Patents by Inventor Sreevalsan Vallath

Sreevalsan Vallath 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: 9451497
    Abstract: A method for reducing packet loss during data transfer from a network to a wireless communication device over a connection is disclosed. The method can include the wireless communication device signaling a first receive window size for a data transfer; determining occurrence of an event resulting in an interruption of the connection; and, in response to determining occurrence of the event, signaling a second receive window size for the data transfer prior to the event to trigger an adjustment of a data rate of the data transfer in preparation for the event.
    Type: Grant
    Filed: August 13, 2013
    Date of Patent: September 20, 2016
    Assignee: Apple Inc.
    Inventors: Sarma V. Vangala, Sreevalsan Vallath, Swaminathan Balakrishnan, Vikram Bhaskara Yerrabommanahalli
  • Publication number: 20160249399
    Abstract: A method for offloading a video portion of a video call form a cellular network to a WLAN is provided. The method can include a wireless communication device participating in a video call with a remote device over a connection between the wireless communication device and a cellular network. The video call can include a first video stream carried over a first bearer on the cellular network and an audio stream carried over a second bearer on the cellular network. The method can further include the wireless communication device establishing a connection between the wireless communication device and a WLAN; performing a call setup procedure with the remote device to establish a second video stream over the WLAN; terminating the first video stream; and using the second video stream and the audio stream to continue the video call.
    Type: Application
    Filed: February 10, 2016
    Publication date: August 25, 2016
    Inventors: Samy KHAY-IBBAT, Sarma V. VANGALA, Paul V. FLYNN, Wen ZHAO, Sreevalsan VALLATH, Navid DAMJI
  • Patent number: 9426672
    Abstract: Methods and apparatus for network-based detection and mitigation of hybrid client device reception outage events. For example, in one embodiment, a cellular device uses a single-radio solution to support circuit-switched calls on a CDMA 1X network and packet-switched calls on LTE. Periodically, the cellular device tunes away from LTE and monitors CDMA 1X activity, and vice versa. During these tuned-away periods, the network adjusts operation to mitigate adverse effects (e.g., underutilization of radio resources, synchronization loss, etc.).
    Type: Grant
    Filed: March 26, 2013
    Date of Patent: August 23, 2016
    Assignee: Apple Inc.
    Inventors: Jianxiong Shi, Johnson O. Sebeni, Li Su, Navid Damji, Paul V. Flynn, Sarma V. Vangala, Sreevalsan Vallath, Thanigaivelu Elangovan, Zhu Ji
  • Patent number: 9420602
    Abstract: A radio resources management algorithm, through a process of function evaluation and optimization, determines and assigns resource priority values to wireless resource requests. Resource requests may be arranged within a priority queue in accordance with the priority values. The priority queue may control access to wireless resources that are typically reserved for handing off ongoing calls between cells. The algorithm may supplement or replace an existing CAC algorithm. The algorithm may also determine whether sufficient spare handoff resources are available to fulfill a resource request. If sufficient resources are not available, the disclosed algorithm may implement one or more congestion control mechanism designed to free up handoff resources. If sufficient resources are not available to fulfill a resource request, the resource request may be accepted and arranged in the priority queue if it is of sufficiently high priority, or may be rejected if the request is of low priority.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: August 16, 2016
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: Cagatay Buyukkoc, Sreevalsan Vallath
  • Publication number: 20160234750
    Abstract: Apparatus, system and methods for evaluating link quality within a cellular system. A user equipment (“UE”) is connected to a network, wherein the UE communicates data to the network on an uplink (“UL”) link. The UE determines a requested buffer size for a UL communication, determines a transport block size for the UL communication based on a primary set of allocation parameters, and compares the requested buffer size to the transport block size to determine if a data rate for the UL communication satisfies a threshold. When the data rate satisfies the threshold, the UE identifies the UL link as a good quality link and sends acceptable link quality feedback to the network. When the data rate does not satisfy the threshold, the UE performs a further action to test a quality of the UL link.
