Patents by Inventor Liwen Chu

Liwen Chu 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: 8553714
    Abstract: A unified contention based protocol is implemented in which a source station within a basic service set selects the protection methodology for data transmission on the communication medium. Utilizing EDCA as a medium access method and maintaining that each transmission opportunity has multiple slots, the source station is provided with the opportunity to select a protection methodology based on the protection environment, which enables transmission opportunity protection without direct PCP involvement.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: October 8, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George Vlantis
  • Publication number: 20130194920
    Abstract: TDLS support in VHT devices is enabled through the use of added VHT fields in the TDLS frames. A VHT TDLS direct link can be setup through a respective TDLS Setup Request/Response with added field announcing VHT Capabilities of the VHT device and the peer device. Added VHT Operation field in the TDLS Setup Confirm frame adds supports between VHT peer devices for non-VHT BSS and VHT BSS. Two VHT STAs can establish wider TDLS channel than BSS operating channel through TDLS establishment. VHT off channel support is enabled by adding Wide Bandwidth Channel Switch field in the TDLS Channel Switch Request frame and no changes to TDLS Channel Switch Response. A VHT Capabilities field is also added to TDLS Discovery Response frame to inform peer devices of device capabilities.
    Type: Application
    Filed: January 27, 2012
    Publication date: August 1, 2013
    Applicant: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8488558
    Abstract: Handover of the role of a personal basic service set coordination point (PCP) in a personal wireless area network occurs with the issuance of a PCP handover request by the existing PCP station. A response from a PCP handover capable station within the BSS includes attributes of the responding station pertinent to its ability to carry out the role of a PCP. Once a new PCP station has been identified, handover steps are undertaken to modify beacon filtering and beam-forming in other non-PCP stations within the BSS to facilitate interruption free transition from the old PCP to the new PCP.
    Type: Grant
    Filed: May 6, 2010
    Date of Patent: July 16, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George Vlantis
  • Publication number: 20130176921
    Abstract: A wireless, specifically VHT, system that includes APs and STAs can power save during the TXOP. The AP in the system announces whether STAs in the system do SU or MU TXOP power save in a Beacon/Probe Response, and the STAs in the system transmit to the AP whether the STA is capable and willing to save power during a SU, MU, or SU+MU TXOP. For the AP, the process further involves buffering data frames for STAs that have entered doze mode until the end of TXOP. The AP further transmits to STAs a duration of TXOP in the Duration field of a RTS frame. The STA can inform the AP to enter TXOP PM mode in a bit in the HT Control field.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 11, 2013
    Applicant: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8483192
    Abstract: A six field address scheme identifies both the originating point and the endpoint of a data frame enabling multiple hop forwarding through a plurality of intermediate mesh points in a wireless mesh network. Data frames originating or ending at a point outside of the wireless mesh network access the wireless network at a mesh access point using a legacy address scheme. The legacy address schemes are converted to a six address scheme using a proxy address table at the access point. Each mesh access point includes not only a routing table but a proxy address table as well as enabling the mesh access point, and/or mesh portal points, to convert address schemes having less than six address fields to the six field format. Subsequent to the conversion, mesh points within the wireless mesh network need only the routing table to facilitate the forwarding of the data frame.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: July 9, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, Kyeongsoo Kim, George Vlantis
  • Patent number: 8437333
    Abstract: Contention based period beamforming includes the establishment of synchronized communications between a beamforming initiator and a beamforming responder to precisely define a start time for beamforming training. Synchronization between the beamforming initiator and beamforming responder begins with the sending of control information to the responder so that the start of the beamforming process will be synchronized. With beamforming training synchronized, beamforming is initiated using the sector sweep process.
