Patents by Inventor Shiau-He Tsai

Shiau-He Tsai 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: 20050245278
    Abstract: A method of allocating forward link transmit power with respect to a mobile station that actively is associated with a serving sector and one or more non-serving sectors of a wireless communication network comprises receiving channel quality information at the non-serving sectors as reported by the mobile station for the serving sector, and allocating forward link transmit power for the mobile station at the non-serving sectors as a function of the reported channel quality information. Non-serving sectors may assume that the reported channel quality information establishes the lower power allocation bound for the mobile station on the assumption that each of them has less favorable radio conditions than the serving sector with respect to the mobile station. Thus, base station transceivers operating as non-serving transmitters with respect to a given mobile terminal may nonetheless determine forward link transmit power allocations for the mobile station using serving sector channel quality information.
    Type: Application
    Filed: April 29, 2004
    Publication date: November 3, 2005
    Inventors: Rath Vannithamby, Shiau-He Tsai, Young Yoon, Anthony Soong
  • Publication number: 20050201296
    Abstract: A communication station employs discontinuous transmission of channel quality feedback to reduce channel quality feedback transmitted over overhead channels. Prior to transmitting channel quality information to a remote station, the communication station compares the channel quality feedback to predetermined qualification criteria. If the qualification criteria are not met, the channel quality feedback is not transmitted. The method may be implemented by a mobile station to reduce channel quality feedback sent to a base station over a reverse link overhead channel.
    Type: Application
    Filed: March 14, 2005
    Publication date: September 15, 2005
    Inventors: Rath Vannithamby, Shiau-He Tsai, Wanshi Chen
  • Publication number: 20050164646
    Abstract: Outer loop power control (OLPC) for the reverse link considers frame information associated with at least two reverse link traffic channels, the transmit power of which is referenced to the transmit power of a reverse link pilot channel R-PICH. A traffic OLPC setpoint is determined based on information such as target frame error rate (FER) and actual frame errors associated with each traffic channel, and the traffic OLPC setpoint is converted to a R-PICH OLPC setpoint. The traffic OLPC setpoint may be calculated from weighted frame information generated by combining the received frame information. Alternatively, a traffic channel OLPC setpoint may be determined for each channel, and a weighted traffic OLPC setpoint calculated from the individual traffic channel OLPC setpoint. The setpoint adjustment may depend on received frame errors, where the power up step size is a multiple of the power down step size, the multiple calculated from target FERs.
    Type: Application
    Filed: December 23, 2004
    Publication date: July 28, 2005
    Inventors: Wanshi Chen, Alpaslan Savas, Shiau-He Tsai, Tao Wu
  • Publication number: 20050036458
    Abstract: A radio base station performs reverse link rate control in a wireless communication network by “stealing” bits on a forward common power control channel. The forward common power control channel is divided into a plurality of frames, with each frame including a plurality of power control groups and each power control group including a plurality of power control slots. The radio base station may dynamically select power control slots depending on user demand to be used for reverse link rate control.
    Type: Application
    Filed: March 15, 2004
    Publication date: February 17, 2005
    Inventors: Young Yoon, Srinivasan Balasubramanian, David Comstock, Long Duan, Ralph Gholmieh, Thawatt Gopal, Patrick Hosein, Anthony Soong, Shiau-He Tsai, Rath Vannithamby, Jonas Wiorek
  • Publication number: 20050037796
    Abstract: A method and apparatus to provide a deterministic power control mechanism for the transmission of mobile station power control commands based on transmitting non-power control commands for which mobile stations exhibit deterministic, observable responses at related transmit powers, e.g., at the same power. For example, a wireless network base station may adjust the target used for sending power control commands to a given mobile station by observing whether that mobile station correctly responds to rate control or retransmit control commands sent at the same transmit power. The mobile station's response (or non-response) to such non-power control commands is readily observable and can be taken as an indication of whether the power target is sufficient for current radio conditions. Although not so limited, this approach may be particularly beneficial where non-power control commands are sent along with the power commands on a sub-channel of a common power control channel.
