Patents by Inventor Syed A Mujtaba

Syed A Mujtaba 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: 20130315119
    Abstract: A method is disclosed for coordinating a user equipment's communication with a network during tune back with C-DRX (connected mode discontinuous receive). When a user equipment tunes back to a network after a tune away or a signal fade, a scheduling request is sent to the network to indicate the tune back as quickly as possible. The user equipment waits for a downlink transmission from the network. When the user equipment does not receive the downlink transmission, the method determines if the connection between the user equipment and the network has been released. The sending of the first scheduling request and any additional scheduling requests is coordinated with the C-DRX configuration so as to maximize the battery savings of C-DRX and minimize the latency of the tune back process in case the user equipment has uplink data to send.
    Type: Application
    Filed: August 31, 2012
    Publication date: November 28, 2013
    Applicant: Apple Inc.
    Inventors: Tarik TABET, Paul V. Flynn, Sreevalsan Vallath, Kee-Bong Song, Syed A. Mujtaba, Li Su
  • Publication number: 20130310057
    Abstract: Various embodiments are disclosed of a method and apparatus for fast communication recovery in wireless mobile devices arranged to perform dual network radio resource management. In one embodiment, a wireless mobile device includes a transceiver configured to communicate with each of first and second networks. After establishing and maintaining a link with the first network, the wireless mobile device may tune a transceiver to the second network to monitor for traffic, subsequently tuning back to the first network. After turning the transceiver back to the first network, the wireless mobile device may perform one or more attempts to restore the link to the first network. The number of attempts to restore the link is dependent upon an amount of time the transceiver is tuned to the second network.
    Type: Application
    Filed: September 19, 2012
    Publication date: November 21, 2013
    Applicant: APPLE INC.
    Inventors: Tarik Tabet, Syed A. Mujtaba, Kee-bong Song
  • Publication number: 20130310092
    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: Application
    Filed: October 30, 2012
    Publication date: November 21, 2013
    Applicant: APPLE INC.
    Inventors: Tarik Tabet, Paul V. Flynn, Syed A. Mujtaba, Navid Damji, Zhu Ji, Sreevalsan Vallath
  • Publication number: 20130310091
    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: Application
    Filed: September 7, 2012
    Publication date: November 21, 2013
    Inventors: Tarik Tabet, Paul V. Flynn, Syed A. Mujtaba, Navid Damji, Zhu Ji, Sreevalsan Vallath
  • Publication number: 20130272212
    Abstract: Managing radio resources across dual networks includes a wireless mobile device connecting to a first wireless network using a first radio access technology. The wireless device may notify the first network of a capability to be temporarily non-responsive to the first network while maintaining a signaling connection to the first network. The wireless device may communicate with a second network. The wireless device may return to communicating with the first network subsequent to communicating with the second network, and in response to communicating with the second network for less than a predetermined amount of time, the wireless device may send a scheduling request to the first network. In response to receiving a grant acknowledgement from the first network, the wireless device may send a buffer status report that includes a value such as zero to indicate that the wireless device has returned to and can communicate with the first network.
    Type: Application
    Filed: August 30, 2012
    Publication date: October 17, 2013
    Inventors: Tarik Tabet, Syed A. Mujtaba, Xiaowen Wang, Paul Flynn, Kee-Bong Song, Vinay Majjigi, Youngjae Kim, Yuchul Kim, Christian Mucke
  • Publication number: 20130250785
    Abstract: A user device receives packets from a base station. The user device may invoke decoding while the packet is still being received, based on the incomplete contents of a given packet. This “partial packet decoding” relies on the fact that the underlying information in the packet is encoded with redundancy (code rate less than one). If link quality is poor, the partial packet decoding is likely to be unsuccessful, i.e., to fail in its attempt to recover the underlying information. To avoid waste of power, the user device may be configured to apply one or more tests of link quality prior to invoking the partial packet decoding on a current packet.
