Patents by Inventor Reza Shahidi

Reza Shahidi 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: 7587203
    Abstract: Admission control is performed on a forward link shared packet data channel based on the measured delay per unit of data transmitted on the channel or the data throughput on the channel. In another embodiment, statistical analyses of channel quality metrics received at a base station are compared to the data rate used to serve mobile stations on the packet data channel to perform admission control. In any case, admission control may be performed for a new call setup request, hard handoff or virtual handoff. Admission control may be performed independently for a plurality of Quality of Service (QoS) flow categories, such as real time, best effort, rate sensitive, or QoS categories defined by cost. Users may be allocated among QoS flow categories as necessary to maintain performance.
    Type: Grant
    Filed: October 20, 2005
    Date of Patent: September 8, 2009
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Reza Shahidi, Wanshi Chen, Rath Vannithamby, Keerthi Govind
  • Patent number: 7573856
    Abstract: A radio base station (RBS) provides dynamic rate adaptation for rate-adjustable communication channels used to transmit information to remote mobile stations based on monitoring transmit power information associated with those channels. For a given channel, the RBS tracks an average channel power on a per transmit frame basis and compares the average to first and second rate adjustment thresholds, which comparisons trigger downward or upward rate adjustments. Similar operation also may be based on averaging the power control commands returned by the mobile station, which indicate whether the channel's power as received by the mobile station is or is not sufficient with respect to a desired signal quality. This method thus provides a mechanism for rapid rate adaptation without requiring explicit rate control signaling from the mobile stations.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: August 11, 2009
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Wanshi Chen, Reza Shahidi, Alpaslan Savas, Long Duan, Joakim Hulten
  • Publication number: 20090005044
    Abstract: The disclosure relates to techniques for maintaining minimum quality of service (QoS) communication sessions with a wireless communication device (WCD) over a data-based communication network during a hard handoff between access networks for the WCD. More specifically, the techniques determine whether a closed connection between the WCD and a first access network during a minimum QoS communication session is due to a hard handoff between the first access network and a second access network. In the case of a hard handoff, the techniques maintain open QoS reservations associated with data flows included in the minimum QoS communication session for a predetermined period of time to enable a new connection to be established between the WCD and a second access network. The techniques described herein may especially useful when performing a voice over Internet Protocol (VoIP) call over an Evolution-Data Optimized (EVDO) communication network.
    Type: Application
    Filed: August 7, 2007
    Publication date: January 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Ajith T. Payyappilly, Lei Shen, Parag Arun Agashe, Reza Shahidi
  • Publication number: 20090003208
    Abstract: Techniques for maintaining an always-on data session for an access terminal are described. Messages to keep alive the data session may be sent using non-traffic channels to avoid bringing up traffic channels just to send these messages. In one design, an access network may send a first message (e.g., a RouteUpdateRequest message) on a first non-traffic channel (e.g., a control channel) to the access terminal. The access terminal may return a second message (e.g., a RouteUpdate message) on a second non-traffic channel (e.g., an access channel) to the access network. The access network may then send a third message (e.g., for an Echo-Request) on the first non-traffic channel over a smaller area covering an approximate location of the access terminal, which may be determined based on the second message. The access terminal may return a fourth message (e.g., for an Echo-Reply) on the second non-traffic channel to the access network.
    Type: Application
    Filed: July 30, 2007
    Publication date: January 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Ajith T. Payyappilly, Lei Shen, Parag Arun Agashe, Reza Shahidi
  • Publication number: 20080305772
    Abstract: Systems and methodologies are described that effectuate establishment of an IPSec tunnel for utilization in a wireless communication environment. IPSec establishment procedures on home base stations can be used to establish IPSec tunnels between home base stations situated on open access sectors of wireless communication environments and packet data interworking function components positioned at the contiguity of secured segments of the wireless communication environments. Moreover, high rate packet data point-to-point protocol challenge-handshake authentication protocols can be directed through the IPSec tunnels to facilitate authentication of access terminals associated with the home base stations in order to facilitate further communications with components dispersed within secure areas of wireless communication environments.
