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: 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: 20220021560
    Abstract: Embodiments of a method and an apparatus for beamforming are disclosed. In an embodiment, a method for beamforming involves transmitting, by a beamformer to a beamformee, a sounding packet that includes training symbols, receiving, at the beamformee, the sounding packet that includes the training symbols, deriving, at the beamformee, channel estimates from the training symbols included in the sounding packet, computing, at the beamformee, a feedback matrix from the derived channel estimates, transmitting, by the beamformee to the beamformer, a packet that includes two sets of symbols, where the feedback matrix is applied to at least one of the two sets of symbols, receiving, at the beamformer, the packet that includes the two sets of symbols, and operating the beamformer according to the two sets of symbols included in the packet.
    Type: Application
    Filed: July 13, 2021
    Publication date: January 20, 2022
    Inventors: Sayak Roy, Ankit Sethi, 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
  • Patent number: 11229035
    Abstract: A method for transmitting a first physical layer (PHY) protocol data unit (PPDU) in a wireless local area network (WLAN) communication channel is described. One or more sectors of a service coverage area of a first communication device that are busy with a first transmission over the WLAN communication channel are identified. A second communication device is selected, using the identification of the one or more busy sectors, to receive the first PPDU during a second, directional transmission that at least partially temporally overlaps a duration of the first transmission. The first PPDU is generated for transmission to the second communication device. The first PPDU is transmitted to the second communication device as the second, directional transmission during the first transmission.
    Type: Grant
    Filed: December 6, 2019
    Date of Patent: January 18, 2022
    Assignee: Marvell Asia Pte Ltd
    Inventors: B Hari Ram, Vijay Ahirwar, Sri Varsha Rottela, Nilesh N. Khude, Sudhir Srinivasa
  • Publication number: 20220014238
    Abstract: Embodiments of a method and an apparatus for wireless communications are disclosed. In an embodiment, a method for wireless communications involves assigning subcarriers of a first access point (AP) and a second AP to a subcarrier set of a virtual AP, generating, by the virtual AP, a packet that includes a signal for a station (STA) and that is transmitted using the subcarrier set, where generating the packet includes: encoding a preamble portion of the packet on the assigned subcarriers included in the subcarrier set, nulling the preamble portion of the packet for unassigned subcarriers of the first AP and the second AP, encoding a subsequent portion of the packet according to a Distributed Multiple-Input Multiple-Output (DMIMO) transmission, and transmitting the packet to the STA.
    Type: Application
    Filed: July 7, 2021
    Publication date: January 13, 2022
    Inventors: Hari Ram Balakrishnan, Sudhir Srinivasa
  • Patent number: 11212705
    Abstract: Techniques for signaling new versions of a communication protocol differentiated from legacy versions of the communication protocol that are interoperable with stations implementing legacy versions of the communication protocol, that are compatible with future new versions of the communication protocol, and that do not overly complicate the receiver state machine have been disclosed.
    Type: Grant
    Filed: May 22, 2020
    Date of Patent: December 28, 2021
    Assignee: NXP USA, Inc.
    Inventors: Rui Cao, Hongyuan Zhang, Liwen Chu, Sudhir Srinivasa
  • Publication number: 20210399850
    Abstract: A first device transmits to a second device a first data unit which indicates a maximum number of long training field (LTF) symbols that the first device transmits and receives for a multiple input multiple output communication. The first device receives, from the second device, a second data unit which comprises a plurality of LTF symbols up to the maximum number of LTF symbols the first device receives indicated by the first data unit. A channel estimation is performed based on the plurality of LTF symbols of the second data unit up to the maximum number of LTF symbols indicated by the first data unit to recover information in one or more fields of the second data unit. For the case when the second data unit is a trigger frame, the first device generates the third data unit with a plurality of LTF symbols up to the maximum number of LTF symbols the first device transmits indicated by the first data unit and transmits the third data unit.
    Type: Application
    Filed: June 22, 2021
    Publication date: December 23, 2021
    Inventors: Yan Zhang, Sudhir Srinivasa, Hongyuan Zhang, Rui Cao
  • Publication number: 20210392661
    Abstract: Embodiments of a method and an apparatus for wireless communications are disclosed. In an embodiment, a method for wireless communications involves generating a Physical Layer Protocol Data Unit (PPDU) that includes a resource unit (RU), wherein a size of the RU is less than a signal bandwidth and wherein data corresponding to the RU is distributed onto a disjoint set of subcarriers included in a frequency unit, and transmitting the PPDU using the disjoint set of subcarriers in accordance with a power spectrum density (PSD) limit.
    Type: Application
    Filed: June 16, 2021
    Publication date: December 16, 2021
    Inventors: Rui Cao, Hongyuan Zhang, Yan Zhang, Liwen Chu, Hari Ram Balakrishnan, Sudhir Srinivasa
  • Publication number: 20210385115
    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: December 9, 2021
    Inventors: Rui Cao, Liwen Chu, Young Hoon Kwon, Hongyuan Zhang, SUDHIR SRINIVASA
  • Publication number: 20210360472
    Abstract: In an 802.11be wireless system, data units are generated for transmission by configuring a transmitting device to process encoding parameters, including a first encoding parameter NSD and a second encoding parameter NSD,short, to select a padding boundary from pre-defined padding boundaries in the last symbol that will most closely include the number of information bits NEXCESS in the last symbol and to append padding bits to the number of information bits NEXCESS to fill up to the selected padding boundary in the last symbol, thereby generating pre-encoded data bits which are encoded for data transmission, where at least the first encoding parameter NSD is specified for an aggregated resource unit size that is allowed under the 802.11be protocol as a sum of NSD values for at two other resource units.
