Patents by Inventor Sudhir Srinivasa

Sudhir Srinivasa 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: 11463134
    Abstract: Wi-Fi communication is further secured by perturbation of a spatial mapping matrix. In an embodiment channel state information is obtained from a receiving device in a wireless network through the wireless network. A first set of beam steering vectors is derived based on the channel state information to direct a radio signal to the receiving device. A second set of beam steering vectors is derived based on the channel state information to direct a radio signal other than to the receiving device. A perturbation matrix is generated. A spatial mapping matrix is formed by combining the first and the second set of beam steering vectors with a perturbation matrix. Data symbols to be transmitted are pre-coded to the receiving device using the spatial mapping matrix and transmitted through the wireless network to the receiving device.
    Type: Grant
    Filed: February 11, 2021
    Date of Patent: October 4, 2022
    Assignee: NXP USA, INC.
    Inventors: Sayak Roy, Ankit Sethi, Sudhir Srinivasa
  • Patent number: 11463908
    Abstract: Some embodiments described herein provide a method for transmitting a preamble in accordance with a wireless local area network communication protocol. In some embodiments, a data frame may be obtained for transmission including a preamble compliant with the wireless local area network communication protocol. It may be determined that the preamble includes a first preamble portion that spans multiple symbol durations and a second preamble portion that spans a single symbol duration. The first preamble portion via beamforming may be transmitted based on a first beamforming matrix. When a transmission mode of the second preamble portion is beamforming, a second beamforming matrix may be generated based on the first beamforming matrix, each tone for the second preamble portion may be calculated based on the second beamforming matrix. Each calculated tone may be transmitted in accordance with the wireless local area network communication protocol.
    Type: Grant
    Filed: July 27, 2020
    Date of Patent: October 4, 2022
    Assignee: NXP USA, INC.
    Inventors: Yakun Sun, Hongyuan Zhang, Sudhir Srinivasa, Xiayu Zheng
  • Patent number: 11457448
    Abstract: A method and an apparatus for operating a Basic Service Set (BSS) are disclosed. A method involves announcing, by a first wireless device to a second wireless device, a BSS operating channel, wherein the first wireless device has at least one of a first transmission power capability and a first bandwidth capability, the second wireless device has at least one of a second transmission power capability that is less than the first transmission power capability and a second bandwidth capability that is narrower than the first bandwidth capability, and wherein the BSS operating channel is at least one of a punctured operating channel and an unpunctured operating channel, associating, by the second wireless device, with the first wireless device via the announcement of the BSS operating channel from the first wireless device, and exchanging frames between the first wireless device and the second wireless device in the BSS operating channel.
    Type: Grant
    Filed: February 22, 2021
    Date of Patent: September 27, 2022
    Assignee: NXP USA, Inc.
    Inventors: Liwen Chu, Rui Cao, Sudhir Srinivasa, Hongyuan Zhang, Huiling Lou, Young Hoon Kwon
  • Patent number: 11452063
    Abstract: A first communication device determines which one or more types of feedback information, from among a plurality of types of feedback information associated with a range measurement exchange session, a second communication device is to provide to the first communication device in a feedback packet transmitted as part of the range measurement exchange session. The first communication device transmits to the second communication device one or more indications of the determined one or more types of feedback information that the second communication device is to provide to the first communication device in the feedback packet. The first communication device performs the range measurement exchange, including receiving the feedback packet from the second communication device, wherein the feedback packet includes the determined one or more types of feedback information.
    Type: Grant
    Filed: December 22, 2020
    Date of Patent: September 20, 2022
    Assignee: Marvell Asia Pte Ltd
    Inventors: Liwen Chu, Hongyuan Zhang, Christian R. Berger, Niranjan Grandhe, Sudhir Srinivasa, Hui-Ling Lou
  • Patent number: 11431389
    Abstract: A beamformer generates a null data packet (NDP) that includes various long training fields (LTFs). The beamformer generates the NDP based on a spatial mapping matrix that is a product of two matrices. One matrix has a number of rows equal to a number of antennas of the beamformer, and a number of columns equal to a number of LTFs in the NDP. Further, the other matrix has a number of rows and a number of columns equal to the number of LTFs in the NDP. The number of LTFs in the NDP is greater than a number of antennas of the beamformer. Further, the beamformer transmits the NDP to a beamformee to obtain channel state information associated with a channel between the beamformer and the beamformee, and enable beamforming therebetween.
    Type: Grant
    Filed: July 10, 2021
    Date of Patent: August 30, 2022
    Assignee: NXP USA, Inc.
