Patents by Inventor Huaiyi Wang

Huaiyi Wang 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: 11714154
    Abstract: Techniques for determining a location of a client device using recursive phase vector subspace estimation are described. One technique includes receiving a plurality of angle-of-arrival (AoA) measurements from a plurality of access points (APs). Each AoA measurement includes a plurality of entries for phase values measured from a signal received from a client device at the plurality of APs. At least one AoA measurement of the plurality of AoA measurements that includes at least one of: (i) one or more entries with missing phase values and (ii) one or more entries with erroneous phase values is identified, based on a recursive phase estimation. The plurality of AoA measurements are updated based on the identified at least one AoA measurement. The location of the client device is determined, based on the updated plurality of AoA measurements.
    Type: Grant
    Filed: May 5, 2020
    Date of Patent: August 1, 2023
    Assignee: Cisco Technology, Inc.
    Inventors: Zhigang Gao, Matthew A. Silverman, Fred J. Anderson, Huaiyi Wang
  • Patent number: 11460534
    Abstract: Embodiments herein describe performing AoA resolving to identify a plurality of AoAs corresponding to a multipath signal and then using AP voting to identify a location of the client device. AoA resolving enables an AP to identify the different angles at which a multipath signal reaches the AP. That is, due to reflections, a wireless signal transmitted by a single client device may reach the AP using multiple paths that each has their own AoA. The AP can perform AoA resolving to identify the AoAs for the different paths in a multipath signal. In one embodiment, the AoAs for two APs (or a subset of the APs) can be used to identify cross points or intersection points that represent candidate locations of the client device. A voting module can determine whether those cross points corresponds to AoAs identified by the remaining APs.
    Type: Grant
    Filed: January 21, 2020
    Date of Patent: October 4, 2022
    Assignee: Cisco Technology, Inc.
    Inventors: Zhigang Gao, Matthew A. Silverman, Paul J. Stager, Huaiyi Wang
  • Patent number: 11374704
    Abstract: Aspects described herein include a method comprising predicting, based on one or more transmission characteristics, error values for a sequence of bit positions used for modulating data within a packet. The method further comprises generating a bitmap that maps one or more payload bits and one or more padding bits of the packet to respective bit positions of the sequence. The one or more padding bits are preferentially mapped to respective bit positions having relatively greater error values. The method further comprises modulating the sequence according to the bitmap.
    Type: Grant
    Filed: May 7, 2020
    Date of Patent: June 28, 2022
    Assignee: Cisco Technology, Inc.
    Inventors: Huaiyi Wang, Brian D. Hart, Matthew A. Silverman, Zhigang Gao
  • Patent number: 11368236
    Abstract: A wireless node in a wireless communication network. The wireless node includes one or more interfaces configured to receive wireless transmissions, a memory comprising instructions, and a hardware processor. The wireless node samples a received wireless transmission into a plurality of time-based subdivisions for each subdivision of the wireless transmission the wireless node determines a cross-correlation between the subdivision and a local syncword. The local syncword is constructed to correlate to any primary synchronization signal, PSS, of a plurality of PSSs defined for synchronization in the wireless network. The wireless node, based on the cross-correlation, determines whether one PSS of the plurality of PSSs is present in the subdivision of the wireless transmission.
    Type: Grant
    Filed: September 6, 2019
    Date of Patent: June 21, 2022
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Huaiyi Wang, Matthew Aaron Silverman, Zhigang Gao, Evgeny Yankevich
  • Publication number: 20210392497
    Abstract: Aspects described herein provide for hardening an RF signature by dynamically utilizing a sending device carrier frequency offset (CFO) as part of the RF signature. The CFO and the CFO varying pattern of wireless devices observed. A radio frequency signature at a sending device is paired to a frequency offset estimation algorithm at a receiving device, the final CFO estimation error may be bounded to a small range for various applications and communication protocols, and utilized to properly identify the sending device at the receiving device.
    Type: Application
    Filed: June 15, 2020
    Publication date: December 16, 2021
    Inventors: Zhigang GAO, Huaiyi WANG
  • Publication number: 20210349171
    Abstract: Techniques for determining a location of a client device using recursive phase vector subspace estimation are described. One technique includes receiving a plurality of angle-of-arrival (AoA) measurements from a plurality of access points (APs). Each AoA measurement includes a plurality of entries for phase values measured from a signal received from a client device at the plurality of APs. At least one AoA measurement of the plurality of AoA measurements that includes at least one of: (i) one or more entries with missing phase values and (ii) one or more entries with erroneous phase values is identified, based on a recursive phase estimation. The plurality of AoA measurements are updated based on the identified at least one AoA measurement. The location of the client device is determined, based on the updated plurality of AoA measurements.
