Patents by Inventor Xiaoxin Qiu

Xiaoxin Qiu 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: 20090103598
    Abstract: The present invention implements a method and system for dynamically adapting the modulation and coding scheme for radio links in a wireless communications network based on a retransmission environment model in order to maximize throughput and most efficiently allocate bandwidth resources. The present invention encompasses a refined calculus and methodology for deriving the link adaptation thresholds in a retransmission environment using a complex model and analysis of the retransmission environment. The present invention holds particular application for wireless data communications as opposed to real time data services because it is based on a retransmission model applicable primarily for data services. A critical component of this new link adaptation system is a “no transmission” cutoff mode that is selected for SIR below a base threshold value. This new mode prevents system instability and misallocation of bandwidth in a wireless communication system.
    Type: Application
    Filed: December 9, 2008
    Publication date: April 23, 2009
    Inventors: Justin Che-I Chuang, Xiaoxin Qiu
  • Patent number: 7515918
    Abstract: An on-demand message system includes a profile proxy server and a plurality of message servers coupled to a wireless network for sending messages to mobile users under conditions specified by the users and sellers. Users provide profile information specifying categories and conditions for which they will receive messages. Sellers also provide profile information specifying conditions under which they want messages to be sent. A multicast message is sent and processed by target users in response to a predetermined event, e.g., location update, conveying information related to a seller for which the target users have expressed an interest in receiving.
    Type: Grant
    Filed: February 15, 2006
    Date of Patent: April 7, 2009
    Assignee: AT&T Corp.
    Inventors: Li Fung Chang, Hui Luo, Xiaoxin Qiu
  • Publication number: 20090070641
    Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.
    Type: Application
    Filed: October 7, 2008
    Publication date: March 12, 2009
    Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
  • Publication number: 20090036117
    Abstract: A method to adapt channel quality indicator (CQI) reports from user equipment (UE) is provided. This involves first determining the presence of a high-speed shared control channel (HS-SCCH) signal. An estimated signal to noise ratio (SNR) is also determined. Next an SNR correction based on the presence or lack thereof of the HS-SCCH signal and the CRC checks for HS-SCCH and HS-DSCH signals are determined and applied to the estimated SNR. The CQI report is then generated based on the corrected estimated SNR. This CQI report which takes into account a corrected estimated SNR may then be used to adjust the HS-SCCH signal in an HSDPA telephony system.
    Type: Application
    Filed: November 5, 2007
    Publication date: February 5, 2009
    Applicant: BROADCOM CORPORATION
    Inventors: Nelson R. Sollenberger, Li Fung Chang, Xiaoxin Qiu, Hongwei Kong, Severine Catreux
  • Patent number: 7463677
    Abstract: The present invention implements a method and system for dynamically adapting the modulation and coding scheme for radio links in a wireless communications network based on a retransmission environment model in order to maximize throughput and most efficiently allocate bandwidth resources. The present invention encompasses a refined calculus and methodology for deriving the link adaptation thresholds in a retransmission environment using a complex model and analysis of the retransmission environment. The present invention holds particular application for wireless data communications as opposed to real time data services because it is based on a retransmission model applicable primarily for data services. A critical component of this new link adaptation system is a “no transmission” cutoff mode that is selected for SIR below a base threshold value. This new mode prevents system instability and misallocation of bandwidth in a wireless communication system.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: December 9, 2008
    Assignee: AT&T Corp.
    Inventors: Justin Che-I Chuang, Xiaoxin Qiu
  • Patent number: 7457259
    Abstract: This invention provides interference predictions, suitable for least interference dynamic channel assignment use or other frequency hopping uses by de-coupling the time slot assignment and the frequency hopping pattern assignment. In particular, a least interfered time slot is selected based on an aggregate interference measurement performed across an entire transmission band or a pre-specified range of frequencies in the transmission band. A user is assigned a least interfered time slot and provided an appropriate frequency hopping pattern.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: November 25, 2008
    Assignee: AT&T Corp
    Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Bruce Edwin McNair, Xiaoxin Qiu
  • Patent number: 7454512
    Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: November 18, 2008
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
  • Publication number: 20080267100
    Abstract: A wireless device includes a case, user interface, an antenna, first processing resources, and second processing resources. The first processing resources couple to the antenna and to the second processing resources and receive and operate upon a data signal transmitted by a transmitting wireless device. In its processing operations, the first processing resources produces decoded data blocks and writes the decoded data blocks to a data buffer. When a processing resource threshold is met with regard to the plurality of decoded data blocks, the first processing resources issue a service processing interrupt to the second processing resources. In response to the service processing interrupt, the second processing resources retrieve the plurality of decoded data blocks from the data buffer in response to the service processing interrupt and process the plurality of decoded data blocks.
