanescent waves are coupled between the source and the sink within an energy transfer area.
    Type: Grant
    Filed: January 13, 2010
    Date of Patent: February 26, 2013
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: William S. Yerazunis, Vishwanath Iyer, Da Huang, Chunjie Duan, Koon Hoo Teo
  • Patent number: 8369379
    Abstract: Synchronization methods and systems for communications over a multi-band system are presented. A synchronization technique for communications over a multi-band system includes receiving a packet of preamble symbols respectively transmitted over a sequence of frequency sub-bands according to one of a plurality of frequency hopping patterns, wherein the plurality of frequency hopping patterns are partitioned into a plurality of disjoint groups, each group having a different associated periodicity; computing, in parallel, respective autocorrelation values of the packet received in a selected frequency sub-band at a plurality of symbol delays; and selecting one of the plurality of groups of frequency hopping patterns based on the autocorrelation values at the plurality of symbol delays.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: February 5, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Zhenzhen Ye, Chunjie Duan, Philip Orlik, Jinyun Zhang
  • Patent number: 8345808
    Abstract: An exemplary method is disclosed to accurately estimate the center frequency of a narrow-band interference (NBI). The exemplary method uses multi-stage autocorrelation-function (ACF) to estimate an NBI frequency. The exemplary method allows an accurate estimation of the center frequency of NBI in an Ultra-Wideband system. A narrow band interference (NBI) estimator based on such a method allows a low complexity hardware implementation. The exemplary method estimates the frequency in multiple stages. Each stage performs an ACF operation on the received signals. The first stage gives an initial estimation and the following stages refine the estimation. The results of all stages are combined to produce the final estimation. An apparatus based on such a multi-stage narrow band interference frequency detector is also disclosed to improve the accuracy by combining various filters with the detector.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: January 1, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Zhenzhen Ye, Chunjie Duan, Philip Orlik, Jinyun Zhang
  • Patent number: 8315205
    Abstract: A wireless network with a star topology has a first and second central node. The first central node starts up first and initiates the network. The second central node starts up second and synchronizes to the first central node, and wherein one node is in active mode and the other node is in standby mode, and a set of leaf nodes configured to communicate only with the active node.
    Type: Grant
    Filed: January 3, 2010
    Date of Patent: November 20, 2012
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Chunjie Duan, Jianlin Guo, Zhifeng Tao
  • Publication number: 20120217818
    Abstract: A system transfers energy wirelessly from a source to a sink as an EM near-field according to parameters. The source includes a receive RF chain, and a receive controller. The sink includes a transmit RF chain, and a receive controller. The receive controller measures the energy received as feedback information, which is transmitted to the sink. Then, the transmit controller dynamically varies the parameters to optimized the energy received at the sink.
    Type: Application
    Filed: August 12, 2011
    Publication date: August 30, 2012
    Inventors: William S. Yerazunis, Bingnan Wang, Chunjie Duan, John Barnwell, Dan J. Burns
  • Publication number: 20120217817
    Abstract: A system for exchanging energy wirelessly includes an array of objects, wherein each object is electromagnetic (EM) and non-radiative and generates an EM near-field in response to receiving the energy. Each object in the array is electrically isolated from the other objects and arranged at a distance from all other objects. An energy driver provides the energy to the array of objects. A receiver, at a relative position with respect to the array receives the energy via resonant coupling of evanescent waves. The system can tunes characteristics of the EM near-field depending on a relative position of the receiver with respect to the array. The tuning can affect frequency, phase and amplitude of the energy field.
    Type: Application
    Filed: August 12, 2011
    Publication date: August 30, 2012
    Inventors: Bingnan Wang, William S. Yerazunis, Chunjie Duan, Koon Hoo Teo
  • Publication number: 20120207027
    Abstract: Undetectable errors in packets are minimized by verifying the CRC in each packet, setting a CRC flag to 0 to indicate success, and setting the CRC flag to 1 to indicate failure. If at least one packet in the set of packets fails then generate an error pattern E for each packet by comparing the packet that fails with one packet that passed the CRC verification, and comparing the error pattern to a set of known error patterns. Then, setting a CRC flag to 0 to indicate success and passing the payload of each packet and the CRC flag to the application if the difference is less than a predetermined threshold, and otherwise, setting the CRC flag to 1 to indicate failure.
