Patents by Inventor Qian Zhang

Qian Zhang 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: 6999432
    Abstract: A cross-layer architecture is provided for delivering multiple media streams over 3G W-CDMA channels in adaptive multimedia wireless networks. A resource management mechanism dynamically allocates resources among different media streams adapted to channel status and Quality of Service (QoS) requirements. By taking the time-varying wireless transmission characteristics into account, an allocation of resources is performed based on a minimum-distortion or minimum-power criterion. Estimates of the time-varying wireless transmission conditions are made through measurements of throughput and error rate. Power and distortion minimized bit allocation schemes are used with the estimated wireless transmission conditions to for dynamically adaptations in transmissions.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: February 14, 2006
    Assignee: Microsoft Corporation
    Inventors: Qian Zhang, Wenwu Zhu, Ya-Qin Zhang, Guijin Wang
  • Patent number: 6982949
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: January 3, 2006
    Assignee: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050286523
    Abstract: An implementation of a technology, described herein, for transmitting compressed network transport-layer-protocol headers in a speedy, efficient, inferentially synchronized, and robust manner. An implementation, described herein, models the transmission of compressed headers to the congestion procedure of the network transport-layer protocol (e.g., TCP's). Doing so, the sender of the compressed headers can infer whether the receiver correctly received them. Unlike the slow direct synchronization employed by conventional schemes, this implementation of the present claimed invention inferentially synchronizes by modeling after the congestion procedure of the network transport-layer protocol. This is inherently faster than direct synchronization. Since the implementation performs well over both noiseless and noisy links, it is particularly suited to use over wireless communications channels. This abstract itself is not intended to limit the scope of this patent.
    Type: Application
    Filed: August 15, 2005
    Publication date: December 29, 2005
    Applicant: Microsoft Corporation
    Inventors: HongBin Liao, Qian Zhang, Wenwu Zhu, Ya-Qin Zhang
  • Publication number: 20050250508
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Application
    Filed: June 27, 2005
    Publication date: November 10, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050251577
    Abstract: An end host in a peer-to-peer system stores identifiers for both its peers and the neighbors of its peers. When the IP address of the end host and one of the peers changes, the end host's new IP address can be sent to each neighbor of the peer so that communication between the end host and the peer will not be lost. The order in which the neighbors of the peer are stored can be prioritized for faster delivery of the end host's changed IP address to the peer. The prioritizing can be by available bandwidth of the neighbors, proximity of the neighbors, trust between the peer and its neighbors, the probability that the IP address of the neighbors will change, etc. Proximity of the peers from each other and the end host can be a function of the identifier, which can be generated from a public key.
    Type: Application
    Filed: April 20, 2004
    Publication date: November 10, 2005
    Inventors: Chuanxiong Guo, Haitao Wu, Kun Tan, Qian Zhang, Wenwu Zhu
  • Publication number: 20050213542
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Application
    Filed: June 7, 2005
    Publication date: September 29, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050201279
    Abstract: A spurious timeout (STO) response allows a sending device to conservatively adjust congestion state parameters and maintain the packet flow, after detection of the STO. Since occurrence of an STO may be accompanied by data loss, the STO response couples the spurious timeout and the loss event by maintaining a value of previously available bandwidth and increasing a limit that a sending host can send based on a pattern of returned acknowledgements. In particular, the limit is increased by the maximum size of a data segment that the sending host can send each time an acknowledgement is received from the receiving host indicating a successful transmission of a data packet. Thus, a positive data flow may be maintained conservatively while avoiding further packet losses and an unnecessary re-transmission of data packets that may have been successfully received by the receiving host.
    Type: Application
    Filed: March 15, 2004
    Publication date: September 15, 2005
    Inventors: Kun Tan, Qian Zhang, Wenwu Zhu
  • Patent number: 6944144
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: September 13, 2005
    Assignee: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050198350
    Abstract: A method for detecting a spurious timeout in a TCP network which can be used to avoid unnecessarily triggering the TCP rate adaptation is disclosed. Upon detection of a timeout on a given packet, a shortened packet version of the possibly lost packet is retransmitted. The retransmitted packet is at least one byte shorter than the original packet. The node receiving this retransmitted packet will acknowledge the receipt of the packet as specified in the TCP protocol. The acknowledgment will contain the sequence number of the lowest byte the receiving node has not yet received. Because the retransmitted packet is shorter than the original packet, the sequence number of this as yet not received byte will be less than or equal to the last byte of the original packet if the original packet was not received indicating a valid timeout.
