Patents by Inventor Bretton Lee Douglas

Bretton Lee Douglas 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: 20150207554
    Abstract: A method and an apparatus in a first wireless station of a network transmitting to a second wireless station. The network uses multi-tone OFDM signals. The first station includes multiple antennas and a receive and a transmit signal path per antenna. Each receive signal path includes a discrete Fourier transformer determining the tones in a received signal, and each transmit signal path includes an inverse discrete Fourier transformer converting tones to a signal. The method includes determining channel estimates for each tone and each receive path while receiving from the second station, determining transmit weights to transmit to the second station, tone-by-tone weighting a signal for transmission to the second station to produce weighted tone sets for each transmit signal path, and transmitting the weighted tone sets. The first station is configured so that the weighting produces additive beamforming without the second station needing multiple antennas.
    Type: Application
    Filed: March 26, 2015
    Publication date: July 23, 2015
    Inventors: Eldad Perahia, Bretton Lee Douglas, Brian Hart, Daniel Joseph Lyons
  • Patent number: 9002299
    Abstract: A method and an apparatus in a first wireless station of a network transmitting to a second wireless station. The network uses multi-tone OFDM signals. The first station includes multiple antennas and a receive and a transmit signal path per antenna. Each receive signal path includes a discrete Fourier transformer determining the tones in a received signal, and each transmit signal path includes an inverse discrete Fourier transformer converting tones to a signal. The method includes determining channel estimates for each tone and each receive path while receiving from the second station, determining transmit weights to transmit to the second station, tone-by-tone weighting a signal for transmission to the second station to produce weighted tone sets for each transmit signal path, and transmitting the weighted tone sets. The first station is configured so that the weighting produces additive beamforming without the second station needing multiple antennas.
    Type: Grant
    Filed: October 1, 2004
    Date of Patent: April 7, 2015
    Assignee: Cisco Technology, Inc.
    Inventors: Eldad Perahia, Bretton Lee Douglas, Brian Hart, Daniel Joseph Lyons
  • Patent number: 8705388
    Abstract: In an example embodiment, a method for determining backhaul channel assignments for multi-channel dual radio mesh nodes. The method comprises acquiring collision domain data for each access point of an associated mesh network. A cost function is calculated for each access point of the associated mesh network, the cost function assigning a weighted value for each access point in a collision domain based on a number of access points in the collision domain. Backhaul channel assignments for selected for each access point that minimizes the cost function.
    Type: Grant
    Filed: November 4, 2010
    Date of Patent: April 22, 2014
    Assignee: Cisco Technology, Inc.
    Inventors: Xiaohong Gong, David S. Stephenson, Johannes P. Kruys, Bretton Lee Douglas
  • Patent number: 8180339
    Abstract: Methods, apparatuses and systems directed to providing network management information to wireless access points in a wireless network. In one implementation, a wireless client interrogates a wireless access point for its MAC address, for service set identifier (SSID) information, and/or for authentication-related information. If the wireless client determines that the wireless access point is the correct wireless access point, the wireless client polls sensors for physical environment and parameter (PEP) data, which the wireless client then transmits to the wireless access point.
    Type: Grant
    Filed: August 9, 2006
    Date of Patent: May 15, 2012
    Assignee: Cisco Technology, Inc.