    Type: Application
    Filed: August 6, 2012
    Publication date: September 26, 2013
    Inventors: Syed A. Mujtaba, Kee-Bong Song, Yuchul Kim, Xiaowen Wang, Tarik Tabet, Youngjae Kim
  • Publication number: 20130242779
    Abstract: Methods and apparatus for interference coordination to improve transmission and reception performance within wireless networks. In one exemplary embodiment, a wireless transmitter transmits multiple transmissions over a determined time. The receiver receives the multiple transmissions and attempts to recover the transmitted signal. Because, the fading channel varies over time for each transmitter-receiver, by combining the received signals over multiple iterations, the signal of interest will be magnified, whereas interference effects will be suppressed.
    Type: Application
    Filed: March 6, 2013
    Publication date: September 19, 2013
    Applicant: Apple Inc.
    Inventors: Seyed Reza Mir Ghaderi, Kee-Bong Song, Syed A. Mujtaba
  • Patent number: 8498656
    Abstract: Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. An electronic device may alternate between a sleep mode and a wake mode. During wake mode, the electronic device may monitor a paging channel in a wireless network for incoming paging signals. The device may use a selected one of the multiple antennas in monitoring the paging channel. If received signal quality is satisfactory, the device may maintain use of the selected one of the multiple antennas for subsequent wake period monitoring of the paging channel. If received signal quality falls below a threshold or is otherwise indicated to not be satisfactory, the device may switch to use of a different one of the multiple antennas in monitoring the paging channel. Other criteria may also be used in controlling the switching between antennas for paging channel monitoring.
    Type: Grant
    Filed: May 2, 2011
    Date of Patent: July 30, 2013
    Assignee: Apple Inc.
    Inventors: Syed A. Mujtaba, Kee-Bong Song, Youngjae Kim
  • Publication number: 20130064151
    Abstract: A mobile wireless device adapts receive diversity during discontinuous reception based on downlink signal quality, page indicators and page messages. When the downlink signal quality exceeds a pre-determined threshold, the mobile wireless device decodes a page indicator channel through an initial antenna, and otherwise, decodes a paging channel through the initial antenna without decoding the page indicator channel. The mobile wireless device switches to decoding the paging channel through an alternate antenna when a page indicator decodes as an erasure. When a paging message received through a single antenna decodes with an incorrect error checking code, the mobile wireless devices enables receive diversity through multiple antennas for subsequent decoding. The mobile wireless device switches between single antenna reception and multiple antenna reception based on tracking multiple consecutive error checking code failures and successes.
    Type: Application
    Filed: September 13, 2011
    Publication date: March 14, 2013
    Applicant: Apple Inc.
    Inventors: Syed A. Mujtaba, Kee-Bong Song, Xiaowen Wang, Young Jae Kim, Vinay R. Majjigi, Johnson O. Sebeni, Romain Trilling, Tahir Shamim, Karthik Anantharaman
  • Publication number: 20130033996
    Abstract: Electronic devices may be provided that contain wireless communications circuitry capable of supporting time division multiple access. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. Signal strength measurements may be gathered using the antennas and corresponding signal strength difference measurements may be computed to reflect which of the antennas is exhibiting superior performance. The signal strength measurements may be made by measuring receive power levels in a beacon channel during idle time slots while toggling its antennas in and out of use or by detecting for the presence of non-silent traffic channel frames or silence indicator description frames and measuring corresponding receive power levels while toggling its antennas in and out of use.
    Type: Application
    Filed: August 5, 2011
    Publication date: February 7, 2013
    Inventors: Kee-Bong Song, Syed A. Mujtaba
  • Publication number: 20130035051
    Abstract: Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. Signal strength measurements may be gathered using the antennas and corresponding signal strength difference measurements may be produced to reflect which of the antennas is exhibiting superior performing. The signal strength difference measurements may be filtered using time-based averaging filters with different speeds. Corresponding filtered difference measurements may be compared to antenna switching criteria such as antenna switching thresholds. An antenna switching threshold may be adjusted in real time based on computations of how much variation is exhibited as a function of time between the difference measurements filtered using the filters of different speeds. Information on device movement or other data may be used in making threshold adjustments.