    Type: Application
    Filed: June 3, 2008
    Publication date: December 11, 2008
    Applicant: QUALCOMM Incorporated
    Inventors: Srinivasan Balasubramanian, Raymond Tah-Sheng Hsu, Reza Shahidi
  • Publication number: 20080198871
    Abstract: In general, this disclosure is directed to establishment and release of a connection between a communication device and an access network. More specifically, the techniques of this disclosure are directed to determining when a data flow used for exchanging call control requests becomes inactive. For example, a communication device may dynamically adjust an inactivity timer threshold associated with the data flow used by applications to exchange call control messages when a new call control transaction starts or an existing call control transaction ends, e.g., by selecting a single inactivity timer threshold for the data flow to satisfy minimum connection requirements of existing call control transactions, recently ended call control transactions and the new call control transaction. The data flow is considered inactive when no applications send or receive messages via the data flow for a period of time that exceeds the adjusted inactivity timer threshold.
    Type: Application
    Filed: February 21, 2007
    Publication date: August 21, 2008
    Inventors: Reza Shahidi, Samir Vijay Ginde
  • Publication number: 20080123527
    Abstract: Techniques to detect for end of service using dynamic inactivity timer thresholds are described. An access terminal establishes a radio connection for one or more applications. Data and signaling for the application(s) may be sent on one or more first flows (e.g., RLP flows) that may carry any number of second flows (e.g., IP flows). The access terminal determines a dynamic inactivity timer threshold for each first flow, e.g., based on at least one inactivity timer threshold for at least one second flow mapped to that first flow. The access terminal determines whether each first flow is inactive based on the inactivity timer threshold for that first flow, e.g., declares each first flow to be inactive if no activity is detected on that first flow for a period exceeding the inactivity timer threshold. The access terminal closes the radio connection when all first flow(s) are determined to be inactive.
    Type: Application
    Filed: May 3, 2007
    Publication date: May 29, 2008
    Applicant: QUALCOMM INCORPORATED
    Inventors: Reza Shahidi, Ajith T. Payyappilly, Srinivasan Balasaubramanian, Lei Shen
  • Publication number: 20080117859
    Abstract: An operational mode of a terminal is dynamically configured to allow the terminal to receive services of interest to the terminal while potentially conserving battery power. The terminal operates in a first mode (e.g., an HRPD-only mode) and monitors only a first radio network (e.g., an HRPD network) for pages from a first data network (e.g., and IMS network) if all services from a second data network (e.g., an ANSI-41 network) of interest to the terminal is obtainable via the first radio network. The terminal operates in a second mode (e.g., an 1X-HRDP mode) and monitors the first radio network and a second radio network (e.g., a 1X network) for pages from the first and second data networks, respectively, if at least one service from the second data network of interest to the terminal is not obtainable via the first radio network. The terminal may dynamically select the first or second mode.
    Type: Application
    Filed: November 21, 2006
    Publication date: May 22, 2008
    Inventors: Reza Shahidi, Deepak Khandelwal
  • Patent number: 7376102
    Abstract: A method of reducing loading on backhaul communications links in a wireless communications system suppresses a portion of the upward flow of frame information for idle and/or erased frames in certain situations, such as when multiple ones of such frames are successively encountered. A radio base station abstains from sending a frame header to a BSC/ANC for second and following frames of the Idle type and/or the radio base station abstains from sending a frame header to a BSC/ANC for second and following frames of the Erased type. The header may also or alternatively be suppressed for an Idle frame immediately following a Good frame. The BSC/ANC in effect fills in the suppressed frame information in such situations, forwards appropriate indications of frame type to the frame selection algorithm.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: May 20, 2008
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Reza Shahidi, Vincent B. Baglin
  • Publication number: 20070286117
    Abstract: Techniques to configure quality of service (QoS) for communication are described. An access terminal configures a first QoS profile prior to a call. This QoS profile is for a set of QoS parameters that provides certain QoS. The access terminal thereafter establishes (e.g., originates or terminates) a call with an access network. If the first QoS profile is appropriate for the call, then QoS is not reconfigured. However, the access terminal may determine that a second QoS profile is to be used for the call, e.g., based on a format or a rate set supported by a remote/other terminal for the call. The access terminal would then configure the second QoS profile during the call. The access terminal may exchange data in accordance with (a) the first QoS profile before the second QoS profile is configured and activated and (b) the second QoS profile after it is configured and activated.