    Type: Application
    Filed: February 14, 2011
    Publication date: August 16, 2012
    Inventors: Chunjie Duan, Yige Wang
  • Patent number: 8238868
    Abstract: A dynamic voltage scaling system for a packet-based data communication transceiver includes a constant voltage supply, a variable voltage supply, and a voltage control unit. The constant voltage supply is configured to supply a constant voltage to at least one parameter-independent function of the transceiver, and the variable voltage supply is configured to supply a variable voltage in accordance with a control signal to at least one parameter-dependent function of the transceiver. Parameter-independent transceiver functions perform operations independent of a predetermined parameter and parameter-dependent transceiver functions perform operations dependent on the predetermined parameter The voltage control unit is configured to generate the control signal based on information provided by at least one parameter-independent transceiver function about the predetermined parameter.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: August 7, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Chunjie Duan, Sinan Gezici, Jinyun Zhang, Rajesh Garg
  • Publication number: 20120170684
    Abstract: A method estimates a wireless channel at a receiver. The signal is transmitted using narrowband orthogonal frequency division demultiplexing (OFDM) and frequency subcarriers, and the signal includes a set of data tones and a set of pilot tones. The channel and pilot tone interference are estimated based on all the pilot tones extracted from the signal and a channel model. The set of data are equalized based on the channel estimate. Data interference is detected according to the pilot interference and the equalized data tones. Subcarrier interference-to-noise ratios are determined based on the data interference. Signal strengths of the data tones are determined based on the equalized data tones, log-likelihood ratios of bits represented by the data tones are determined based on the subcarrier interference-to-noise ratios and the signal strength of the data tones.
    Type: Application
    Filed: December 30, 2010
    Publication date: July 5, 2012
    Inventors: Raymond Yim, Amitav Mukherjee, Philip V. Orlik, Chunjie Duan, Jinyun Zhang
  • Publication number: 20120148046
    Abstract: Data are communicated in a wireless network between a transmitter to a receiver. The transmitter estimates a first channel response between the receiver and the transmitter at the transmitter, and generating a first key based on the first channel response. The data are encoded at the transmitter using a rate-adaptive code to produce encoded data, which is scrambling using the first key before broadcasting. Subsequently, the receiver can estimate a second channel response to generate a second key to be used to descramble the broadcast data.
    Type: Application
    Filed: December 10, 2010
    Publication date: June 14, 2012
    Inventors: Chunjie Duan, Yige Wang, Wei Liu
  • Publication number: 20120147879
    Abstract: A hybrid communication network for a transportation safety system includes a fixed wired nodes and mobile wireless nodes. Because the wired nodes operate independently packets transmitted by the wired nodes to the wireless nodes need to be synchronized. A downlink travel time for downlink packets traveling from a controller to the wireless nodes is determined. Then, the controller schedules downlink data intervals (DDI) based on the downlink travel time; and transmits downlink packets to the wireless nodes during the DDI, such that a latency requirement of the transportation safety system is satisfied.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 14, 2012
    Inventors: Jianlin Guo, Raymond Yim, Jinyun Zhang, Philip V. Orlik, Chunjie Duan, Frederick J. Igo, JR.
  • Publication number: 20120147864
    Abstract: A hybrid communication network for a transportation safety system includes a wired network including a set of fixed nodes. Each fixed node includes a wired interface for connecting the fixed node to the wired network and at least one wireless interface. The set of fixed nodes further includes a head node at a first end of the wired network connected to a controller, a terminal node at a second end of the wired network, and a set of relay nodes arranged between the head node and the terminal node. A wireless network includes a set of mobile nodes and a set of fixed nodes connected to the wired network. Each mobile node includes at least one of the wireless interfaces, and each mobile node is arranged in a moveable car.
