Patents by Inventor Yuki Tokunaga

Yuki Tokunaga 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: 20240029487
    Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.
    Type: Application
    Filed: September 29, 2023
    Publication date: January 25, 2024
    Applicants: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Patent number: 11776334
    Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.
    Type: Grant
    Filed: February 8, 2021
    Date of Patent: October 3, 2023
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Yuki Tokunaga
  • Patent number: 11447099
    Abstract: A system includes antenna circuits void of transceivers, a multiplexer connected to the antenna circuits, a transceiver and a control module. The transceiver is connected to the multiplexer and cycles through the antenna circuits to facilitate determination of a location of a portable access device relative to a vehicle. The transceiver allocates periods of time for each of the antenna circuits and during each period of time exchanges radio frequency signals with the portable access device to obtain timing information associated with transmission of the radio frequency signals or a range estimate of the portable access device relative to the vehicle. The range estimates are estimates of distances between the antenna circuits and the portable access device. The location is determined based on the timing information or the range estimates. The control module, based on the determined location, provides access to the vehicle or control of a vehicle system.
    Type: Grant
    Filed: August 18, 2020
    Date of Patent: September 20, 2022
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Osman Ahmed, Jagadeesh Krishnamurthy, Yuki Tokunaga
  • Patent number: 11230260
    Abstract: A mobile access device includes a transceiver and a control module. The transceiver transmits and receives ultra-wideband signals including a first challenge signal. The control module: transmits via the transceiver the first challenge signal to a vehicle, where the first challenge signal is associated with a passive entry or a passive start operation of the vehicle, based on the first challenge signal, receive a response signal from the vehicle, determine a distance between the mobile access device and the vehicle based on the response signal, determine a wait period based on the distance, wait a minimum period, where the minimum period is a minimum of (i) the wait period and (ii) an advertisement period or a predetermined ranging period, and subsequent to waiting the minimum period, transmit a second challenge signal to the vehicle to update the distance between the mobile access device and the vehicle.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: January 25, 2022
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Osman Ahmed, Yuki Tokunaga
  • Publication number: 20210402955
    Abstract: A mobile access device includes a transceiver and a control module. The transceiver transmits and receives ultra-wideband signals including a first challenge signal. The control module: transmits via the transceiver the first challenge signal to a vehicle, where the first challenge signal is associated with a passive entry or a passive start operation of the vehicle, based on the first challenge signal, receive a response signal from the vehicle, determine a distance between the mobile access device and the vehicle based on the response signal, determine a wait period based on the distance, wait a minimum period, where the minimum period is a minimum of (i) the wait period and (ii) an advertisement period or a predetermined ranging period, and subsequent to waiting the minimum period, transmit a second challenge signal to the vehicle to update the distance between the mobile access device and the vehicle.
    Type: Application
    Filed: June 26, 2020
    Publication date: December 30, 2021
    Inventors: Osman AHMED, Yuki TOKUNAGA
  • Patent number: 11127234
    Abstract: A method of communicating with a portable access device includes iteratively performing an algorithm via an access module of a vehicle. The algorithm includes a series of operations including: selecting a frequency from multiple frequencies; selecting an antenna pair from multiple possible antenna pairs, where antennas of the possible antenna pairs include antennas with different polarized axes; transmitting a packet to the portable access device via the selected antenna pair; receiving a first RSSI and a response signal from the portable access device, the first RSSI corresponds to the transmission of the packet; and measuring a second RSSI of the response signal; based on the first RSSIs and the second RSSIs. A best one of the frequencies and a best antenna pair of the possible antenna pairs are selected. One or more additional packets are transmitted using the selected best frequency and the selected best antenna pair.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: September 21, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Warren Guthrie, Osman Ahmed, Yuki Tokunaga
  • Publication number: 20210166509
    Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.