    Type: Application
    Filed: May 5, 2020
    Publication date: November 11, 2021
    Inventors: Zhigang GAO, Matthew A. SILVERMAN, Fred J. ANDERSON, Huaiyi WANG
  • Publication number: 20210351879
    Abstract: Aspects described herein include a method comprising predicting, based on one or more transmission characteristics, error values for a sequence of bit positions used for modulating data within a packet. The method further comprises generating a bitmap that maps one or more payload bits and one or more padding bits of the packet to respective bit positions of the sequence. The one or more padding bits are preferentially mapped to respective bit positions having relatively greater error values. The method further comprises modulating the sequence according to the bitmap.
    Type: Application
    Filed: May 7, 2020
    Publication date: November 11, 2021
    Inventors: Huaiyi WANG, Brian D. HART, Matthew A. SILVERMAN, Zhigang GAO
  • Publication number: 20210223352
    Abstract: Embodiments herein describe performing AoA resolving to identify a plurality of AoAs corresponding to a multipath signal and then using AP voting to identify a location of the client device. AoA resolving enables an AP to identify the different angles at which a multipath signal reaches the AP. That is, due to reflections, a wireless signal transmitted by a single client device may reach the AP using multiple paths that each has their own AoA. The AP can perform AoA resolving to identify the AoAs for the different paths in a multipath signal. In one embodiment, the AoAs for two APs (or a subset of the APs) can be used to identify cross points or intersection points that represent candidate locations of the client device. A voting module can determine whether those cross points corresponds to AoAs identified by the remaining APs.
    Type: Application
    Filed: January 21, 2020
    Publication date: July 22, 2021
    Inventors: Zhigang GAO, Matthew A. SILVERMAN, Paul J. STAGER, Huaiyi WANG
  • Patent number: 11057121
    Abstract: In some embodiments, a method obtains raw data from one or more packets received over a wireless channel via an antenna. The raw data comprises raw amplitude values and raw phase values. Each raw amplitude value and raw phase value corresponds to a respective OFDM symbol and subcarrier of a respective packet. The method further comprises processing the raw data according to an interference mitigation process and using the resulting calibrated amplitude values and calibrated phase values to determine weighted phase values. Each weighted phase value corresponds to a respective subcarrier. The method determines a phase variance for the antenna based on comparing the plurality of weighted phase values across the plurality of subcarriers. The method determines whether the wireless channel experiences line-of-sight propagation or non-line-of-sight propagation based at least in part on the phase variance.
    Type: Grant
    Filed: September 9, 2019
    Date of Patent: July 6, 2021
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Huaiyi Wang, Zhigang Gao
  • Patent number: 10999738
    Abstract: Techniques for identification and isolation of Internet-of-Things devices in an enterprise network are described. In one embodiment, a method includes detecting a plurality of devices having a first network interface to connect to a wireless wide area network and a second network interface to connect to an enterprise network. The method also includes identifying a first subset of the plurality of devices as Internet-of-Things (IoT) devices based on at least a detected repetition rate on a physical random access channel of a transmission made by a device of the plurality of devices. The method includes assigning the IoT devices to a separate network segment within the enterprise network.
    Type: Grant
    Filed: January 28, 2019
    Date of Patent: May 4, 2021
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Santosh Ramrao Patil, Matthew Aaron Silverman, Huaiyi Wang, Gangadharan Byju Pularikkal, Akram Ismail Sheriff
  • Patent number: 10965349
    Abstract: In one embodiment, a method includes identifying a number of configured proactive repetitions in downlink transmissions from the base station, selecting k antenna states for receiving repetitive downlink transmissions among the number of antenna states, where k equals the number of configured proactive repetitions, and where each of the k antenna states corresponds to each of the repetitive downlink transmissions, transmitting a CSI report for each of the k antenna states to the base station, where a CSI report for an antenna state is used by the base station to adjust configurations for the corresponding downlink transmission, receiving signals for each of the k repetitive downlink transmissions from the base station using each of the k antenna states, and decoding the downlink transmission based on k sets of received signals, each of the k sets being received using each of the k selected antenna states.