    Type: Application
    Filed: January 15, 2004
    Publication date: September 8, 2005
    Applicant: Microsoft Corporation
    Inventors: Kun Tan, Hongbin Liao, Chuanxiong Guo, Qian Zhang, Wenwu Zhu
  • Patent number: 6937591
    Abstract: A method provides differentiated quality of service (QoS) by providing adaptive updates to media access control (MAC) layer parameters on a distributed basis. The method includes calculating a failure probability for a transmission over the network, determining a target value for determining a contention window according to a mapped function of the failure probability, and altering the contention window according to a scaling function of the target value. The mapped function and the scaling can provide QoS differentiation. A wireless device ensures fairness in a wireless time slotted network and includes a network interface card (NIC), a network driver interface, a network monitor, a statistics engine, and an adaptive parameter engine for determining a target value for determining a contention window according to a mapped function of the one or more probabilities to enable an alteration of the contention window and provide new parameters for the MAC layer.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: August 30, 2005
    Assignee: Microsoft Corporation
    Inventors: Zihua Guo, Wenwu Zhu, Qian Zhang, Jun Zhao
  • Publication number: 20050163098
    Abstract: An implementation of a technology, described herein, for transmitting compressed network transport-layer-protocol headers in a speedy, efficient, inferentially synchronized, and robust manner. An implementation, described herein, models the transmission of compressed headers to the congestion procedure of the network transport-layer protocol (e.g., TCP's). Doing so, the sender of the compressed headers can infer whether the receiver correctly received them. Unlike the slow direct synchronization employed by conventional schemes, this implementation of the present claimed invention inferentially synchronizes by modeling after the congestion procedure of the network transport-layer protocol. This is inherently faster than direct synchronization. Since the implementation performs well over both noiseless and noisy links, it is particularly suited to use over wireless communications channels. This abstract itself is not intended to limit the scope of this patent.
    Type: Application
    Filed: March 17, 2005
    Publication date: July 28, 2005
    Applicant: Microsoft Corporation
    Inventors: HongBin Liao, Qian Zhang, Wenwu Zhu, Ya-Qin Zhang
  • Publication number: 20050155080
    Abstract: A resource allocation of multiple compressed AV streams delivered over the Internet is disclosed that achieves end-to-end optimal quality through a multimedia streaming TCP-friendly transport (MSTFP) protocol that adaptively estimates the network bandwidth while smoothing the sending rate. Resources allocated dynamically according to a media encoding distortion and network degradation algorithm. A scheme is also disclosed for dynamically estimating the available network bandwidth for streaming of objects, such as MPEG4 multiple video objects, in conjunction with the MSTFP protocol. The scheme can account for packet-loss rates to minimize end-to-end distortion for media delivery.
    Type: Application
    Filed: January 27, 2005
    Publication date: July 14, 2005
    Applicant: Microsoft Corporation
    Inventors: Qian Zhang, Ya-Qin Zhang, Wenwu Zhu
  • Publication number: 20050128944
    Abstract: A framework and method for quality of service (QoS) aware resource discovery in mobile ad hoc networks are presented. Self-organized discovery agents manage the directory information that describes the network resources available for use by clients. In one embodiment, hash indexing of available resources is utilized. The discovery agents also partition the network into domains and collect intra- and inter-domain QoS information. This information is used to allow clients to select appropriate resource providers. This framework and method has low discovery latency and cost in terms of the number of packets for each resource discovery query.
    Type: Application
    Filed: January 27, 2005
    Publication date: June 16, 2005
    Applicant: Microsoft Corporation
    Inventors: Qian Zhang, Wenwu Zhu, Jiangchuan Liu
  • Publication number: 20050122902
    Abstract: A method provides differentiated quality of service (QoS) by providing adaptive updates to media access control (MAC) layer parameters on a distributed basis. The method includes calculating a failure probability for a transmission over the network, determining a target value for determining a contention window according to a mapped function of the failure probability, and altering the contention window according to a scaling function of the target value. The mapped function and the scaling can provide QoS differentiation. A wireless device ensures fairness in a wireless time slotted network and includes a network interface card (NIC), a network driver interface, a network monitor, a statistics engine, and an adaptive parameter engine for determining a target value for determining a contention window according to a mapped function of the one or more probabilities to enable an alteration of the contention window and provide new parameters for the MAC layer.
