Using Doppler Frequency Shift Patents (Class 342/357.78)
  • Patent number: 9888426
    Abstract: Various aspects of the disclosure relate to handoff of a user terminal in communication with a satellite network portal through a satellite. In some aspects, a satellite network portal and a user terminal use a satellite handoff information to determine when to handoff the user terminal from one cell to another and/or from one satellite to another. In some aspects, a user terminal sends capability information, location information, or other information to a satellite network portal whereby, based on this information, the satellite network portal generates the satellite handoff information and/or selects a handoff procedure for the user terminal. In some aspects, handoff of a user terminal to a different satellite involves the user terminal conducting satellite signal measurements and sending a measurement message to the satellite network portal. In some aspects, the satellite network portal generates new satellite handoff information as a result of receiving a measurement message.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: February 6, 2018
    Assignee: QUALCOMM Incorporated
    Inventors: Fatih Ulupinar, Punyaslok Purkayastha, Peter A Barany, Gene Wesley Marsh
  • Patent number: 9007262
    Abstract: The described invention allows for rapid geolocation of one or more RF emitters using a single moving collection platform. Inaccuracies of conventional frequency of arrival (FOA) geolocation methods are overcome by solving simultaneously for emitter location and a potential emitter drift associated with an observed emitter frequency. Certain embodiments may utilize particle filtering algorithms to recursively update multimodal state densities that are typical of solutions involving both unknown emitter location and nonstationary emitter carrier drift. Moreover, certain properties of particle filters may be exploited to provide a geolocation solution given a complex multimodal state space composed of emitter location and a non-stationary emitter frequency required for FOA.
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: April 14, 2015
    Assignee: Leidos, Inc.
    Inventor: Hanna E. Witzgall
  • Publication number: 20140354477
    Abstract: Technology to determine a satellite's orbit is disclosed. In an example, an orbital determination (OD) device for a satellite operable to determine a satellite's orbit can include computer circuitry configured to: Receive a single global positioning system-generated (GPS-generated) signal from a GPS satellite; decode an ephemeris of the GPS satellite from the GPS-generated signal; determine a Doppler shift and a Doppler trend of the GPS-generated signal; and generate a Doppler-GPS OD using the ephemeris of the GPS satellite and the Doppler shift and the Doppler trend of the GPS-generated signal fit to Kepler orbital elements of an orbit model.
    Type: Application
    Filed: May 29, 2013
    Publication date: December 4, 2014
    Inventor: Ian S. Robinson
  • Patent number: 8886225
    Abstract: Methods and apparatuses for determining a position of a mobile satellite positioning system (SPS) receiver which is coupled to a communication receiver or transceiver. In one exemplary method, a change in a communication signal received by the communication receiver is determined. A parameter, based on the change, is determined, and SPS signals from SPS satellites are processed according to the parameter. According to further details of this method, the change involves the fluctuation of the level of the communication signal and the parameter is a motion information which specifies a frequency range for searching for SPS signals in the process of acquiring the SPS signals from SPS satellites. In an alternative embodiment the change in the communication signal is a change in the transmitted signal in response to power control commands. Apparatuses, such as a mobile communication system which includes an SPS receiver and a communication receiver, are also described.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: November 11, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Norman F. Krasner
  • Publication number: 20140168011
    Abstract: A communication apparatus includes a Doppler shift amount calculation unit configured to calculate a Doppler shift amount of a reception signal which is obtained by modulating a signal, for which spectrum spreading is performed by using a predetermined spread code, by a predetermined carrier frequency, a frequency shift amount setting unit configured to set a frequency shift amount on the basis of the Doppler shift amount, a frequency conversion unit configured to shift the frequency of the reception signal by the frequency shift amount, a coherent addition unit configured to perform coherent addition of the reception signal, a spread code generation unit configured to generate a spread code, and a phase detection unit configured to perform correlation calculation between a calculation result of the coherent addition and the spread code and detect a phase of the spread code of the reception signal on the basis of the correlation calculation result.