    Type: Application
    Filed: August 1, 2011
    Publication date: February 7, 2013
    Inventors: Syed A. Mujtaba, Kee-Bong Song
  • Publication number: 20130035084
    Abstract: A mobile wireless device adapts transmit power levels and number of retransmissions of a preamble sent to a wireless network. The mobile wireless device measures characteristics of a downlink signal received from the wireless network. The mobile wireless device transmits a series of preambles to the wireless network, each successive preamble having an increased power level, starting at a power level based on the measured received signal characteristics and on parameters received from the wireless network, up to a maximum transmit power level. When the transmit power level of the preamble exceeds the maximum transmit power level and when the measured downlink signal quality falls below a threshold, the mobile wireless device limits the number of preamble retransmission to less than an allowed maximum number of retransmissions. A minimum number of retransmissions is determined and adapted to higher values for larger measured values of downlink signal quality.
    Type: Application
    Filed: July 21, 2012
    Publication date: February 7, 2013
    Applicant: Apple Inc.
    Inventors: KEE-BONG SONG, Xiaowen Wang, Syed A. Mujtaba
  • Publication number: 20130035103
    Abstract: Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to first and second antennas. An electronic device may send network access probe signals to a base station in a wireless network. If the base station responds with a corresponding acknowledgement, the electronic device and base station may establish a wireless communication link such as a cellular telephone link. In response to failure to receive the acknowledgement signal from the base station, the electronic device may increase the transmit power of a successive network access probe signal. The electronic device may switch between use of the first and second antennas when transmitting the network access probe signals. The electronic device may alternate between the first and second antennas or may use other antenna usage patterns.
    Type: Application
    Filed: August 1, 2011
    Publication date: February 7, 2013
    Inventors: Syed A. Mujtaba, Youngjae Kim, Kee-Bong Song, Xiaowen Wang
  • Publication number: 20130016632
    Abstract: A wireless electronic device having first and second baseband processors is provided. In one suitable arrangement, radio-frequency power splitters and adjustable low noise amplifiers may be form in the receive paths. The use of power splitters allow signals associated with the first and second baseband processors to be received in parallel. In another suitable arrangement, radio-frequency switches are used in place of the power splitters. The states of the switches may be controlled using at least one of the first and second baseband processors. The use of switches instead of power splitters requires that wake periods associated with the first baseband processor and wake periods associated with the second baseband processor are non-overlapping. To ensure minimal wake period collision, a wake period associated with the second baseband processor may be positioned at a midpoint between two successive wake periods associated with the first baseband processor.
    Type: Application
    Filed: January 11, 2012
    Publication date: January 17, 2013
    Inventors: Syed A. Mujtaba, Madhusudan Chaudhary, Thanigaivelu Elangovan, Karthik Anantharaman, Weiping Dou, Isabel G. Mahe
  • Publication number: 20120282975
    Abstract: Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to antennas. An electronic device may include a baseband processor and other storage and processing circuitry that implements protocol stacks for handling multiple radio access technologies. The storage and processing circuitry may use the transceiver circuitry to convey data using a first radio access technology while periodically interrupting the conveying of the data to monitor a paging channel using a second radio access technology. In performing the paging channel monitoring operations, the storage and processing circuitry may enforce a time limit that ensures that operations using the first radio access technology are not disrupted more than desired.
    Type: Application
    Filed: May 2, 2011
    Publication date: November 8, 2012
    Inventors: Syed A. Mujtaba, Wen Zhao, Xiaowen Wang, Vinay Majjigi
  • Publication number: 20120281553
    Abstract: Electronic devices may be provided that contain wireless communications circuitry. The wireless communications circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. An electronic device may alternate between a sleep mode and a wake mode. During wake mode, the electronic device may monitor a paging channel in a wireless network for incoming paging signals. The device may use either a single antenna mode or a multiple antenna mode such as a dual antenna mode in monitoring the paging channel. In the single antenna mode, a single active antenna is used to receive paging signals. In the dual antenna mode two antennas are simultaneously used to receive paging signals. The device may choose which antenna mode to use based on signal quality measurements and history information on successfully received paging signals.