    Type: Grant
    Filed: July 6, 2010
    Date of Patent: May 7, 2013
    Assignees: STMicroelectronics, Inc., STMicroelectronics Srl
    Inventors: Liwen Chu, George A. Vlantis, Vincenzo Scarpa
  • Patent number: 8432847
    Abstract: Methods and apparatus for transmitting a video frame in wireless local area network communications are proposed. In one aspect, a method generates and transmits an IEEE 802.11 media access control (MAC) frame containing a video transport stream (VTS) frame. The VTS frame includes a video frame and a VTS control header that includes control information with respect to the video frame.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: April 30, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8391259
    Abstract: A protocol for collision avoidance in inter and intra basic service set broadcast/multicast communication in a wireless network is disclosed. An access point reserves a broadcast transmission time and conveys that reservation to each of its associated stations. Using a beacon or an action frame, the transmission reservation time is sent to all stations and other neighboring access points within range of the primary access point. Upon receiving the broadcast transmission time reservation, each station associated with the reserving access point and any neighboring access points set their network allocation vector thus preventing frame transmission or reception during the now reserved transmission time.
    Type: Grant
    Filed: February 24, 2009
    Date of Patent: March 5, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8374080
    Abstract: The addition of high throughput capability elements to beacon frames and peer link action frames in wireless mesh networks enable the utilization of desirable features without further modifications to the network. Rules can be established for high throughput mesh point protection in a mesh network, Space-time Block Code (STBC) operations and 20/40 MHz operation selections. However, features such as PSMP (power save multi-poll) and PCO (phased coexistence operations) are barred from implementation to prevent collisions.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: February 12, 2013
    Assignees: STMicroelectronics, Inc., STMicroelectronics Srl
    Inventors: Liwen Chu, George Vlantis, Vincenzo Scarpa
  • Patent number: 8369257
    Abstract: A reliable and deterministic video communication protocol is provided. In one aspect, a method of transmitting data, audio or video frames in a basic service set having a plurality of stations in a wireless local area network transmits a transmit opportunity information element to reserve a transmit opportunity time interval. The method further transmits the data, audio or video frames to a number of the stations in the basic service set during the reserved transmit opportunity time interval. In another aspect, a method of transmitting data, audio or video frames in a basic service set having a plurality of stations in a wireless local area network first transmits protection frames to reserve a time interval, then transmits frames during the reserved time interval or during a non-reserved time interval.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: February 5, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8364187
    Abstract: A subframe structure for wireless communication uses a master common subframe and second master common subframe method to give BSs different priorities to serve overlapping areas in common subframes. The subframe structure and corresponding method can increase overlapping cells' capacity and reduce interference.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: January 29, 2013
    Assignee: STMicroelectronics, Inc.
    Inventor: Liwen Chu
  • Patent number: 8351954
    Abstract: In a PBSS cluster environment, the beacon interval is allocated such that each PBSS in a PBSS cluster possesses its own master sub-beacon interval. Moreover, each member of the PBSS cluster can share unoccupied sub-beacon intervals. When a master PBSS fails to use its own master sub-beacon interval or the beacon intervals which are unoccupied, the available idle time within the beacon interval can be utilized by other member PBSSs in the PBSS cluster. As available or idle beacon interval time is allocated, each master PBSS retains the highest priority to its own master sub-beacon interval thus providing immediate access to a beacon interval when necessary.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: January 8, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George Vlantis
  • Patent number: 8351865
    Abstract: Three alternative methods of controlling transmit power in a basic service set (BSS) including a plurality of stations that have successfully synchronized with an access point include providing each BSS with one transmit power limit that is not more than the lowest one of the transmit power limits of all of its operating channels, providing each BSS with one transmit power limit that is fixed for physical layer convergence procedure (PLCP) protocol data units (PPDU) with each channel bandwidth, or providing each BSS with one transmit power limit that is fixed for each 80 MHz channel.
    Type: Grant
    Filed: December 16, 2010
    Date of Patent: January 8, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8351457
    Abstract: A method for providing a priority-based, low-collision distributed coordination function (DCF) in a wireless network is provided. The network includes an access point and a plurality of stations. The method includes receiving at a first station a super-frame from the access point. The super-frame is operable to define a service period for each of the stations. A priority for the first station is determined based on the super-frame. A back-off time is selected for the first station based on the priority.