    Type: Application
    Filed: November 6, 2013
    Publication date: June 19, 2014
    Applicant: Sony Corporation
    Inventor: Suguru Houchi
  • Patent number: 8615032
    Abstract: Sub-microsecond time transfer in a GPS/GNSS receiver using a weak GPS/GNSS signal is provided. The digitized complex baseband signal and the generated PN code are cross-correlated for each code period so as to output a complex correlation value at each code epoch of the generated PN code, where a sequence of the output correlation values form a data stream representing the navigation message. Bit synchronization generates bit sync pulses at bit boundaries. The location of a target segment having a known sequence at a known bit location in the navigation message is detected by searching through a plurality of subframes and accumulating search results for the plurality of subframes. Transmission time of the target segment is determined from the detected location of the target segment, with a certain time ambiguity. Accurate local time is determined by solving the time ambiguity using approximate time obtained from an external source.
    Type: Grant
    Filed: January 22, 2013
    Date of Patent: December 24, 2013
    Assignee: Magellan Systems Japan, Inc.
    Inventor: Lawrence R. Weill
  • Patent number: 8599067
    Abstract: A global positioning satellite (GPS) receiver that includes a radio frequency (RF) receiver receiving a first GPS signal from a GPS satellite and a processor. The processor is configured to correlate the first GPS signal with a plurality of reference signals to produce a plurality of correlations, detect a transition between receiving the first GPS signal and receiving a second GPS signal from the GPS satellite based on a phase shift in the correlations, and if the transition is detected, compensate for the phase shift when computing a range to the GPS satellite.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: December 3, 2013
    Assignee: Cambridge Silicon Radio Ltd.
    Inventor: Gary Lennen
  • Patent number: 8521179
    Abstract: A mobile unit's position measurement apparatus is provided. The apparatus includes an observation data selection portion that calculates a plurality of estimated error values that correspond respectively to the plurality of pieces of observation data obtained by observing the signals received by the reception portion, that generates groups each of which includes estimated error values corresponding to at least a predetermined number of satellites, and then extracts, from the estimated error value groups generated, in which a difference between a maximum value and a minimum value of the estimated error values included is less than a predetermined value, and that consequently selects pieces of observation data provided by the signals from the satellites that correspond to the estimated error values that are included in an estimated error value group whose standard deviation of the estimated error values is smallest among the estimated error value groups extracted.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: August 27, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Naoto Hasegawa
  • Patent number: 8462044
    Abstract: The present invention provides a method and apparatus for determining the transmit location of an emitter using a single geostationary satellite. In an embodiment, a signal is received at a ground station from the emitter and relayed by the geostationary satellite. The signal is received at the ground station at a plurality of time instances and has a plurality of observed frequencies, one for each time instance. A plurality of lines of position are determining based on the plurality of observed frequencies. The transmit location of the emitter is determined based on at least one intersection among the plurality of lines of position.
    Type: Grant
    Filed: January 26, 2011
    Date of Patent: June 11, 2013
    Assignee: Glowlink Communications Technology, Inc.
    Inventors: Dominic K. C. Ho, Jeffrey C. Chu, Michael L. Downey
  • Patent number: 8421670
    Abstract: The present invention provides a position estimation apparatus, mounted at mobile object, including: an acquisition section that acquires transmission source information transmitted from each plural information transmission sources including, information relating to a position of information transmission source, information relating to a distance between information transmission source and mobile object, and information relating to a relative velocity of mobile object with respect to information transmission sources; a trajectory calculation section that calculates, over predetermined duration, a trajectory of mobile object by integrating velocity vectors of mobile object obtained based on transmission source information; and an estimation section that estimates, as a position of mobile object, a position for which trajectory is translated such that a difference between, distances between a plurality of points at different times on trajectory and respective information transmission sources, and acquired dista
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: April 16, 2013
    Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho
    Inventors: Yoshiko Kojima, Junichi Meguro, Noriyoshi Suzuki
  • Patent number: 8391341
    Abstract: Sub-microsecond time transfer in a GPS/GNSS receiver using a weak GPS/GNSS signal is provided. The digitized complex baseband signal and the generated PN code are cross-correlated for each code period so as to output a complex correlation value at each code epoch of the generated PN code, where a sequence of the output correlation values form a data stream representing the navigation message. Bit synchronization generates bit sync pulses at bit boundaries. The location of a target segment having a known sequence at a known bit location in the navigation message is detected by searching through a plurality of sub-frames and accumulating search results for the plurality of subframes. Transmission time of the target segment is determined from the detected location of the target segment, with a certain time ambiguity. Accurate local time is determined by solving the time ambiguity using approximate time obtained from an external source.