    Type: Application
    Filed: April 27, 2007
    Publication date: October 30, 2008
    Applicant: Broadcom Corporation, a California Corporation
    Inventors: Nelson R. Sollenberger, Srirang Ashok Lovlekar, Hui Luo, Hendrik Frederick Bruyns, Khoi Ly, Xiaoxin Qiu
  • Patent number: 7352720
    Abstract: RF communications received by a wireless terminal from a servicing base station are used to determine the BEP. These RF communications may be in the form of RF bursts that are part of a data frame. The signal to noise ratio (SNR) of the RF burst is determined and a sequence of soft decisions from the RF burst are extracted. The SNR maps to an estimated BEP based upon the modulation format and coding scheme of the RF burst. The soft decisions decode to produce a data block. When the soft decisions decoded favorably, the re-encoded data block produces a sequence of re-encoded decisions. Comparing the re-encoded decisions to the soft decisions yields a re-encoded bit error (RBER). When the decoding is unsuccessful, the BEP is estimated only upon the estimated BEP derived from the SNR. Otherwise, both the estimated BEP and RBER may be used to determine the BEP.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: April 1, 2008
    Assignee: Broadcom Corporation
    Inventors: Li Fung Chang, Yongqian Wang, Huaiyu Zeng, Xiaoxin Qiu, Baoguo Yang
  • Publication number: 20070280158
    Abstract: A baseband processing module of a wireless terminal includes a Turbo decoding module. The Turbo decoding module decodes a Turbo code word to produce one or more Media Access Control (MAC) packet(s) carried by the turbo decode word. Each MAC packet includes a MAC packet header and the MAC packet payload, which carries one or more Radio Link Control (RLC) Packet Data Units (PDUs). The Turbo decoding module decodes the MAC packet header to determine boundaries of the PDUs carried in the MAC packet payload. The Turbo decoding module decodes RLC PDU headers and RLC PDU payloads of the RLC PDUs. The Turbo decoding module writes the decoded MAC packet header, the decoded RLC PDU headers, and the decoded RLC PDU payloads to memory in a word-aligned format. The Turbo decoding module may also operate in various other Turbo decoding modes.
    Type: Application
    Filed: July 19, 2007
    Publication date: December 6, 2007
    Applicant: BROADCOM CORPORATION
    Inventors: Xiaoxin Qiu, Li Fung Chang, Hui Luo, Srirang Lovlekar
  • Patent number: 7280514
    Abstract: A wireless network includes transmission power and data rate adaptation based upon signal quality experienced by the user.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: October 9, 2007
    Assignee: AT&T Corp.
    Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
  • Publication number: 20070189259
    Abstract: Certain aspects of a method and system for a fast cell search using a primary synchronization channel (PSYNC) process in a multimode wideband code division multiple access (WCDMA) terminal are provided. A WCDMA frequency search or a global system for mobile communications (GSM) frequency search is performed based on a current radio access technology (RAT), received signal strength indication (RSSI) scan measurements, and PSYNC detection operations. The RSSI scan measurements may be averaged by making multiple measurements during a measurement period. At least part of the PSYNC detection operations may be performed during a remaining portion of the measurement period. WCDMA carrier frequencies may be marked in accordance with the results of the PSYNC detection operations. For GSM, some of the frequencies may be removed from the search based on the PSYNC marking while the remaining search frequencies may be ranked based on results from the RSSI scan measurements.
    Type: Application
    Filed: February 14, 2006
    Publication date: August 16, 2007
    Inventors: Nelson Sollenberger, Xiaoxin Qiu, Wei Luo
  • Publication number: 20070155334
    Abstract: RF communications received by a wireless terminal from a servicing base station are used to determine the channel quality such as reported bit error probability (BEP). The RF communications may be in the form of RF bursts that are part of a data frame. An estimated BEP may be determined from the signal to noise ratio (SNR) of the RF bursts and or a sequence of soft decisions extracted from the RF bursts, and their historical performance. The SNR maps to an estimated BEP based upon the modulation format of the RF bursts. The soft decisions decode to produce a data block. When the soft decisions decoded favorably, the re-encoded data block produces a sequence of re-encoded decisions. Comparing the re-encoded decisions to the soft decisions yields a re-encoded bit error (RBER). The reported BEP may be based upon the estimated BEP, RBER, and/or RBER threshold. The RBER threshold may be adaptively incremented or decremented depending upon whether or not the RF communications were properly decoded.