    Type: Application
    Filed: March 16, 2007
    Publication date: December 13, 2007
    Inventors: Srinivasan Balasubramanian, Reza Shahidi
  • Publication number: 20070192090
    Abstract: A variable rate vocoder is configured to encode speech signals with a plurality of encoding rates and to change from a first encoding rate to a second encoding rate according to a received signal indicating reverse link load.
    Type: Application
    Filed: February 15, 2006
    Publication date: August 16, 2007
    Inventor: Reza Shahidi
  • Publication number: 20070127413
    Abstract: A method of reducing loading on backhaul communications links in a wireless communications system suppresses a portion of the upward flow of frame information for idle and/or erased frames in certain situations, such as when multiple ones of such frames are successively encountered. A radio base station abstains from sending a frame header to a BSC/ANC for second and following frames of the Idle type and/or the radio base station abstains from sending a frame header to a BSC/ANC for second and following frames of the Erased type. The header may also or alternatively be suppressed for an Idle frame immediately following a Good frame. The BSC/ANC in effect fills in the suppressed frame information in such situations, forwards appropriate indications of frame type to the frame selection algorithm.
    Type: Application
    Filed: December 1, 2005
    Publication date: June 7, 2007
    Inventors: Reza Shahidi, Vincent Baglin
  • Publication number: 20070121553
    Abstract: A reference signal including a quality indication is injected into the reverse link signal received at a base station. The transmit power of the reference signal is controlled by the base station through reverse link power control, and the base station estimates the reverse link load from the transmit power of the reference signal. As the load increases, the transmit power must increase to overcome interference. The reference signal may be generated by a signal generator within the base station; by a mobile station hardwired to the base station; or by a mobile station proximate the base station, sending the reference signal over the air interface. The reverse link load may be estimated directly from reference signal transmit power, or from the reference signal transmit power minus a minimum reference signal transmit power in the absence of interference.
    Type: Application
    Filed: November 28, 2005
    Publication date: May 31, 2007
    Inventors: Young Yoon, Reza Shahidi
  • Publication number: 20070091801
    Abstract: Admission control is performed on a forward link shared packet data channel based on the measured delay per unit of data transmitted on the channel or the data throughput on the channel. In another embodiment, statistical analyses of channel quality metrics received at a base station are compared to the data rate used to serve mobile stations on the packet data channel to perform admission control. In any case, admission control may be performed for a new call setup request, hard handoff or virtual handoff. Admission control may be performed independently for a plurality of Quality of Service (QoS) flow categories, such as real time, best effort, rate sensitive, or QoS categories defined by cost. Users may be allocated among QoS flow categories as necessary to maintain performance.
    Type: Application
    Filed: October 20, 2005
    Publication date: April 26, 2007
    Inventors: Reza Shahidi, Wanshi Chen, Rath Vannithamby, Keerthi Govind
  • Patent number: 7046640
    Abstract: A wireless network planning tool simulates wireless network operation, including subscriber admission processing, based on sophisticated reverse and forward link analyses that include data fall back procedures. Subscribers are associated with an application type, where each application type preferably has maximum and minimum data rates and one or more fall back rates. During simulation, the tool may use fall back when evaluating forward and reverse communication links between subscribers and their associated sectors (base stations). A subscriber unable to close a reverse link to a given sector at a given data rate, may be re-evaluated at a lower rate under fallback procedures. Forward link analysis incorporates similar fallback procedures in forward link call admission. Fallback procedures include appropriate supplemental channel adjustments, and corresponding forward and reverse link power adjustments reflecting adjusted data rates.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: May 16, 2006
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Juan J. Silva, Mauricio Guerra, Reza Shahidi
  • Patent number: 6934555
    Abstract: A wireless network planning tool simulates wireless network operation, including subscriber admission processing based resource reservation procedures. Simulated subscribers are associated with an application type. Application types are broadly categorized as either voice type or data type applications. Subscribers of both types are simultaneously simulated. During subscriber admission processing, the CDMA planner attempts to admit simulated subscribers to individual sectors or base stations. At each sector, a percentage of the total forward power capacity is reserved for voice users, and a second or remaining percentage may be reserved for data users. When admitting a voice user to a sector with insufficient remaining power in its voice bucket, the CDMA planner may borrow from the power bucket reserved for data users. Setting aside a power bucket for voice users at each sector insures that one or a few high data rate users do not consume all available resources in a sector.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: August 23, 2005