    Inventors: Ankit Sethi, Sayak Roy, Sudhir Srinivasa
  • Publication number: 20220255590
    Abstract: Wi-Fi communication is further secured by perturbation of a spatial mapping matrix. In an embodiment channel state information is obtained from a receiving device in a wireless network through the wireless network. A first set of beam steering vectors is derived based on the channel state information to direct a radio signal to the receiving device. A second set of beam steering vectors is derived based on the channel state information to direct a radio signal other than to the receiving device. A perturbation matrix is generated. A spatial mapping matrix is formed by combining the first and the second set of beam steering vectors with a perturbation matrix. Data symbols to be transmitted are pre-coded to the receiving device using the spatial mapping matrix and transmitted through the wireless network to the receiving device.
    Type: Application
    Filed: February 11, 2021
    Publication date: August 11, 2022
    Inventors: Sayak ROY, Ankit SETHI, Sudhir SRINIVASA
  • Patent number: 11405078
    Abstract: A beamformee executes a singular value decomposition operation on a channel coefficient matrix to generate a diagonal matrix and a unitary matrix. The beamformee extracts a submatrix from each of the diagonal matrix and the unitary matrix. Each of a number of rows and a number of columns of the submatrix extracted from the diagonal matrix is equal to a number of spatial streams associated with a beamformer. Further, the submatrix extracted from the unitary matrix has a number of rows and a number of columns equal to a number of beamformer antennas of the beamformer and the number of spatial streams, respectively. The beamformee generates a subspace matrix that is a product of the submatrix extracted from the diagonal matrix and a conjugate transpose of the submatrix extracted from the unitary matrix. Further, the beamformee generates a steering matrix based on the subspace matrix.
    Type: Grant
    Filed: August 24, 2021
    Date of Patent: August 2, 2022
    Assignee: NXP USA, Inc.
    Inventors: Sayak Roy, Ankit Sethi, Sudhir Srinivasa
  • Patent number: 11405075
    Abstract: A first access point (AP) for enabling distributed multiple-input-multiple-output (DMIMO) communication in a wireless network is disclosed. The first AP is configured to select a wireless client from a plurality of wireless clients or a second AP from a plurality of APs such that a difference between a path loss value associated with the first AP and the wireless client, and a path loss value associated with the second AP and the wireless client is greater than or equal to a threshold value. The wireless client is selected when the first and second APs are available for DMIMO communication, and the second AP is selected when the wireless client and the first AP are available for DMIMO communication. The first AP is further configured to associate the first and second APs with the wireless client for enabling DMIMO communication between the first and second APs and the wireless client.
    Type: Grant
    Filed: July 14, 2020
    Date of Patent: August 2, 2022
    Assignee: NXP USA, INC.
    Inventors: Hari Ram Balakrishnan, Sudhir Srinivasa
  • Patent number: 11405171
    Abstract: A method for controlling communication of information includes selecting a group of stations within range of an access point, transmitting a first signal from the access point to a first station in the group, and receiving at the access point a second signal from a second station in the group. The first signal is transmitted to the first station through a downlink channel. The second signal is received from the second station through an uplink channel. Transmission of the first signal takes place during a first period and reception of the second signal takes place during a second period overlapping the first period, in order to perform full-duplex different-frequency communications based on an 802.11 standard between the access point and the first station and the second station.
    Type: Grant
    Filed: February 21, 2020
    Date of Patent: August 2, 2022
    Assignee: NXP B.V.
    Inventors: Nilesh Nilkanth Khude, Vijay Ahirwar, Hari Ram Balakrishnan, Sri Varsha Rottela, Ankit Sethi, Sudhir Srinivasa
  • Patent number: 11395359
    Abstract: A first aggregated MAC protocol data unit (A-MPDU) is generated for transmission over a first frequency segment of a communication channel, and a second A-MPDU is generated for transmission over a second frequency segment of the communication channel. A PHY protocol data unit (PPDU) is generated to include the plurality of A-MPDUs and a second PPDU is generated to include the second A-MPDU. A first transmit processor generates a first RF signal for transmission of the first PPDU over the first frequency segment and a second transmit processor generates a second RF signal for transmission of the second PPDU over the second frequency segment. The first RF signal is transmitted in the first frequency segment simultaneously with the second RF signal being transmitted in the second frequency segment.