    Type: Application
    Filed: September 30, 2015
    Publication date: August 11, 2016
    Inventors: Navid DAMJI, Shivesh MAKHARIA, Luciano M. VERGER, Samy KHAY-IBBAT, Johnson O. SEBENI, Sree Ram KODALI, Sreevalsan VALLATH
  • Publication number: 20160226785
    Abstract: A method for initiating a codec rate change during a VoIP call by a wireless communication device is disclosed. The method can include the wireless communication device establishing a first codec rate for use in the VoIP call during a call establishment phase; using the first codec rate to encode voice data for transmission during a first portion of the VoIP call; determining a channel quality while using the first codec rate; determining that the channel quality satisfies a threshold for requesting a codec rate change; requesting a codec rate change from the first codec rate to a second codec rate in response to the channel quality satisfying the threshold; and using the second codec rate to encode voice data for transmission during a second portion of the VoIP call.
    Type: Application
    Filed: February 1, 2016
    Publication date: August 4, 2016
    Inventors: Samy KHAY-IBBAT, Sarma V. VANGALA, Sreevalsan VALLATH, Tarik TABET
  • Publication number: 20160219527
    Abstract: A user equipment and a method performed by the user equipment. The user equipment includes a transceiver configured to enable the user equipment to establish a connection with a first network and a second network, the first network configured to provide signals to control a transmit power of the transceiver and a processor configured to control the transmit power of the transceiver. The processor controls the transmit power by determining at least one network operation of the user equipment, the network operation associated with a configuration of the connection with the LTE network, receiving a signal from the LTE network indicating an increase in the transmit power to be used and performing a power operation that adjusts the transmit power of the transceiver less than the increase indicated in the signal.
    Type: Application
    Filed: January 23, 2015
    Publication date: July 28, 2016
    Inventors: Yingjie ZHAO, Li SU, Wanping ZHANG, Sreevalsan VALLATH
  • Publication number: 20160219518
    Abstract: A user equipment (UE) and corresponding methods to conserve power by the UE. The UE includes a transceiver, the transceiver configured to enable the UE to establish a connection with a Long Term Evolution (LTE) network and configured to operate using a Connected Discontinuous Reception (CDRX) functionality. The processor controls the transceiver by receiving an uplink (UL) grant at a first subframe of a frame of a cycle of the CDRX functionality, transmitting data based upon the UL grant at a predetermined second subframe, and receiving a response from the LTE network corresponding to one of an acknowledgement (ACK) and a negative ACK (NACK) at a predetermined third subframe. The processor deactivates the transmitter for a remainder of the frame based or deactivates a receiver for a remainder of the frame based upon whether the ACK is received.
    Type: Application
    Filed: January 23, 2015
    Publication date: July 28, 2016
    Inventors: Yingjie ZHAO, Li SU, Sreevalsan VALLATH, Wanping ZHANG
  • Patent number: 9374191
    Abstract: Outer loop link adaptation for device resumption. A user equipment (UE) and base station (BS) may be in communication in a first network (e.g., an LTE network). Communication between the UE and the BS may be interrupted, e.g., due to a long fading environment, the UE tuning away to a second network (e.g., a CDMA network). Accordingly, the measured error rate may increase dramatically. After resumption from the interruption, a negative offset may be applied to a reported SINR value from the UE due to the previous increase in error rate. Upon improvement in the error rate, a larger, positive offset adjustment may be added to the negative offset, allowing the estimated SINR to return to reported SINR more quickly. Additionally, the error rate estimation may be adjusted to converge to a more recently measured more quickly by decreasing a feedback filter coefficient.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: June 21, 2016
    Assignee: Apple Inc.
    Inventors: Tarik Tabet, Paul V. Flynn, Syed A. Mujtaba, Navid Damji, Zhu Ji, Sreevalsan Vallath
  • Patent number: 9338718
    Abstract: A method for resuming a voice call on a legacy network is provided. The method can include a wireless communication device establishing a voice call with a remote device over a first cellular network; determining that a connection quality of the first cellular network has dropped below a threshold connection quality; sending a notification that the wireless communication device is releasing the voice call to transition to a legacy cellular network and will resume the voice call on the legacy cellular network; releasing the voice call on the first cellular network; transitioning to the legacy cellular network; establishing a second voice call with the remote device on the legacy cellular network; and using the second voice call to resume the voice call with the remote device.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: May 10, 2016
    Assignee: Apple Inc.