    Type: Grant
    Filed: December 12, 2008
    Date of Patent: March 5, 2013
    Assignee: Magellan Systems Japan, Inc.
    Inventor: Lawrence R. Weill
  • Patent number: 8391340
    Abstract: A low-cost GPS/GNSS receiver receives a satellite signal at an RF frequency (fRF). The GPS/GNSS receiver includes a front end section for receiving the satellite signal and generating a digital complex signal having a first bandwidth, the received satellite signal being converted into a complex signal before digitizing, a signal capturing section for searching for and acquiring the satellite signal, the signal capturing section including a capture memory, a baseband processor for tracking the acquired satellite signal, and a signal splitter coupled to the front end section. The signal splitter splits the digital complex signal into two bandwidths, by generating a narrowband digital complex signal having a second bandwidth substantially smaller than the first bandwidth. The signal splitter provides the narrowband digital signal to the capture memory and the wider first bandwidth digital complex signal to the baseband processor.
    Type: Grant
    Filed: September 15, 2008
    Date of Patent: March 5, 2013
    Assignee: Magellan Systems Japan, Inc.
    Inventor: Lawrence R. Weill
  • Patent number: 8379782
    Abstract: The described method characterizes scattering objects in a wireless channel. The present invention determines non-equally spaced path delays and Doppler parameters for a plurality of scattering objects in a wireless channel. More particularly, a frequency-to-time transform applied to a plurality of OFDM pilot samples received over a plurality of OFDM symbol periods generates a set of non-equally spaced path delays and a set of associated complex delay coefficients. Further, a time-to-frequency transform applied to the complex delay coefficients determined for one path delay over multiple OFDM symbol periods generates a set of Doppler parameters comprising a plurality of non-equally spaced Doppler frequencies and their corresponding scattering coefficients for that path delay.
    Type: Grant
    Filed: June 4, 2009
    Date of Patent: February 19, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Paul Wilkinson Dent, Leonid Krasny
  • Patent number: 8378887
    Abstract: There are situations where GPS signals are received from less than four satellites. In order to improve the GPS location availability, disclosed here are systems and methods for synthesizing GPS measurements, which, together with fewer than four available real GPS signals, can be used to calculate a position fix. In particular, GPS range measurements for lost satellites, which are satellites that were previously tracked but are now not tracked, are synthesized to improve GPS signal availability. The synthesized measurements are used along with real measurements to enable accurate position fix even when GPS satellite availability is poor. Different synthesized measurement generation schemes, depending on whether an INS/DR aiding system is available, are further described herein.
    Type: Grant
    Filed: April 4, 2012
    Date of Patent: February 19, 2013
    Assignee: CSR Technology Inc.