    Type: Application
    Filed: February 8, 2021
    Publication date: June 3, 2021
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Patent number: 11010996
    Abstract: A system includes a transmitter, a receiver and a control module. The transmitter transmits a RF signal from one of a vehicle and a portable access device to the other one of the vehicle and the portable access device. The receiver receives a response signal from one of the vehicle and the portable access device in response to the RF signal. The control module: converts the response signal to in-phase and quadrature-phase signals; based on the RF, in-phase signal and quadrature-phase signals; detects a range extension type relay attack performed by an attacking device to obtain at least one of access to or operational control of the vehicle; where the RF signal is relayed via the attacking device from the vehicle to the portable access device or the response signal is relayed via the attacking device from the portable access device to the vehicle; and performs a countermeasure.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: May 18, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, John Videtich, Yuki Tokunaga
  • Patent number: 10984615
    Abstract: A system for accessing or providing operational control of a vehicle includes initiator and sniffer devices. The initiator device includes: polarized antennas; a transmitter transmitting a first tone signal via the polarized antennas from the vehicle to a responder/portable access device; and receiver receiving a second tone signal from the responder device in response to the first tone signal. The sniffer device includes: second polarized antennas; and a second receiver receiving, via the second polarized antennas, the first tone signal from the transmitter and the second tone signal from the responder device. The sniffer device determines states of the first and second tone signals including respective phase delays. The initiator or sniffer device estimates a first distance from the vehicle to the responder device or a second distance from the responder device to the sniffer device based on the states including respective phase delays.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: April 20, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Yuki Tokunaga
  • Patent number: 10943417
    Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: March 9, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Yuki Tokunaga
  • Publication number: 20210061225
    Abstract: A system includes antenna circuits void of transceivers, a multiplexer connected to the antenna circuits, a transceiver and a control module. The transceiver is connected to the multiplexer and cycles through the antenna circuits to facilitate determination of a location of a portable access device relative to a vehicle. The transceiver allocates periods of time for each of the antenna circuits and during each period of time exchanges radio frequency signals with the portable access device to obtain timing information associated with transmission of the radio frequency signals or a range estimate of the portable access device relative to the vehicle. The range estimates are estimates of distances between the antenna circuits and the portable access device. The location is determined based on the timing information or the range estimates. The control module, based on the determined location, provides access to the vehicle or control of a vehicle system.
    Type: Application
    Filed: August 18, 2020
    Publication date: March 4, 2021
    Inventors: Osman AHMED, Jagadeesh KRISHNAMURTHY, Yuki TOKUNAGA
  • Patent number: 10902691
    Abstract: A system for accessing or providing operational control of a vehicle includes a network device and a control module. The network device includes: an antenna module including antennas with different polarized axes; a transmitter transmitting a series of tones via the antenna module from the vehicle to a second network device and change the frequencies of the tones during the transmission of the series of tones, where, at any moment in time, at least one of the antennas is not cross-polarized with an antenna of the second network device; and a receiver receiving the series of tones from the second network device. The control module: determines differences in phases of the series of tones versus differences in frequencies of the series of tones; and based on the differences in the phases and the differences in the frequencies, determines a distance between the first network device and the second network device.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: January 26, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Yuki Tokunaga
  • Patent number: 10885729
    Abstract: A system for providing operational control of a vehicle includes a first network device and control module. The first network device includes: polarized antennas; a transmitter transmitting an initiator packet via the polarized antennas from the vehicle to a second network device including a synchronization access word and a CW tone, one of the first and second network devices is implemented within the vehicle, the other one of the first and second network devices is a portable access device, and at any moment in time, at least one of the polarized antennas is not cross-polarized with an antenna of the second network device; and a receiver receiving a response packet from the second network device including the synchronization access word and the first CW tone. A control module determines a difference in RTT between the initiator and response packets and detects a range extension type relay attack.