    Inventors: Samy Khay-Ibbat, Sarma V. Vangala, Sreevalsan Vallath, Tarik Tabet
  • Patent number: 9307467
    Abstract: A network reselection procedure, of a wireless communication device, that occurs following a network detachment event, such as a device sleep event or a device power savings mode event. The wireless communication device attempts to acquire a first wireless network to which the wireless communication device was most recently attached, immediately preceding the network detachment event. Then, in response to an unsuccessful acquisition of the first wireless network, the wireless communication device attempts an alternate network acquisition utilizing a Most Recently Used List (MRUL) that is stored at the wireless communication device and includes information about one or more frequency bands allocated to a primary service provider with which the wireless communication device is affiliated. After determining whether the alternate network acquisition attempt was successful, the wireless communication device attaches to a second network and stores information associated with the second network.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: April 5, 2016
    Assignee: Apple Inc.
    Inventors: Swaminathan Balakrishnan, Sarma V. Vangala, Wanping Zhang, Tahir Shamim, Sreevalsan Vallath
  • Publication number: 20160073317
    Abstract: A method for transitioning a video call is provided. The method can include a wireless communication device participating in a video call with a remote communication device via a first video call session established over a connection between the wireless communication device and a first cellular network. The video call can include a packet switched video stream carried over a first bearer and an audio stream carried over a second bearer. The method can further include the wireless communication device determining a degradation in a connection quality for the first cellular network; transitioning to a legacy cellular network having a circuit switched domain in response to the degradation in connection quality for the first cellular network; establishing a second video call session on the legacy cellular network; and using the second video call session to continue the video call on the legacy cellular network.
    Type: Application
    Filed: November 17, 2015
    Publication date: March 10, 2016
    Inventors: Samy KHAY-IBBAT, Sarma V. VANGALA, Paul V. FLYNN, Wen ZHAO, Sreevalsan VALLATH, Navid DAMJI
  • Patent number: 9277176
    Abstract: A method for offloading a video portion of a video call form a cellular network to a WLAN is provided. The method can include a wireless communication device participating in a video call with a remote device over a connection between the wireless communication device and a cellular network. The video call can include a first video stream carried over a first bearer on the cellular network and an audio stream carried over a second bearer on the cellular network. The method can further include the wireless communication device establishing a connection between the wireless communication device and a WLAN; performing a call setup procedure with the remote device to establish a second video stream over the WLAN; terminating the first video stream; and using the second video stream and the audio stream to continue the video call.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: March 1, 2016
    Assignee: Apple Inc.
    Inventors: Samy Khay-Ibbat, Sarma V. Vangala, Paul V. Flynn, Wen Zhao, Sreevalsan Vallath, Navid Damji
  • Publication number: 20160044589
    Abstract: Systems and methods that enhance radio link performance in a multi-carrier environment. A method may be performed by a UE that includes scanning a plurality of carrier components for a primary cell, determining a first bandwidth of the primary cell, scanning for a secondary cell, determining a second bandwidth of the secondary cell, determining a maximum aggregated bandwidth by combining the first bandwidth and the second bandwidth and when the maximum aggregated bandwidth exceeds a bandwidth capability of the UE, performing a cell selection procedure to select one of the primary cell or the secondary cell based on a higher of the first bandwidth and the second bandwidth.
    Type: Application
    Filed: November 7, 2014
    Publication date: February 11, 2016
    Inventors: Sreevalsan Vallath, Deepankar Bhattacharjee, Navid Damji, Christian W. Mucke, Rafael L. Rivera-Barreto, Tarik Tabet
  • Patent number: 9253238
    Abstract: A method for initiating a codec rate change during a VoIP call by a wireless communication device is disclosed. The method can include the wireless communication device establishing a first codec rate for use in the VoIP call during a call establishment phase; using the first codec rate to encode voice data for transmission during a first portion of the VoIP call; determining a channel quality while using the first codec rate; determining that the channel quality satisfies a threshold for requesting a codec rate change; requesting a codec rate change from the first codec rate to a second codec rate in response to the channel quality satisfying the threshold; and using the second codec rate to encode voice data for transmission during a second portion of the VoIP call.
    Type: Grant
    Filed: September 30, 2013
    Date of Patent: February 2, 2016
    Assignee: Apple Inc.