    Type: Application
    Filed: March 7, 2007
    Publication date: July 5, 2007
    Applicant: Broadcom Corporation, a California Corporation
    Inventors: Li Chang, Yongqian Wang, Xiaoxin Qiu, Nelson Sollenberger
  • Patent number: 7203461
    Abstract: RF communications received by a wireless terminal from a servicing base station are used to determine the channel quality such as reported bit error probability (BEP). The RF communications may be in the form of RF bursts that are part of a data frame. An estimated BEP may be determined from the signal to noise ratio (SNR) of the RF bursts and or a sequence of soft decisions extracted from the RF bursts, and their historical performance. The SNR maps to an estimated BEP based upon the modulation format of the RF bursts. The soft decisions decode to produce a data block. When the soft decisions decoded favorably, the re-encoded data block produces a sequence of re-encoded decisions. Comparing the re-encoded decisions to the soft decisions yields a re-encoded bit error (RBER). The reported BEP may be based upon the estimated BEP, RBER, and/or RBER threshold. The RBER threshold may be adaptively incremented or decremented depending upon whether or not the RF communications were properly decoded.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: April 10, 2007
    Assignee: Broadcom Corporation
    Inventors: Li Fung Chang, Yongqian Wang, Xiaoxin Qiu, Nelson R. Sollenberger
  • Publication number: 20060264180
    Abstract: RF communications received by a wireless terminal from a servicing base station are used to determine the downlink quality report and implement link adaptation decisions. This involves first implementing an initial transmission scheme between the servicing base station and the wireless terminal. Next, a current downlink quality report corresponding to the initial transmission scheme is generated by the wireless terminal and received at the servicing base station. This downlink quality report is based in whole or in part on a bit-error probability (BEP). The current downlink quality report that corresponds to the initial transmission scheme is then compared to link adaptation thresholds.
    Type: Application
    Filed: July 27, 2006
    Publication date: November 23, 2006
    Applicant: Broadcom Corporation, a California Corporation
    Inventor: Xiaoxin Qiu
  • Patent number: 7126915
    Abstract: The invention provides a traffic regulation technique for media that functions within access protocols by making a percentage of total communication capacity of the media unavailable to end-users as reserve capacity. This reserve capacity is released when appropriate to regulate network traffic. Thus, the traffic regulation technique regulates the traffic by adjusting the percentage of reserve capacity. The reserve capacity may be targeted to a specific type of traffic. In this way, the traffic of the communication system 10 may be regulated so that desired quality of service may be provided for specific end users.
    Type: Grant
    Filed: December 28, 1999
    Date of Patent: October 24, 2006
    Assignee: AT&T Corp.
    Inventors: Xiaolin Lu, Xiaoxin Qiu
  • Patent number: 7124193
    Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: October 17, 2006
    Assignee: AT&T Corp.
    Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
  • Patent number: 7107013
    Abstract: RF communications received by a wireless terminal from a servicing base station are used to determine the downlink quality report and implement link adaptation decisions. This involves first implementing an initial transmission scheme between the servicing base station and the wireless terminal. Next, a current downlink quality report corresponding to the initial transmission scheme is generated by the wireless terminal and received at the servicing base station. This downlink quality report is based in whole or in part on a bit-error probability (BEP). The current downlink quality report that corresponds to the initial transmission scheme is then compared to link adaptation thresholds.
    Type: Grant
    Filed: April 20, 2004
    Date of Patent: September 12, 2006
    Assignee: Broadcom Corporation
    Inventor: Xiaoxin Qiu
  • Publication number: 20060168301
    Abstract: An on-demand message system includes a profile proxy server and a plurality of message servers coupled to a wireless network for sending messages to mobile users under conditions specified by the users and sellers. Users provide profile information specifying categories and conditions for which they will receive messages. Sellers also provide profile information specifying conditions under which they want messages to be sent. A multicast message is sent and processed by target users in response to a predetermined event, e.g., location update, conveying information related to a seller for which the target users have expressed an interest in receiving.
    Type: Application
    Filed: February 15, 2006
    Publication date: July 27, 2006
    Inventors: Li Fung Chang, Hui Luo, Xiaoxin Qiu
  • Patent number: 7079547
    Abstract: The invention provides a method and apparatus for end-users to allocate a communication medium locally without requiring a central arbitration device while guaranteeing access to the end-users. The end-users bid for control of an upstream data channel by concurrently transmitting auction data and address data on a first upstream signaling channel and a second upstream signaling channel. An end-user gains control of the upstream data channel when data received from the first and second downstream signaling channels match the auction and address bits. When it is determined that the end-user lost the bid, the end-user backs off from the first and second upstream signaling channels and refrains from bidding until the first and second upstream signaling channels become quiet.
    Type: Grant
    Filed: May 20, 2002
    Date of Patent: July 18, 2006
    Assignee: AT&T Corp.
    Inventors: Xiaolin Lu, Xiaoxin Qiu