    Type: Application
    Filed: January 12, 2005
    Publication date: June 9, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Wenwu Zhu, Qian Zhang, Jun Zhao
  • Publication number: 20050100040
    Abstract: A method provides differentiated quality of service (QoS) by providing adaptive updates to media access control (MAC) layer parameters on a distributed basis. The method includes calculating a failure probability for a transmission over the network, determining a target value for determining a contention window according to a mapped function of the failure probability, and altering the contention window according to a scaling function of the target value. The mapped function and the scaling can provide QoS differentiation. A wireless device ensures fairness in a wireless time slotted network and includes a network interface card (NIC), a network driver interface, a network monitor, a statistics engine, and an adaptive parameter engine for determining a target value for determining a contention window according to a mapped function of the one or more probabilities to enable an alteration of the contention window and provide new parameters for the MAC layer.
    Type: Application
    Filed: October 21, 2004
    Publication date: May 12, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Wenwu Zhu, Qian Zhang, Jun Zhao
  • Publication number: 20050083874
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Application
    Filed: October 18, 2004
    Publication date: April 21, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050068913
    Abstract: A system is presented for providing a middleware communication space that provides asynchronous message delivery service for partially connected mobile ad hoc networks. Embodiments of the present invention use mobile devices to bridge separated islands of networks and store and propagate messages. The system and software architecture supports methods for messaging caching, transferring and routing. More specifically, embodiments provide methods and systems that extend a communication space concept into a distributed environment and combine it with the standard Web Services technologies, i.e, SOAP, and WS series protocols. The communication space provides an extension of Web Services to mobile ad hoc networks and provides asynchronous message caching, transferring and routing.
    Type: Application
    Filed: September 17, 2003
    Publication date: March 31, 2005
    Applicant: Microsoft Corporation
    Inventors: Kun Tan, Qian Zhang, Wenwu Zhu
  • Publication number: 20050068982
    Abstract: A system and method for improved vertical handoff between different types of wireless network. Network allocation vector occupation and packet collision probability are used as quality of service measures, enabling vertical handoffs to be delayed until actually beneficial to quality of service. Improved wireless network cell boundary detection in vertical handoff scenarios is achieved with a Fourier-based technique in conjunction with an adaptively determined minimum operating signal strength threshold. Improved wireless network cell boundary detection enables vertical handoffs from high quality of service networks to be delayed as long as possible. Together, practical wireless network quality of service measures and improved detection of wireless network cell boundaries in vertical handoff scenarios reduce the rate of unnecessary vertical handoff resulting in higher overall quality of service experienced by a mobile computing device roaming between wireless network types.
    Type: Application
    Filed: October 18, 2004
    Publication date: March 31, 2005
    Applicant: Microsoft Corporation
    Inventors: Zihua Guo, Qian Zhang, Richard Yao, Wenwu Zhu
  • Publication number: 20050060406
    Abstract: Overlay network peers may be grouped so that each peer in a peer group has a similar transport network proximity measure with respect to the peers in other peer groups. A first set of transport network distances may include distances between a peer group and peer group neighbors of the peer group. A second set of distances may include distances between a peer and the peer group neighbors of the peer group. The peer may decide to join the peer group if the first set of distances is near to the second set. A first peer group may query a second peer group for the second peer group's neighboring peer groups. The distance between the first peer group and each of the second peer group's neighbors may be measured. Overlay network connections may be established between the first peer group and the closest of the second peer group's neighbors.
    Type: Application
    Filed: September 15, 2003
    Publication date: March 17, 2005
    Applicant: Microsoft Corporation
    Inventors: Xin Zhang, Qian Zhang, Yongqiang Xiong, Wenwu Zhu
  • Publication number: 20050031643
    Abstract: Therapeutic methods and microorganisms therefore are provided. The microorganisms are designed to accumulate in immunoprivileged tissues and cells, such as in tumors and other proliferating tissue and in inflamed tissues, compared to other tissues, cells and organs, so that they exhibit relatively low toxicity to host organisms. The microorganisms also are designed or modified to result in leaky cell membranes of cells in which they accumulate, resulting in production of antibodies reactive against proteins and other cellular products and also permitting exploitation of proliferating tissues, particularly tumors, to produce selected proteins and other products. Methods for making tumor specific antibodies and also methods of making gene products encoded by the microorganism as well as antibodies reactive therewith are provided.
    Type: Application
    Filed: June 18, 2004
    Publication date: February 10, 2005
    Inventors: Aladar Szalay, Tatyana Timiryasova, Yong Yu, Qian Zhang