    Inventors: Bretton Lee Douglas, Gregg Scott Davi
  • Patent number: 8023452
    Abstract: A method including wirelessly receiving a packet at a wireless station belonging to a cell of a wireless network, the network for communicating according to a wireless network standard, each transmitting station of the cell able to transmit a packet that includes cell identification information; and ascertaining at the physical layer level whether or not the received packet is from another station of the cell by ascertaining whether or not the received packet includes the cell identification information of the cell.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: September 20, 2011
    Assignee: Cisco Technology, Inc
    Inventors: Bretton Lee Douglas, Eldad Perahia
  • Patent number: 8023482
    Abstract: A dynamic rate limiting mechanism for wireless mesh networks. In particular implementations, a method comprising monitoring one or more clients associated with a wireless mesh network and the respective hop counts of the clients to a root mesh node of the wireless mesh network; determining, responsive to one or more events, a client data rate for one or more clients of the wireless mesh network based on the number of current clients and the respective hop counts of the current clients; and applying the client data rate to the wireless mesh network.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: September 20, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Xiaohong Gong, Bretton Lee Douglas, Robert B. O'Hara, Jr., Brian Donald Hart
  • Patent number: 8018883
    Abstract: An apparatus, a method, and logic encoded in computer readable media that when executed operable to carry out the method. The method includes wirelessly receiving at a receiving station a signal transmitted from a transmitting station in a wireless network. The signal includes a network identifier, e.g., MAC address of the transmitting station. The method includes determining one or more RF waveform characteristics of at least a transient part of the received signal, decoding the received signal to determine the network identifier, e.g., MAC address, determining one or more behavior characteristics from the received signal; and using the decoded network identifier, e.g., MAC address and a combination of the one or more waveform characteristics and the one or more behavior characteristics to ascertain whether or not the network identifier, e.g., MAC address is a spoofed identifier, the ascertaining using historical samples of combinations for different network identifiers.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: September 13, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Robert A. Bowser, Paul J. Stager, Allan Thomson, Bretton Lee Douglas
  • Patent number: 7978725
    Abstract: Methods, apparatuses and systems directed to facilitating load balancing and bandwidth allocation in wireless mesh networks. Generally, according to one implementation of the present invention, routing nodes implement a contention-based media access mechanism and self-allocate bandwidth within a wireless mesh network by dynamically modifying one or more contention-based transmission control parameters. The routing nodes determine a hop count and adjust one or more contention parameters based at least in part on the hop count.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: July 12, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Xiaohong Gong, Brian Donald Hart, Bretton Lee Douglas
  • Patent number: 7936681
    Abstract: Methods, apparatuses and systems directed to facilitating increased throughput in wireless mesh networks. Generally, according to one implementation of the present invention, routing nodes in a wireless mesh network combine metrics corresponding to the link and network layers to select a route to a root node in the wireless mesh network. In one implementation, for each neighbor, a given routing node computes a routing metric, which is based on the computed route cost and hop count, and selects a preferred neighbor as the parent routing node based on the best routing metric.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: May 3, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Xiaohong Gong, Brian Donald Hart, Bretton Lee Douglas
  • Patent number: 7904092
    Abstract: In one embodiment, a method for adjusting a radio-frequency coverage map. The method includes receiving calibration data comprising observed received signal strength values at one or more calibration points corresponding to a radio frequency transmitter, and identifying an applicable coverage map, where the coverage map provides, for the radio frequency transmitter, estimated received signal strength values at one or more locations. The method also includes determining one or more offset values at the one or more calibration points, where an offset value is based on a difference between an observed received signal strength value and an estimated received signal strength value at a given calibration point. The method also includes adjusting one or more estimated received signal strength values at one or more location bins of the coverage map based on a distance from the one or more calibration points and the one or more offset values.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: March 8, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: Brian Donald Hart, Bretton Lee Douglas
  • Publication number: 20110051619
    Abstract: In an example embodiment, a method for determining backhaul channel assignments for multi-channel dual radio mesh nodes. The method comprises acquiring collision domain data for each access point of an associated mesh network. A cost function is calculated for each access point of the associated mesh network, the cost function assigning a weighted value for each access point in a collision domain based on a number of access points in the collision domain. Backhaul channel assignments for selected for each access point that minimizes the cost function.
    Type: Application
    Filed: November 4, 2010
    Publication date: March 3, 2011
    Inventors: Xiaohong GONG, David S. Stephenson, Johannes P. Kruys, Bretton Lee Douglas
  • Patent number: 7852759
    Abstract: In one embodiment, a method includes receiving a call admission request; in a first state, applying a first call access control (CAC) algorithm to the call admission request; in a second state, applying a second CAC algorithm to the call admission request; and transition between the first state and the second state based on at least one attribute of a radio frequency (RP) environment.
    Type: Grant
    Filed: February 5, 2007
    Date of Patent: December 14, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: David S. Stephenson, Lu Qian, Bretton Lee Douglas, James S. An
  • Patent number: 7849216
    Abstract: In an example embodiment, a method for determining backhaul channel assignments for multi-channel dual radio mesh nodes. The method comprises acquiring collision domain data for each access point of an associated mesh network. A cost function is calculated for each access point of the associated mesh network, the cost function assigning a weighted value for each access point in a collision domain based on a number of access points in the collision domain. Backhaul channel assignments for selected for each access point that minimizes the cost function.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: December 7, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Xiaohong Gong, David S. Stephenson, Johannes P. Kruys, Bretton Lee Douglas
  • Patent number: 7822064
    Abstract: One embodiment includes tracking utilization of the backhaul wireless bandwidth of a mesh network related to time sensitive packet data, receiving a call admission request for a call from a client station of a first mesh access point of the mesh, ascertaining using the tracked utilization whether to approve the call admission request using a backhaul call admission control method, and approving the call by sending a positive call admission response if the backhaul call admission control method approves the call and if an access level call admission control method ascertains to approve the call admission request at the access level.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: October 26, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Pascal Thubert, Patrick Wetterwald, Vincent Jean Ribiere, Bretton Lee Douglas, Johannes Petrus (Jan) Kruys
  • Patent number: 7809020
    Abstract: A method and an apparatus for detecting the start-of-packet in a wireless receiver operating in a packetized wireless network. One method embodiment includes calculating a plurality of start of packet (SOP) indicators, each for one or more of a plurality of receive chains in the receiver; determining one or more linear combinations of respective pluralities of the calculated SOP indicators to form one or more combined SOP indicators; comparing each of a plurality of SOP indicators or combined SOP indicators, including at least one of the combined SOP indicators to a respective threshold to form one or more respective SOP events; and, in the case there is more than one SOP event, determining a logic function of the SOP events to form a SOP decision event.