    Type: Application
    Filed: December 9, 2010
    Publication date: June 14, 2012
    Inventors: Jianlin Guo, Raymond Yim, Philip V. Orlik, Frederick J. Igo, JR., Chunjie Duan, Jinyun Zhang
  • Publication number: 20120140922
    Abstract: The first and second nodes in a wireless network estimate first and second channel response. The first node quantizes the first channel response to produce a first bit sequence, and a feed-forward message, which is transmit as a feed-forward message to the second node. The second node quantizes the second channel response using the feed-forward message to produce and an estimate of the first bit sequence, a second bit sequence and a feed-back message, which is transmitted to the first node. Then, the first and second nodes delete bits in the respective bit sequences using the feed-back and feed-forward message to generate first and second private keys with low bit mismatch rate.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 7, 2012
    Inventors: Ramesh Annavajjala, Wei Liu, Chunjie Duan, Toshiaki Koike-Akino, Yige Wang
  • Publication number: 20120129458
    Abstract: In a network for a safety system in a transportation system, the transportation system includes a shaft and a car arranged in the shaft. A first wall node is at a first end of the shaft and a second wall node is at a second end of the shaft to communicate safety messages with the car. Each wall node includes at least one wireless transceiver connected to one or more antennas. Each car in the shaft includes at least two wireless transceiver connected to one or more antennas, wherein the first transceiver of the car uses a first frequency and the second transceiver of the car uses a second frequency to communicate each safety messages in duplicate. A wired backbone connects the set of wall nodes to a controller of the safety system of the transportation system.
    Type: Application
    Filed: November 19, 2010
    Publication date: May 24, 2012
    Inventors: Raymond Yim, Philip V. Orlik, Chunjie Duan, Jinyun Zhang, Jianlin Guo, Frederick J. Igo, JR.
  • Patent number: 8179251
    Abstract: A wireless sensor network includes an initial set of anchors at known locations, and a set of sensors at unknown locations. Ranges, from each sensor to at least three of the anchors, determine a position, an anchor ranging weight, and an anchor position weight. For each anchor, the anchor ranging weight and the anchor position weight form a combined weight. A weighted least square (WLS) function for the positions and the combined weights is minimized to determine a position of the sensor, and a sensor position weight. The sensor is identified as being a member of a set of candidate anchor nodes, and the candidate anchor node with a largest sensor position weight is selected to be transformed to another anchor to minimize propagation of errors in the positions of the set of sensors.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: May 15, 2012
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Nayef Alsindi, Chunjie Duan, Jinyun Zhang
  • Patent number: 8155166
    Abstract: Embodiments of the invention disclose a system and a method for reducing inter-carrier interference (ICI) in a network, wherein the network uses orthogonal frequency division multiplexing (OFDM). The method generates, in a transmitter, a diversified signal, wherein a diversified signal includes diversified elements representing data elements, such that each data element is represented by a number of diversified elements, wherein the number equals a degree of diversity. The diversified signal is modified based on an orthogonal matrix producing a spread signal, wherein columns of the orthogonal matrix are formed by vectors, wherein the vectors are orthogonal or quasi-orthogonal to each others, and the spread signal is transmitted in the network.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: April 10, 2012
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Chunjie Duan, Weihua Gao
  • Patent number: 8126405
    Abstract: A method measures a time from transmitting a ranging signal to receiving the ranging signal via a channel of a wireless network, and a received signal strength (RSS) of the ranging signal. A distance is estimated based on the time, and a path loss based on the RSS. Probabilities of conditions of the channel are estimated based on the distance and the path loss, wherein the condition is in one of line-of-sight (LOS), or non-LOS (NLOS).
    Type: Grant
    Filed: February 10, 2009
    Date of Patent: February 28, 2012
    Assignee: Mitsubishi Electric Research Laboratory, Inc.
    Inventors: Chunjie Duan, Nayef Alsindi, Jinyun Zhang