    Inventors: Gang Xie, Makarand Shankar Phatak, Mangesh Chansarkar, Anil Kumar Kandangath
  • Patent number: 8369873
    Abstract: Methods and apparatuses for determining a position of a mobile satellite positioning system (SPS) receiver which is coupled to a communication receiver or transceiver. In one exemplary method, a change in a communication signal received by the communication receiver is determined. A parameter, based on the change, is determined, and SPS signals from SPS satellites are processed according to the parameter. According to further details of this method, the change involves the fluctuation of the level of the communication signal and the parameter is a motion information which specifies a frequency range for searching for SPS signals in the process of acquiring the SPS signals from SPS satellites. In an alternative embodiment the change in the communication signal is a change in the transmitted signal in response to power control commands. Apparatuses, such as a mobile communication system which includes an SPS receiver and a communication receiver, are also described.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: February 5, 2013
    Assignee: QUALCOMM Incorporated
    Inventor: Norman F. Krasner
  • Patent number: 8355473
    Abstract: Certain embodiments of the present disclosure propose methods and systems for classifying the Doppler spread based on the output of the frequency-tracking loop (FTL) discriminator in WiMAX systems to improve the performance of the channel estimation. The Doppler spread may be classified as low, medium or high based on the statistics of the output of the discriminator in the fine-tracking mode.
    Type: Grant
    Filed: April 19, 2009
    Date of Patent: January 15, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Junqiang Li, Je Woo Kim, Madihally J. Narasimha
  • Patent number: 8305269
    Abstract: A radio signal-based positioning device includes a receiver that receives a plurality of radio-transmitted positioning signals, a frequency determiner that determines a frequency of each of the plurality of positioning signals, a send time determiner that determines a send time of each of the plurality of positioning signals, and an evaluation unit that determines a position location from the determined frequencies and send times of the plurality of positioning signals.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: November 6, 2012
    Assignee: Astrium GmbH
    Inventors: Jan M. W. Krueger, Hans L. Trautenberg
  • Patent number: 8238490
    Abstract: A method for determining a Doppler shift of a first signal is provided. First, a plurality of Doppler frequency hypotheses is combined to obtain a joint Doppler signal. The first signal is the correlated according to the joint Doppler signal and a plurality of code signals with phases corresponding to a series of code phase hypotheses to obtain a series of correlation results which are then examined to determine whether the Doppler shift does lie in the Doppler hypotheses. A fine Doppler search is then performed to determine the Doppler shift when the Doppler shift lies in the Doppler hypotheses.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: August 7, 2012
    Assignee: Mediatek Inc.
    Inventors: Hsin-Chung Yeh, Kuan-I Li
  • Patent number: 8212720
    Abstract: Embodiments of the invention provide a method of detecting movement to aid GNSS receivers. By detecting when the user is stationary, the Doppler frequency estimation can be corrected or the SNR can be boosted more both of which lead to improved performance. The embodiments allow a GNSS receiver to process signals in when the signal level would otherwise be too low—for example indoors. The embodiments can improve performance when one or more satellites are temporarily blocked but one or more satellites are still being tracked.
    Type: Grant
    Filed: September 24, 2009
    Date of Patent: July 3, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Deric W. Waters, June Chul Roh, Sandeep Rao
  • Patent number: 8159393
    Abstract: There are situations where GPS signals are received from less than four satellites. In order to improve the GPS location availability, disclosed here are systems and methods for synthesizing GPS measurements, which, together with fewer than four available real GPS signals, can be used to calculate a position fix. In particular, GPS range measurements for lost satellites, which are satellites that were previously tracked but are now not tracked, are synthesized to improve GPS signal availability. The synthesized measurements are used along with real measurements to enable accurate position fix even when GPS satellite availability is poor. Different synthesized measurement generation schemes, depending on whether an INS/DR aiding system is available, are further described herein.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: April 17, 2012
    Assignee: CSR Technology Inc.
    Inventors: Gang Xie, Makarand Shankar Phatak, Mangesh Chansarkar, Anil Kumar Kandangath
  • Patent number: 8125378
    Abstract: This disclosure is directed to systems and methods for providing GPS positioning determinations from a single set of Doppler measurements from a plurality of satellites in conjunction with satellite ephemeris data and a rough GPS time estimate. Measured Doppler velocities are compared with Doppler velocities calculated from ephemeris data and used to estimate the receiver position.
    Type: Grant
    Filed: June 2, 2009
    Date of Patent: February 28, 2012
    Assignee: Qualcomm Atheros, Inc.