    Type: Grant
    Filed: June 4, 2007
    Date of Patent: October 5, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Bretton Lee Douglas, Brian D. Hart, Fred J. Anderson, Paul J. Stager, Gregory M. Corsetto
  • Patent number: 7626969
    Abstract: In one embodiment, a method includes computing a probability surface corresponding to the location probability of the wireless node within a physical region based on the received signal strength data associated with a wireless node and an RF model of the physical region; computing, based on the probability surface, an aggregate probability (Pin) of the wireless node being inside a perimeter defined with the physical region; computing, based on the probability surface, an aggregate probability (Pout) of the wireless node being outside the perimeter; computing a probability ratio of the aggregate probabilities Pin to Pout; and determining whether the wireless node is inside or outside the perimeter based on a comparison of Pout and Pin.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: December 1, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Brian Donald Hart, Bretton Lee Douglas
  • Patent number: 7567822
    Abstract: In a wireless LAN (WLAN), methods, apparatuses and systems directed to facilitating configuration of a wireless network is provided. According to one implementation of the present invention, sensors are used to collect data associated with locations and other properties of access points of the wireless network. The collected data can then be used to assist in automatically configuring one or more aspects of the wireless network. In some implementations, the collected data can be used to dynamically re-configure the wireless network in real time. According to another implementation of the present invention, location computation mechanisms are used to collect data associated with the location of one or more wireless clients, and the data is used to dynamically adjust one or more radio frequency (RF) coverage maps in real time. The revised RF coverage maps can then be used to re-configure one or more operational parameters of the wireless network.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: July 28, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Brian Donald Hart, Timothy S. Olson, James Amos, David McClead Theobold, Bretton Lee Douglas
  • Patent number: 7558852
    Abstract: Determining the location of a radio tag or client station of a wireless network, and the location of coverage holes by receiving from a plurality of wireless stations of the wireless network path loss information of the path loss of one or more location frames received at the respective wireless stations. The location frames transmitted by the radio tag or client station having a pre-defined frame structure. The radio tags and client stations use a common infrastructure for transmitting a location frame configured for radiolocation by path loss measurement. The common infrastructure includes a pre-defined protocol common for both radio tags and client stations for transmitting information for reception by the plurality of stations of the wireless network for radiolocation. The pre-defined protocol includes using the location frame having the pre-defined frame structure.
    Type: Grant
    Filed: August 21, 2007
    Date of Patent: July 7, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Bretton Lee Douglas, Timothy S. Olson, David E. Halasz, John Z. Deng, Arnold M. Bilstad, Sheausong Yang, Richard D. Rebo, Jonathan S. Leary, Daryl A. Kaiser
  • Patent number: 7558592
    Abstract: Described herein are a computer-implemented method of determining a power plan/frequency plan combination assigning transmit frequency channels and transmit powers for a plurality of managed access points (APs) of a wireless network. Also described herein is a carrier medium carrying computer readable code configured to cause one or more processors of a processing system to implement the computer implemented method of determining a power plan/frequency plan combination.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: July 7, 2009
    Assignee: Cisco Technology, Inc.
    Inventors: Brian Hart, Bretton Lee Douglas, Lu Qian
  • Publication number: 20090109855
    Abstract: In an example embodiment, a method for determining backhaul channel assignments for multi-channel dual radio mesh nodes. The method comprises acquiring collision domain data for each access point of an associated mesh network. A cost function is calculated for each access point of the associated mesh network, the cost function assigning a weighted value for each access point in a collision domain based on a number of access points in the collision domain. Backhaul channel assignments for selected for each access point that minimizes the cost function.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 30, 2009
    Inventors: Xiaohong Gong, David S. Stephenson, Johannes P. Kruys, Bretton Lee Douglas