    Inventors: Samy Khay-Ibbat, Sarma V. Vangala, Sreevalsan Vallath, Tarik Tabet
  • Publication number: 20160020983
    Abstract: Loading estimation of 3GPP networks. One or more metrics relating to a cell of a 3GPP network may be measured. Loading of the cell may be estimated based on the one or more metrics. The metrics may include metrics measured, estimated, or derived at multiple layers, possibly including one or more of physical layer, radio link control layer, radio resource control layer, or application layer metrics.
    Type: Application
    Filed: September 30, 2015
    Publication date: January 21, 2016
    Inventors: Sarma V. Vangala, Tarik Tabet, Swaminathan Balakrishnan, Yuchul Kim, Navid Damji, Sreevalsan Vallath, Samy Khay-Ibbat, Syed Aon Mujtaba
  • Publication number: 20160021563
    Abstract: QoS based uplink data buffering while TTI bundling is enabled by a wireless user equipment (UE) device. The UE may establish a packet-switched connection with a network via a wireless link. The UE may receive, at a media access control (MAC) layer, an indication to enable TTI bundling. The UE may selectively buffer uplink data at an application layer based on the indication to enable TTI bundling. The uplink data may be buffered selectively based on Quality of Service (QoS) considerations. Uplink transmissions may subsequently be performed using TTI bundling.
    Type: Application
    Filed: September 30, 2015
    Publication date: January 21, 2016
    Inventors: Samy Khay-Ibbat, Navid Damji, Sreevalsan Vallath, Sarma V. Vangala, Johnson O. Sebeni
  • Publication number: 20160021557
    Abstract: Estimating loading and potential available throughput a serving cell of a wireless user equipment (UE) device. Physical layer metrics of a channel on which the UE communicates with the serving cell may be measured. Cell utilization of the serving cell may be calculated based at least in part on the measured physical layer metrics. A maximum available throughput of the serving cell may be calculated based on the cell utilization.
    Type: Application
    Filed: September 30, 2015
    Publication date: January 21, 2016
    Inventors: Tarik Tabet, Sarma V. Vangala, Samy Khay-Ibbat, Swaminathan Balakrishnan, Ajoy K. Singh, Sree Ram Kodali, Rafael L. Rivera-Barreto, Syed Aon Mujtaba, Faraz Faheem, Sreevalsan Vallath
  • Patent number: 9215639
    Abstract: A method for transitioning a video call is provided. The method can include a wireless communication device participating in a video call with a remote communication device via a first video call session established over a connection between the wireless communication device and a first cellular network. The video call can include a packet switched video stream carried over a first bearer and an audio stream carried over a second bearer. The method can further include the wireless communication device determining a degradation in a connection quality for the first cellular network; transitioning to a legacy cellular network having a circuit switched domain in response to the degradation in connection quality for the first cellular network; establishing a second video call session on the legacy cellular network; and using the second video call session to continue the video call on the legacy cellular network.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: December 15, 2015
    Assignee: Apple Inc.
    Inventors: Samy Khay-Ibbat, Sarma V. Vangala, Paul V. Flynn, Wen Zhao, Sreevalsan Vallath, Navid Damji
  • Publication number: 20150351028
    Abstract: Methods and apparatus for reducing power consumption in a wireless device operating in a discontinuous transmission (DTX) mode while using a voice over Long Term Evolution (VoLTE) service. The wireless device detects a period of voice inactivity and transmits one or more silence descriptor (SID_UPDATE) frames to a second wireless device in place of encoded speech frames. The SID_UPDATE frames are transmitted periodically based on measurements of comfort noise parameters. The wireless device determines a difference between weighted averages of comfort noise (CN) parameters of two sequences of encoded speech frames. When the difference exceeds a difference threshold, a SID_UPDATE frame is transmitted. Additionally, in some embodiments, a SID_UPDATE frame is transmitted when the weighted average of CN parameters exceeds a parameter threshold and/or when a time between SID_UPDATE frames or time elapsed after entering a silence state exceeds one or more time thresholds.
    Type: Application
    Filed: September 25, 2014
    Publication date: December 3, 2015
    Inventors: Sreevalsan Vallath, Carola Faronius