    Type: Application
    Filed: January 30, 2004
    Publication date: February 17, 2005
    Inventors: Shiau-He Tsai, Anthony Soong, Young Yoon
  • Publication number: 20050032522
    Abstract: A wireless communication network receives packet data transmissions from a mobile station, tracks the occurrence of retransmission requests sent to the mobile station responsive thereto, and modifies the radio link assignments for the mobile station based at least in part on said tracking. For example, a base station controller may be configured to manage the active set of a mobile station based on the number and/or frequency of NACK messages sent by the radio base stations in the mobile station's active set(s) responsive to packet data transmissions from the mobile station. The ACK/NACK response of a radio base station to mobile station transmissions may be used to detect link imbalance, identify poor reverse link channels, etc. The base station controller can add or change radio links based on the ACK/NACK response to improve reverse link performance, trigger voice call handoff, correct link imbalance, etc.
    Type: Application
    Filed: July 12, 2004
    Publication date: February 10, 2005
    Inventors: Anthony Soong, Tao Wu, Thawatt Gopal, Young Yoon, Shiau-He Tsai
  • Publication number: 20050013283
    Abstract: Noise is measured at one or more base stations in a mobile communication system during periodic silence periods. A periodic silence period is defined for at least one carrier that is independent of reverse link channel frame boundaries. The radio base stations transmits silence parameters defining the periodic silence period to mobile stations, which stop transmitting during the periodic silence periods. A time reference is provided to the mobile stations to synchronize the silence periods for all mobile stations.
    Type: Application
    Filed: February 27, 2004
    Publication date: January 20, 2005
    Inventors: Young Yoon, Wanshi Chen, Hsien Woo, Anthony Soong, Srinivasan Balasubramanian, Thawatt Gopal, Long Duan, Shiau-He Tsai
  • Publication number: 20050009551
    Abstract: A communication transceiver transmits a power-controlled first signal responsive to received power control commands and transmits one or more additional signals at variable power gains relative to the transmit power of the first signal based on reception quality feedback received for the additional signals. Thus, a mobile station may transmit a traffic channel at a variable power gain relative to its pilot signal power and vary that gain responsive to reception quality feedback received by it for the traffic signal. Of course, the mobile station may float more than one traffic channel using variable gains and may use different variable gains for each one. Further, the mobile station may float one or more non-pilot channels relative to the pilot or relative to another channel, while transmitting one or more fixed gain channels. Similar variable power gain may be employed at network base stations for forward link signals.
    Type: Application
    Filed: February 27, 2004
    Publication date: January 13, 2005
    Inventors: Shiau-He Tsai, Young Yoon, Tao Wu, Anthony Soong
  • Publication number: 20040017792
    Abstract: Mobile terminals in a high data rate CDMA system may be placed in a control hold mode wherein reverse link control channels are gated, or transmitted at a reduced duty cycle. Mode decisions are based on the activity of the mobile terminal in both the forward and reverse links. A forward link inactivity timer is maintained at the base station that schedules forward link communications to a mobile terminal. The reverse link inactivity timer may be maintained at the same base station, at a different base station in the mobile terminal's active set, or at the base station controller. The forward link inactivity timer may follow the mobile terminal's selection of best forward link serving base station in handoff. When both the forward and reverse link inactivity timers have expired, and no forward link data is pending, the mobile terminal may be commanded to a control hold mode.
    Type: Application
    Filed: July 24, 2002
    Publication date: January 29, 2004
    Inventors: Farideh Khaleghi, Patrik Nils Lundqvist, Shiau-He Tsai
  • Publication number: 20030040315
    Abstract: A wireless communication network reduces its signaling overhead by recognizing when a mobile station transitions from an inactive state, such as Control Hold or quasi-active, back to an active state. Based on such recognition by the network, the mobile station begins sending desired traffic data without need for explicitly negotiating its return to active state, thereby reducing or eliminating higher-layer signaling, e.g., Layer 3 and above, that is otherwise required for return to active state operations. The network might further avoid explicit signaling by, for example, using transmitted reverse link Power Control Bits to indicate that an inactive mobile station should remain inactive. In this manner, inactive mobile stations may be allowed to return to active state without explicit signaling where appropriate, or held in the inactive state if needed, all without need for explicit network signaling.
    Type: Application
    Filed: July 31, 2002
    Publication date: February 27, 2003
    Inventors: Farideh Khaleghi, Anthony C.K. Soong, Jonas Wiorek, Patrik Nils Lundgvist, Shawn Shiau-He Tsai, Young C. Yoon