    Type: Grant
    Filed: January 16, 2012
    Date of Patent: January 8, 2013
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, Mario Valerio Filauro
  • Publication number: 20120315943
    Abstract: The distribution of the service period (SP) and contention-based period (CBP) scheduling information in the data transfer time (DTT) of a beacon interval (BI) defined under the WGA Draft Specification 0.8 is selectively scheduled to optimize channel access contention. STAs in a single antenna scope or groups of STAs in multiple antennas scopes is allocated to different CBPs to decrease collisions. Simultaneous CBPs is further allocated to STAs in multiple antennas scopes where STAs have peer-to-peer traffic with other STAs in the same antenna group during part of the CBP when the personal PCP/AP is unavailable to that antenna group resulting in an increase in network throughput.
    Type: Application
    Filed: June 7, 2011
    Publication date: December 13, 2012
    Applicant: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8285297
    Abstract: Fair usage of working channels in a wireless network is disclosed. A base station associated with a cell within a wireless community monitors the congestion of the working channel of neighboring communities. Upon determining that the congestion of the working channel of a neighboring community is less than that of its existing working channel, the base station initiates a switch to the neighboring community's working channel. Upon joining the new community, the frame structure and other networking parameters and attributes are adjusted.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: October 9, 2012
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8284775
    Abstract: A six field address scheme identifies both the originating point and the endpoint of a data frame enabling multiple hop forwarding through a plurality of intermediate mesh points in a wireless mesh network. Data frames originating or ending at a point outside of the wireless mesh network access the wireless network at a mesh access point using a legacy address scheme. The legacy address schemes are converted to a six address scheme using a proxy address table at the access point. Each mesh access point includes not only a routing table but a proxy address table as well as enabling the mesh access point, and/or mesh portal points, to convert address schemes having less than six address fields to the six field format. Subsequent to the conversion, mesh points within the wireless mesh network need only the routing table to facilitate the forwarding of the data frame.
    Type: Grant
    Filed: September 9, 2008
    Date of Patent: October 9, 2012
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis
  • Patent number: 8270302
    Abstract: A system and method is disclosed for providing an adaptive value of a TTL (Time to Live) count for broadcast/multicast messages in a wireless mesh network using a hybrid wireless mesh protocol. A mesh point controller is provided that adaptively selects the value of the TTL count and routes the broadcast/multicast message through the wireless mesh network based on the adaptively selected value of the TTL count. The adaptive selection of the TTL count in accordance with the principles of the invention significantly reduces the number of broadcast/multicast messages that must be transmitted (flooded) through the mesh network.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: September 18, 2012
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, Kyeong Soo Kim
  • Patent number: 8249033
    Abstract: A common control channel for base station (“BS”)/consumer premise equipment (“CPE”) communication in areas of overlapping coverage by wireless regional area network (“WRAN”) cells operating on different working channels is disclosed. A common control channel is selected from among the various working channels sensed in each of a plurality of overlapping WRAN cells so as to enable BS/CPE and BS/BS communication. Once chosen, each CPE within the overlapping area communicates with the controlling BS via an enhanced coexistence beacon protocol messages. These messages include timing and other synchronization information.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: August 21, 2012
    Assignee: STMicroelectronics, Inc.
    Inventors: Liwen Chu, Wendong Hu, George A. Vlantis
  • Publication number: 20120163264
    Abstract: Multiple virtual MAC addresses may be added to WGA devices that may have different traffic streams to another device that requires different services, thus creating distinct MAC and device level implications. Beamforming training can be done at the device level for all virtual MAC addresses. Wakeup, doze, and ATIM power save can be done at the device level depending on the frames received. Authentication, deauthentication, association, and deassociation can be done variously at both levels. Further MSDUs can be aggregated for the multiple MAC addresses.
    Type: Application
    Filed: December 22, 2011
    Publication date: June 28, 2012
    Applicant: STMicroelectronics, Inc.
    Inventors: Liwen Chu, George A. Vlantis