    Type: Grant
    Filed: October 10, 2019
    Date of Patent: January 5, 2021
    Assignees: DENSO International America, Inc., DENSO CORPORATION
    Inventors: Raymond Michael Stitt, Yuki Tokunaga
  • Publication number: 20200120509
    Abstract: A system includes a transmitter, a receiver and a control module. The transmitter transmits a RF signal from one of a vehicle and a portable access device to the other one of the vehicle and the portable access device. The receiver receives a response signal from one of the vehicle and the portable access device in response to the RF signal. The control module: converts the response signal to in-phase and quadrature-phase signals; based on the RF, in-phase signal and quadrature-phase signals; detects a range extension type relay attack performed by an attacking device to obtain at least one of access to or operational control of the vehicle; where the RF signal is relayed via the attacking device from the vehicle to the portable access device or the response signal is relayed via the attacking device from the portable access device to the vehicle; and performs a countermeasure.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, John VIDETICH, Yuki TOKUNAGA
  • Publication number: 20200114875
    Abstract: A system for includes master and sniffer devices. The master device includes: first antennas with different polarized axes; a transmitter transmitting a challenge signal via the first antennas from the vehicle to a slave device, where the slave device is a portable access device; and a receiver receiving a response signal in response to the challenge signal from the slave device. The sniffer device includes: second antennas with different polarized axes; and a receiver receiving, via the second antennas, the challenge signal from the transmitter and the response signal from the slave device. The sniffer device measures when the challenge signal and the response signal arrive at the sniffer device to provide arrival times. The master or sniffer device estimates at least one of a distance from the vehicle to the slave device or a location of the slave device relative to the vehicle based on the arrival times.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Publication number: 20200118374
    Abstract: A system for providing operational control of a vehicle includes a first network device and control module. The first network device includes: polarized antennas; a transmitter transmitting an initiator packet via the polarized antennas from the vehicle to a second network device including a synchronization access word and a CW tone, one of the first and second network devices is implemented within the vehicle, the other one of the first and second network devices is a portable access device, and at any moment in time, at least one of the polarized antennas is not cross-polarized with an antenna of the second network device; and a receiver receiving a response packet from the second network device including the synchronization access word and the first CW tone. A control module determines a difference in RTT between the initiator and response packets and detects a range extension type relay attack.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Publication number: 20200119464
    Abstract: A system for accessing or providing operational control of a vehicle includes initiator and sniffer devices. The initiator device includes: polarized antennas; a transmitter transmitting a first tone signal via the polarized antennas from the vehicle to a responder/portable access device; and receiver receiving a second tone signal from the responder device in response to the first tone signal. The sniffer device includes: second polarized antennas; and a second receiver receiving, via the second polarized antennas, the first tone signal from the transmitter and the second tone signal from the responder device. The sniffer device determines states of the first and second tone signals including respective phase delays. The initiator or sniffer device estimates a first distance from the vehicle to the responder device or a second distance from the responder device to the sniffer device based on the states including respective phase delays.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Publication number: 20200118372
    Abstract: A method of communicating with a portable access device includes iteratively performing an algorithm via an access module of a vehicle. The algorithm includes a series of operations including: selecting a frequency from multiple frequencies; selecting an antenna pair from multiple possible antenna pairs, where antennas of the possible antenna pairs include antennas with different polarized axes; transmitting a packet to the portable access device via the selected antenna pair; receiving a first RSSI and a response signal from the portable access device, the first RSSI corresponds to the transmission of the packet; and measuring a second RSSI of the response signal; based on the first RSSIs and the second RSSIs. A best one of the frequencies and a best antenna pair of the possible antenna pairs are selected. One or more additional packets are transmitted using the selected best frequency and the selected best antenna pair.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, Warren GUTHRIE, Osman AHMED, Yuki TOKUNAGA
  • Publication number: 20200119463
    Abstract: A system for accessing or providing operational control of a vehicle includes a network device and a control module. The network device includes: an antenna module including antennas with different polarized axes; a transmitter transmitting a series of tones via the antenna module from the vehicle to a second network device and change the frequencies of the tones during the transmission of the series of tones, where, at any moment in time, at least one of the antennas is not cross-polarized with an antenna of the second network device; and a receiver receiving the series of tones from the second network device. The control module: determines differences in phases of the series of tones versus differences in frequencies of the series of tones; and based on the differences in the phases and the differences in the frequencies, determines a distance between the first network device and the second network device.
    Type: Application
    Filed: October 10, 2019
    Publication date: April 16, 2020
    Inventors: Raymond Michael STITT, Yuki TOKUNAGA
  • Patent number: 10604112
    Abstract: A control system includes: a transmission device that transmits a plurality of signals having different frequencies from one of a first communication unit mounted in a vehicle and a second communication unit mounted in a mobile device carried by a user in such a manner that the plurality of signals are combined to generate a predetermined composite signal in an area located at a distance from the first communication unit, the distance being not more than a predetermined distance; and a permission device that permits a predetermined action of the vehicle when the predetermined composite signal generated in the area from the plurality of signals transmitted by the transmission device is detected and an authentication signal transmitted by the second communication unit is authenticated as an authorized authentication signal for the vehicle.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: March 31, 2020
    Assignees: DENSO CORPORATION, SOKEN, INC.
    Inventors: Munenori Matsumoto, Yuki Tokunaga