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Juan J. Silva, Mauricio Guerra, Reza Shahidi
  • Patent number: 6931257
    Abstract: A wireless communication network includes base stations that operate with variable transmit power adjustments during soft handoff of a mobile station. Base stations adjust current transmit powers up or down using variable step sizes responsive to power control commands from the mobile station. Step size depends on the difference between current transmit power and a common reference power. Generally, power control commands that move transmit power away from the common reference power are attenuated by decreasing the step size, and those that move the transmit power toward the reference power are amplified by increasing step size. A base station controller adjusts the common reference power during soft handoff to reduce differences between it and the current transmit powers. Thus, step size may be large at the outset of soft handoff to quickly reduce transmit power imbalance between base stations, but tends to decrease with subsequent adjustments of the common reference power.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: August 16, 2005
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Reza Shahidi, Nirmal Velayudhan
  • Publication number: 20050113106
    Abstract: A wireless communication network manages variable data rate communication channels using both short-term data rate adaptation and longer-term resource allocation adjustment. For example, an exemplary base station system may track the actual transmit power being used to transmit a given communication channel on a per frame basis, or faster, and use that tracked value to infer changing channel conditions, e.g., for a given current data rate, higher power indicates poorer channel conditions and lower power indicates better channel conditions. Additionally, or alternatively, channel quality information reported by a receiving mobile station can be used. Regardless, relatively fast data rate changes can be made responsive to monitoring the channel conditions, while retaining the communication resource allocation for the channel. Over the longer term, however, the allocation itself can be changed, e.g., increased or decreased, depending on whether the channel is being efficiently utilized.
    Type: Application
    Filed: June 10, 2004
    Publication date: May 26, 2005
    Inventors: Long Duan, Rath Vannithamby, Wanshi Chen, Reza Shahidi, Alpaslan Savas, Joakim Hulten
  • Publication number: 20050113104
    Abstract: A radio base station (RBS) provides dynamic rate adaptation for rate-adjustable communication channels used to transmit information to remote mobile stations based on monitoring transmit power information associated with those channels. For a given channel, the RBS tracks an average channel power on a per transmit frame basis and compares the average to first and second rate adjustment thresholds, which comparisons trigger downward or upward rate adjustments. Similar operation also may be based on averaging the power control commands returned by the mobile station, which indicate whether the channel's power as received by the mobile station is or is not sufficient with respect to a desired signal quality. This method thus provides a mechanism for rapid rate adaptation without requiring explicit rate control signaling from the mobile stations.
    Type: Application
    Filed: November 25, 2003
    Publication date: May 26, 2005
    Inventors: Wanshi Chen, Reza Shahidi, Alpaslan Savas, Long Duan, Joakim Hulten
  • Publication number: 20050107091
    Abstract: In a wireless communication network providing voice and data services, one or more entities in the network, such as a base station controller and/or radio base station, can be configured to reduce data services overhead responsive to detecting a congestion condition, thereby increasing the availability of one or more network resources for voice services. In one or more exemplary embodiments, one or more current data services users are targeted for modification of their ongoing data services to effect the reduction in data services overhead. Modifications can include, but are not limited to, any one or more of the following: forward or reverse link data rate reductions, and shifting of forward or reverse link traffic from dedicated user channels to shared user channels. Targeting of users for service modification can be based on reported channel quality information. For example, users reporting poor radio conditions can be targeted first for service modifications.
    Type: Application
    Filed: May 28, 2004
    Publication date: May 19, 2005
    Inventors: Rath Vannithamby, Long Duan, Reza Shahidi, Wanshi Chen, Seema Madan