    Inventor: Janne Jarpenvaa
  • Patent number: 8121621
    Abstract: A position of a mobile communication terminal in an environment where the terminal cannot communicate with a GPS is defined more narrowly than a sector area of a base station in which the mobile communication terminal is located so that the position of the mobile communication terminal can be estimated more accurately. Even if a mobile communication terminal is in an environment where the terminal cannot communicate with a GPS, the latitude and longitude of the center of a sector of the wireless base station in which the mobile communication terminal is located is obtained according to a predetermined calculation by a base station database device, and the obtained latitude and longitude is sent back as an estimated latitude and longitude of the mobile communication terminal to the mobile communication terminal via the wireless base station.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: February 21, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Jin Hoshino, Susumu Ogata, Masatoshi Kimoto
  • Patent number: 8094070
    Abstract: A fast position tracking method and apparatus, the fast position tracking method including the operations of receiving a satellite signal from a plurality of satellites; demodulating satellite data received from a predetermined satellite from among the plurality of satellites by using a pseudo random noise code and a carrier which correspond to the satellite signal; estimating information about satellite data which is at a current time and which is from among the demodulated satellite data according to a real-time clock (RTC) counter; and determining a position.
    Type: Grant
    Filed: July 15, 2009
    Date of Patent: January 10, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seung-hyun Yoon, Su-bong Kim
  • Patent number: 8050691
    Abstract: The present invention relates to a method and an arrangement in a mobile telecommunication network for detection of a UE transmitted signal. The arrangement comprises means for detecting the signal during the time ttot, wherein said means comprises a correlator adapted for combined coherent and non-coherent correlation, wherein the length of the coherent correlation interval is L signal samples, the number of coherent correlation intervals is M and the coherent correlation results in a coherent correlation result for each of the coherent detection intervals M, and means for adding the coherent correlation results non-coherently. Further, the arrangement comprises means for selecting one of the length L of coherent detection interval and the total detection interval ttot based on at least one of the parameters cell size, UE speed and acceleration, number of participating Location Measurements Units and a desired total false alarm rate.
    Type: Grant
    Filed: August 2, 2006
    Date of Patent: November 1, 2011
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Ari Kangas
  • Patent number: 8040275
    Abstract: Aspects of the disclosure provide methods for positioning transmitting stations, such as cell towers. Further, aspects of the disclosure provide a database for storing information of the transmitting stations. In addition, aspects of the disclosure provide methods for positioning a moving object having a receiver based on the database of the transmitting stations and wireless signals transmitted by the transmitting stations. The methods increase in-transit location visibility of shipment while reducing GNSS usage, and thus reduce power consumption. The methods allow positioning receiving stations when GNSS signals may not be available, such as due to interference.
    Type: Grant
    Filed: July 15, 2009
    Date of Patent: October 18, 2011
    Assignee: Lockheed Martin Corporation
    Inventors: Douglas S. Ronald, Tim D. Stevens, Paul A. Quintana, Jennifer Wang
  • Patent number: 8013786
    Abstract: Embodiments of the present invention recite a method and system for limiting the functionality of a mobile electronic device. In one embodiment, a Global Navigation Satellite System (GNSS) receiver configured to determine a GNSS Doppler frequency shift measurement corresponding to a GNSS signal. A control component is configured to control an operation of the mobile electronic device in response to a control signal which is generated when the GNSS Doppler frequency shift measurement is used to determine that the speed of the mobile electronic device exceeds a speed threshold.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: September 6, 2011
    Assignee: Trimble Navigation Limited
    Inventor: David Gildea
  • Publication number: 20110199260
    Abstract: A GNSS enabled mobile device concurrently receives GNSS signals from GNSS satellites and transmissions from a cellular base station. GNSS-based velocities and GNSS locations are determined for the GNSS enabled mobile device utilizing the received GNSS signals. A cellular Doppler is measured on the cellular base station. A location of the cellular base station is determined based on the determined GNSS-based velocity and corresponding cellular Doppler measurements. The cellular base station may be located by the GNSS enabled mobile device and/or by a remote location server. In this regard, the remote location server may determine the location for the cellular base station utilizing GNSS velocities and corresponding cellular Doppler measurements received from plural GNSS enabled mobile devices in a coverage area of the cellular base station. The determined location of the cellular base station is used to refine GNSS locations of the plurality of GNSS enabled mobile devices when needed.