    Type: Grant
    Filed: April 13, 2020
    Date of Patent: July 19, 2022
    Assignee: Marvell Asia Pte Ltd
    Inventors: Rui Cao, Hongyuan Zhang, Sudhir Srinivasa
  • Publication number: 20220217027
    Abstract: One example discloses an IEEE 802.11 compliant wireless communications device, including: a processor configured to generate a hybrid-physical protocol data unit (hybrid-PPDU) that includes a set of sub-PPDUs; a first sub-PPDU in the set of sub-PPDUs includes a first preamble portion and a first data payload portion; a second sub-PPDU in the set of sub-PPDUs includes a second preamble portion and a second data payload portion; wherein an OFDMA communications signal includes a set of symbol tones divided into a set of resource units (RUs); wherein the processor is configured to map the first sub-PPDU to a first RU within the set of RUs, and map the second sub-PPDU to a second RU within the set of RUs; and wherein the first preamble portion corresponds to a first 802.11 packet format, and the second preamble portion corresponds to a second 802.11 packet format.
    Type: Application
    Filed: February 22, 2021
    Publication date: July 7, 2022
    Inventors: Rui Cao, Liwen Chu, Young Hoon Kwon, Hongyuan Zhang, SUDHIR SRINIVASA
  • Patent number: 11381441
    Abstract: A millimeter-wave communication system includes a transmitter and a receiver. The transmitter is configured to be connected to a waveguide that is transmissive at millimeter-wave frequencies, the waveguide having a propagation parameter that varies with frequency at the millimeter-wave frequencies. The transmitter is configured to generate a millimeter-wave signal comprising multiple sub-carriers that are modulated with data, wherein each sub-carrier is modulated with a respective portion of the data and is subjected to only a respective fraction of a variation in the propagation parameter, and to transmit the millimeter-wave signal into a first end of the waveguide. The receiver is configured to receive the millimeter-wave signal from a second end of the waveguide, and to extract the data from the multiple sub-carriers.
    Type: Grant
    Filed: July 31, 2019
    Date of Patent: July 5, 2022
    Assignee: NXP USA, Inc.
    Inventors: Sai-Wang Tam, Su Chenxin, Vijay Ahirwar, Rulin Huang, Alden C. Wong, Rui Cao, Sudhir Srinivasa, Alireza Razzaghi, Randy Tsang, Timothy J. Donovan
  • Patent number: 11374683
    Abstract: A communication device generates a legacy portion of a physical layer (PHY) preamble of a PHY data unit. The legacy portion includes a plurality of legacy training fields and a legacy signal field that indicates a duration of the PHY data unit. The communication device generates a non-legacy portion of the PHY preamble to include a multi-bit signal field header to indicate a packet type of the PHY data unit from among a plurality of packet types defined by a wireless communication protocol, the plurality of packet types corresponding to a plurality of non-legacy signal field formats. The communication device generates a non-legacy portion of the PHY preamble to also include a non-legacy signal field having a field format i) selected from the plurality of non-legacy signal field formats and ii) consistent with the packet type indicated by the multi-bit signal field header.
    Type: Grant
    Filed: December 4, 2019
    Date of Patent: June 28, 2022
    Assignee: Marvell Asia Pte Ltd
    Inventors: B Hari Ram, Vijay Ahirwar, Sri Varsha Rottela, Hongyuan Zhang, Sudhir Srinivasa, Nilesh Khude
  • Publication number: 20220124727
    Abstract: A first communication device in a first WLAN determines a channel estimate of a communication channel between the first communication device and a second communication device in a second WLAN using measurements at the first communication device of a first transmission between the second communication device and a third communication device in the second WLAN. The first communication device generates a PPDU for transmission to a fourth communication device in the first WLAN, including: determining, using the channel estimate, a precoder matrix to use for transmitting the PPDU in the first WLAN, and generating the PPDU using the precoder matrix so that interference at the second communication device in the second WLAN caused by transmission of the PPDU by the first communication device in the first WLAN is reduced. The first communication device transmits the PPDU to the fourth communication device in the first WLAN as a directional second transmission.
    Type: Application
    Filed: December 30, 2021
    Publication date: April 21, 2022
    Inventors: B Hari RAM, Vijay AHIRWAR, Sri Varsha ROTTELA, Nilesh N. KHUDE, Sudhir SRINIVASA
  • Patent number: 11309998
    Abstract: A first communication device generates and transmits a first physical layer (PHY) data unit as part of a hybrid automatic repeat request (HARQ) session, the first PHY data unit having a first plurality of media access control (MAC) protocol data units (MPDUs) including a first MPDU. The first communication device determines that a second communication device did not acknowledge successfully receiving the first MPDU. The first communication device generates and transmits a second PHY data unit as part of the HARQ session, the second PHY data unit having a second plurality of MPDUs, the second plurality of MPDUs including the first MPDU.
    Type: Grant
    Filed: August 27, 2020
    Date of Patent: April 19, 2022
    Assignee: NXP USA, INC.