    Type: Application
    Filed: May 12, 2021
    Publication date: November 18, 2021
    Applicant: NXP USA, Inc.
    Inventors: Rui Cao, Sudhir Srinivasa, Hongyuan Zhang, Mao Yu
  • Patent number: 11171696
    Abstract: Various embodiments relate to a method for processing received distributed multiple-input and multiple-output (DMIMO) OFDM signals from a plurality of transmitters, including: performing an initial carrier frequency offset (CFO) correction; receiving a plurality of OFDM symbols; re-constructing the channel every N symbols based upon a channel estimate for each transmitter and an estimate of residual CFO for each of the transmitters based upon the long term fields (LTF), wherein N is an integer; and equalizing the received OFDM symbols using the re-constructed channel.
    Type: Grant
    Filed: July 30, 2020
    Date of Patent: November 9, 2021
    Assignee: NXP USA, Inc.
    Inventors: Hari Ram Balakrishnan, Sri Varsha Rottela, Ankit Sethi, Vijay Ahirwar, Nilesh Nilkanth Khude, Sudhir Srinivasa
  • Patent number: 11165614
    Abstract: One example discloses an OFDM wireless communications device, including: a memory configured to support processing of OFDM tones; a controller, coupled to the memory, and configured to set the wireless communication device to a first mode and a second mode; wherein the first mode is configured to transmit or receive a first wireless communication signal having a first set of OFDM tones contained within an OFDM channel bandwidth; wherein the second mode is configured to transmit or receive a second wireless communication signal having a second set of OFDM tones contained within the OFDM channel bandwidth; and wherein the memory used for processing the first set of OFDM tones is same as the memory used for processing the second set of OFDM tones.
    Type: Grant
    Filed: November 16, 2020
    Date of Patent: November 2, 2021
    Assignee: NXP USA, Inc.
    Inventors: Sudhir Srinivasa, Yui Lin, Hongyuan Zhang, Mao Yu, Timothy J. Donovan
  • Patent number: 11166159
    Abstract: The present disclosure describes methods and apparatuses for secure fine timing measurement (FTM) with encoded long training fields (LTFs). In some aspects, a device transmits an announcement frame for an FTM exchange that includes an indication of encoding. Based on the indication of encoding, an LTF of a first null data packet (NDP) of the FTM exchange is encoded. The device transmits the first NDP having the encoded LTF to another device, and receives, from the other device, a second NDP having an encoded LTF. A round-trip time for the first and second NDPs with encoded LTFs is determined. Based on this round-trip time, a distance between the device and the other device can be determined. By encoding the LTFs of the NDPs of the FTM exchange, third parties can be prevented from spoofing an FTM frame to compromise the FTM exchange and related proximity-based security.
    Type: Grant
    Filed: June 11, 2018
    Date of Patent: November 2, 2021
    Assignee: Marvell Asia PTE, Ltd.
    Inventors: Christian Raimund Berger, Liwen Chu, Sudhir Srinivasa, Niranjan Grandhe
  • Publication number: 20210336752
    Abstract: Embodiments of a method and an apparatus for wireless communications are disclosed. In an embodiment, a method for wireless communications involves operating an Access Point (AP) using feedback subcarrier indices for a bandwidth up to 320 MHz, signaling, by the AP, to a client, a subcarrier location set on which a feedback report is solicited, signaling, by the AP, to a client, a feedback type solicited on the subcarrier location, and indicating, by the client, feedback subcarrier indices for the subcarrier location set via the feedback report solicited by the AP.
    Type: Application
    Filed: April 23, 2021
    Publication date: October 28, 2021
    Inventors: Young Hoon Kwon, Rui Cao, Liwen Chu, Hongyuan Zhang, Hari Ram Balakrishnan, Sudhir Srinivasa, Sayak Roy, Xiayu Zheng
  • Patent number: 11159348
    Abstract: Embodiments described herein provide a system for transmitting high efficiency long term training field (HE-LTF) symbols for multiple wireless spatial streams over a wireless channel. An advanced P-matrix design is used to construct HE-LTF symbols that are processed by a receiver such that channel properties such as channel estimates or carrier phase error are determined prior to receiving all HE-LTF symbols. Tone multiplexing of wireless spatial stream is also used to transmit multiple spatial streams based on an assignment of sets of spatial streams to sets of tones available for transmission, increasing the throughput of the transmission system. The advanced P-matrix design and tone multiplexing are used in combination to achieve calculate channel properties before receiving all HE-LTF symbols while minimizing power fluctuation among the high efficiency short training field symbol and the HE-LTF symbols.
    Type: Grant
    Filed: September 18, 2019
    Date of Patent: October 26, 2021
    Assignee: Marvell Asia Pte, Ltd.
    Inventors: Ankit Sethi, Sayak Roy, Hari Ram Balakrishnan, Sudhir Srinivasa
  • Publication number: 20210320763
    Abstract: Various embodiments relate to a method for transmitting a Wi-Fi signal using a channel of 80 MHz or wider, wherein each 80 MHz segment has a tone plan, including: determining that a physical 20 MHz sub-channel overlaps the 80 MHz segment or OFDMA transmission is used for the 80 MHz segment; selecting an alternative 80 MHz tone plan; and transmitting data on the 80 MHz segment using the selected alternative 80 MHz tone plan.
    Type: Application
    Filed: March 25, 2021
    Publication date: October 14, 2021
    Inventors: Rui Cao, Sudhir Srinivasa, Hongyuan Zhang