    Type: Application
    Filed: March 26, 2010
    Publication date: August 18, 2011
    Inventors: David Garrett, Charles Abraham, Mark Buer, Jeyhan Karaoguz, David Albert Lundgren, David Murray, Frank van Diggelen
  • Patent number: 7995682
    Abstract: A method and apparatus for estimating a satellite signal parameter in a satellite positioning system receiver is described. In an example, a plurality of correlation results between a satellite signal and a reference signal is generated and stored in a memory. At least one satellite signal parameter is estimated from the plurality of correlation results using a co-processor integrated within the satellite positioning system receiver. As the coprocessor estimates the parameter, new correlation results are added to the memory. The at least one satellite signal parameter is then provided to the processor.
    Type: Grant
    Filed: December 19, 2005
    Date of Patent: August 9, 2011
    Assignee: Broadcom Corporation
    Inventors: Charles Abraham, Emre Tapucu
  • Patent number: 7991362
    Abstract: A wireless terminal determines the position of a moving base station and determines timing and/or frequency corrections. A wireless terminal determines its relative position with respect to the base station and determines a timing adjustment correction. The wireless terminal applies the determined timing correction to control uplink signaling timing and achieve synchronization at the base station's receiver. The wireless terminal determines its relative velocity with respect to the moving base station and determines a Doppler shift adjustment which it adds to the uplink carrier frequency or to its baseband signal. Base station position is determined from the current time and stored information correlating the base station position with time, e.g., for a geo-synchronous satellite. Base station position information, e.g., a GPS derived base station position fix, is determined from downlink airlink broadcast information, e.g., for an aircraft base station.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: August 2, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Frank A. Lane, Rajiv Laroia, Junyi Li
  • Patent number: 7812764
    Abstract: A terminal apparatus includes a control unit and a positioning device. The control unit determines a first satellite-to-be-acquired from among a plurality of SPS satellites, and generates an initial search frequency for the first satellite-to-be-acquired. The positioning device has a plurality of search units, and is configured to acquire the first satellite-to-be-acquired using the plurality of search units. The control unit determines first difference information, which is a difference between the initial search frequency and the frequency at which the first satellite-to-be-acquired is acquired. The control unit generates corrected search frequencies for other SPS satellites, using the first difference information. The positioning device acquires other necessary SPS satellites using the corresponding corrected search frequencies. The terminal apparatus can acquire SPS satellites accurately even when there has been a frequency shift in the terminal apparatus since the last positioning.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: October 12, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Shunichi Mizuochi, Akifumi Hayashi
  • Publication number: 20100253578
    Abstract: A navigation system comprises a radio receiver for the data acquisition of navigation satellite signals, a memory in which to store samples of those signals, and a post-processing unit to replay and signal-process the data in the memory to extract an original position fix for the radio receiver when it acquired the original navigation satellite signals.
    Type: Application
    Filed: November 24, 2008
    Publication date: October 7, 2010
    Inventor: Jose R. B. Mantovani
  • Patent number: 7800536
    Abstract: A Doppler frequency searching method and correlator are disclosed. In the present invention, before Doppler frequency removal, a received signal is converted into digital form and the spreading code is removed. Then the signal is down-sampled to have a low sampling rate, which can be determined according to the maximum Doppler frequency to be searched. The Doppler frequency searching is done by stages. Each stage is in charge of a portion of the Doppler frequency to be removed. The sampling rate can be further reduced in each stage. Each stage can have a plurality of Doppler frequency removal units sharing the portion of Doppler frequency that the stage is to remove. Power consumption is reduced since Doppler frequency removal is executed with low sampling rate.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: September 21, 2010
    Assignee: MEDIATEK, Inc.
    Inventor: Kun-tso Chen