    Type: Grant
    Filed: September 3, 2019
    Date of Patent: March 30, 2021
    Assignee: Cisco Technology, Inc.
    Inventors: Matthew Aaron Silverman, Fred J. Anderson, Ardalan Alizadeh, Huaiyi Wang
  • Publication number: 20210075534
    Abstract: A wireless node in a wireless communication network. The wireless node includes one or more interfaces configured to receive wireless transmissions, a memory comprising instructions, and a hardware processor. The wireless node samples a received wireless transmission into a plurality of time-based subdivisions. for each subdivision of the wireless transmission the wireless node determines a cross-correlation between the subdivision and a local syncword. The local syncword is constructed to correlate to any primary synchronization signal, PSS, of a plurality of PSSs defined for synchronization in the wireless network. The wireless node, based on the cross-correlation, determines whether one PSS of the plurality of PSSs is present in the subdivision of the wireless transmission.
    Type: Application
    Filed: September 6, 2019
    Publication date: March 11, 2021
    Inventors: Huaiyi Wang, Matthew Aaron Silverman, Zhigang Gao, Evgeny Yankevich
  • Publication number: 20210075523
    Abstract: In some embodiments, a method obtains raw data from one or more packets received over a wireless channel via an antenna. The raw data comprises raw amplitude values and raw phase values. Each raw amplitude value and raw phase value corresponds to a respective OFDM symbol and subcarrier of a respective packet. The method further comprises processing the raw data according to an interference mitigation process and using the resulting calibrated amplitude values and calibrated phase values to determine weighted phase values. Each weighted phase value corresponds to a respective subcarrier. The method determines a phase variance for the antenna based on comparing the plurality of weighted phase values across the plurality of subcarriers. The method determines whether the wireless channel experiences line-of-sight propagation or non-line-of-sight propagation based at least in part on the phase variance.
    Type: Application
    Filed: September 9, 2019
    Publication date: March 11, 2021
    Inventors: Huaiyi Wang, Zhigang Gao
  • Publication number: 20210067210
    Abstract: In one embodiment, a method includes identifying a number of configured proactive repetitions in downlink transmissions from the base station, selecting k antenna states for receiving repetitive downlink transmissions among the number of antenna states, where k equals the number of configured proactive repetitions, and where each of the k antenna states corresponds to each of the repetitive downlink transmissions, transmitting a CSI report for each of the k antenna states to the base station, where a CSI report for an antenna state is used by the base station to adjust configurations for the corresponding downlink transmission, receiving signals for each of the k repetitive downlink transmissions from the base station using each of the k antenna states, and decoding the downlink transmission based on k sets of received signals, each of the k sets being received using each of the k selected antenna states.
    Type: Application
    Filed: September 3, 2019
    Publication date: March 4, 2021
    Inventors: Matthew Aaron Silverman, Fred J. Anderson, Ardalan Alizadeh, Huaiyi Wang
  • Publication number: 20200245148
    Abstract: Techniques for identification and isolation of Internet-of-Things devices in an enterprise network are described. In one embodiment, a method includes detecting a plurality of devices having a first network interface to connect to a wireless wide area network and a second network interface to connect to an enterprise network. The method also includes identifying a first subset of the plurality of devices as Internet-of-Things (IoT) devices based on at least a detected repetition rate on a physical random access channel of a transmission made by a device of the plurality of devices. The method includes assigning the IoT devices to a separate network segment within the enterprise network.
    Type: Application
    Filed: January 28, 2019
    Publication date: July 30, 2020
    Inventors: Santosh Ramrao Patil, Matthew Aaron Silverman, Huaiyi Wang, Gangadharan Byju Pularikkal, Akram Ismail Sheriff
  • Publication number: 20200145830
    Abstract: In one embodiment, a method is performed. A classifier may receive a signal. The classifier may determine whether the signal passes a time-frequency filter. If the signal passes a time-frequency filter, the classifier may perform a search for at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and/or a demodulation reference signal (DMRS) in the signal. The classifier may classify the signal based on a result of the search.
    Type: Application
    Filed: November 5, 2018
    Publication date: May 7, 2020
    Inventors: Huaiyi Wang, Qing Zhao, Matthew Aaron Silverman
  • Patent number: D684895
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: June 25, 2013
    Inventors: Huaiyi Wang, Daoliang Wang