    Type: Application
    Filed: May 2, 2011
    Publication date: November 8, 2012
    Inventors: Syed A. Mujtaba, Youngjae Kim, Bharath Narasimha Rao, Kee-Bong Song, Xiaowen Wang
  • Publication number: 20120282982
    Abstract: Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to multiple antennas. An electronic device may alternate between a sleep mode and a wake mode. During wake mode, the electronic device may monitor a paging channel in a wireless network for incoming paging signals. The device may use a selected one of the multiple antennas in monitoring the paging channel. If received signal quality is satisfactory, the device may maintain use of the selected one of the multiple antennas for subsequent wake period monitoring of the paging channel. If received signal quality falls below a threshold or is otherwise indicated to not be satisfactory, the device may switch to use of a different one of the multiple antennas in monitoring the paging channel. Other criteria may also be used in controlling the switching between antennas for paging channel monitoring.
    Type: Application
    Filed: May 2, 2011
    Publication date: November 8, 2012
    Inventors: Syed A. Mujtaba, Kee-Bong Song, Youngjae Kim
  • Publication number: 20120270545
    Abstract: A single chip mobile wireless device capable of receiving and transmitting over one wireless network at a time maintains registration on two wireless communication networks that each use different communication protocols in parallel. Periodically, the mobile wireless device tunes one or more receivers from a first wireless network to a second wireless network in order to listen for paging messages addressed to the mobile wireless device from the second wireless network. The first wireless network suspends allocation of radio resources to the mobile wireless device based on receipt of a suspension message from the mobile wireless device, or based on knowledge of a paging cycle for mobile wireless device in the second wireless network, or based on detection of an out of synchronization condition with the mobile wireless device.
    Type: Application
    Filed: March 9, 2012
    Publication date: October 25, 2012
    Applicant: Apple Inc.
    Inventors: Wen ZHAO, Syed A. Mujtaba, Xiaowen Wang, Vinay R. Majjigi, Isabel G. Mahe
  • Publication number: 20120264473
    Abstract: Electronic devices may be provided that contain wireless communication circuitry. The wireless communication circuitry may include radio-frequency transceiver circuitry coupled to antennas by switching circuitry. Multiple radio access technologies may be supported. A device may include first and second antennas. Control circuitry can configure the transceiver circuitry and switching circuitry to support operation of the device in active and idle modes for each radio access technology. In some configurations, both antennas may be used to support operations associated with one of the radio access technologies. In other configurations, the first antenna may be used to support operations with a first of the radio access technologies while the second antenna is used to support operations with a second of the radio access technologies.
    Type: Application
    Filed: August 1, 2011
    Publication date: October 18, 2012
    Inventors: Syed A. Mujtaba, Wen Zhao, Xiaowen Wang, Vinay Majjigi, Isabel G. Mahe
  • Publication number: 20120184228
    Abstract: Electronic devices may have multiple wireless integrated circuits such as a pair of baseband processor integrated circuits and may have multiple antennas such as a pair of antennas. An electronic device may be operated in different modes depending on the operating environment of the electronic device. When both antennas are unblocked, both baseband processors and both antennas may be used in transmitting signals. When one antenna is not available, the device may be operated in a mode in which the available antenna is used and both baseband processors are used or in a mode in which the available antenna is used and only one of the baseband processors is used. Operating mode decisions may be made so as to minimize the potential for intermodulation distortion and absorbed radiation.
    Type: Application
    Filed: January 9, 2012
    Publication date: July 19, 2012
    Inventors: Syed A. MUJTABA, Weiping DOU