    Inventors: Yakun Sun, Liwen Chu, Hongyuan Zhang, Sudhir Srinivasa, Huiling Lou
  • Publication number: 20220116179
    Abstract: Various embodiments relate to a method of sounding a plurality of stations (STAs) with mixed operating bandwidths using a null data packet (NDP), wherein the bandwidth of the NDP is wider than the bandwidth of one STA, including: grouping STAs of mixed operating bandwidth in one sounding sequence by a beamformer; transmitting a null data packet announcement (NDPA) to the STAs, wherein the NDPA indicates the requested partial bandwidth channel feedback for each STA by the beamformer; transmitting the wide-bandwidth NDP to the STAs by the beamformer; transmitting beamforming report poll (BFRP) frame to the STAs to trigger uplink transmission of channel feedback reports by the beamformer; and receiving by the beamformer a partial bandwidth channel feedback within the STA's operating bandwidth from the STAs; receiving and parsing channel feedback reports from the STAs used for following steered OFDMA transmissions by the beamformer.
    Type: Application
    Filed: October 6, 2021
    Publication date: April 14, 2022
    Inventors: Rui CAO, Sudhir Srinivasa, Xiayu Zheng, Hongyuan Zhang
  • Publication number: 20220029872
    Abstract: In an 802.11be wireless system, a receiving station device signals a packet padding capability in a wireless area network in accordance with an Extremely High Throughput (EHT) communication protocol by constructing a MAC control management frame to include an EHT capability element indicating whether a packet extension value longer than 16 ?s is supported by the receiving station device, where one or more fields in the EHT capability element include (1) a common nominal packet padding field having a plurality of values to signal different packet extension values for use with all transmission constellations, spatial streams Nss, and resource unit (RU) allocations supported by the first STA device, including at least one packet extension value longer than 16 ?s; and/or (2) a PHY packet extension threshold (PPET) field comprising a plurality of PPET values to signal packet extension values including at least one packet extension value longer than 16 ?s.
    Type: Application
    Filed: July 27, 2021
    Publication date: January 27, 2022
    Applicant: NXP USA, Inc.
    Inventors: Rui Cao, Sudhir Srinivasa, Hongyuan Zhang, Liwen Chu
  • Patent number: 11233625
    Abstract: A method for signal transmission includes generating a sequence of modulated symbols, each modulated symbol including multiple sub-carriers having respective sub-carrier frequencies, by (i) designating a first subset of the sub-carriers to serve as non-pilot sub-carriers, and designating a second subset of the sub-carriers to serve as pilot sub-carriers, (ii) modulating non-pilot information onto the non-pilot sub-carriers, and modulating pilot information onto the pilot sub-carriers, and (iii) in at least some of the symbols, setting the non-pilot sub-carriers to a first power level, and setting one or more of the pilot sub-carriers to a second power level that is higher than the first power level. The sequence of the modulated symbols is transmitted over a communication channel to a receiver.
    Type: Grant
    Filed: October 3, 2019
    Date of Patent: January 25, 2022
    Assignee: NXP USA, Inc.
    Inventors: Ankit Sethi, Sudhir Srinivasa, Sayak Roy
  • Publication number: 20220021416
    Abstract: A first access point (AP) for enabling distributed multiple-input-multiple-output (DMIMO) communication in a wireless network is disclosed. The first AP is configured to select a wireless client from a plurality of wireless clients or a second AP from a plurality of APs such that a difference between a path loss value associated with the first AP and the wireless client, and a path loss value associated with the second AP and the wireless client is greater than or equal to a threshold value. The wireless client is selected when the first and second APs are available for DMIMO communication, and the second AP is selected when the wireless client and the first AP are available for DMIMO communication. The first AP is further configured to associate the first and second APs with the wireless client for enabling DMIMO communication between the first and second APs and the wireless client.
    Type: Application
    Filed: July 14, 2020
    Publication date: January 20, 2022
    Inventors: Hari Ram Balakrishnan, Sudhir Srinivasa
  • Publication number: 20220021559
    Abstract: Embodiments of a method and an apparatus for wireless communications are disclosed. In an embodiment, a method for wireless communications involves generating a packet for transmission to a user, where generating the packet includes: encoding user signaling parameters and setting a station-identification (STA-ID) of the user to a value, where the signaling parameters include a number of space time streams (nSTS) spatial streams, establishing a dummy user without changing the user signaling parameters, setting a STA-ID of the dummy user to a value that is different from the STA-ID value of the user, indicating the nSTS spatial streams that are allocated to the dummy user and that are to include Long Training Field (LTF) symbols, and transmitting the packet to the user with the LTF symbols.
    Type: Application
    Filed: July 7, 2021
    Publication date: January 20, 2022
    Inventors: Ankit Sethi, Sayak Roy, Sudhir Srinivasa