Patents Represented by Attorney Van Pelt & Yi LLP
  • Patent number: 6295145
    Abstract: A switchable holographic device generally comprises a substrate having two generally opposed surfaces and a plurality of holographic fringes recorded in the substrate. The holographic fringes are configured to switch between active and passive states upon application of an electrical field. One or more of the plurality of holographic fringes are positioned such that a surface of the fringe is angled relative to one of the substrate surfaces. The holographic device further comprises a pair of electrodes each positioned generally adjacent to one of the substrate surfaces and operable to apply an electrical field to the fringes to switch the fringes between their active and passive states. One of the pair of electrodes has a plurality of independently controlled segments. Each of the segments is positioned over an area of the substrate having holographic fringes positioned within a common range of angles relative to the substrate surface.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: September 25, 2001
    Assignee: Digilens, Inc.
    Inventor: Milan M. Popovich
  • Patent number: 6285334
    Abstract: A slot antenna is described. The slot antenna includes a waveguide having a first side, a second side, a third side, and a fourth side, a closed end and an open end. The second side extends substantially perpendicularly from a first end of the first side. The third side extends substantially perpendicularly from a second end of the first side. The fourth side extends between the second side and the third side with the fourth side substantially parallel to the first side. The sides and the closed end form a cavity. A feeding point is located substantially midway between the first end of the first side and the second end of the first side. A T-Bar is located inside the cavity, the T-bar having a center member extending from the feeding point into the cavity and a cross member having a length extending across the cavity between the second side and the third side.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: September 4, 2001
    Inventors: Gordon Sinclair, Po-shin Cheng
  • Patent number: 6286048
    Abstract: According to an embodiment of the present invention, two routers coupled through a network, such as a local access network (LAN), may be used to serve the function of redundancy to avoid the failure of a connection. The LAN may be used as a backplane to substitute for a bus between two processors. According to an embodiment of the present invention, the two routers may send their medium access control (MAC) addresses to each other and compare these MAC addresses. The router associated with the MAC address that meets a predetermined criteria may be deemed as a primary router and the other router can be deemed as a secondary router. An example of meeting the predetermined criteria is the router associated with the lower MAC address.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: September 4, 2001
    Assignee: Cisco Technology, Inc.
    Inventor: Kenneth Moberg
  • Patent number: 6275458
    Abstract: A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.
    Type: Grant
    Filed: February 18, 1999
    Date of Patent: August 14, 2001
    Inventors: Terrence L. Wong, David C. Lee, Richard L. Martin, Steven R. Spielman
  • Patent number: 6269060
    Abstract: A system and method are disclosed for generating a transition in a laser control signal at a precise point in time. A write strategy processor is configured to input a sequence of data and to determine a transition in a laser control signal from the sequence of data. The transition is specified by a number of pulse clock units and a delay. A write pulse generator is configured to input the number of pulse clock units and the delay and to generate a transition by creating a signal having a transition at the time specified by the number of pulse clock units and delaying the transition by the specified delay.
    Type: Grant
    Filed: September 9, 1999
    Date of Patent: July 31, 2001
    Inventors: Ian E. Harvey, Nugroho Suwito
  • Patent number: 6269452
    Abstract: The present invention provides a protection protocol for fault recovery, such as a ring wrap, for a network, such as a two line bi-directional ring network. An embodiment of the present invention works in conjunction with a ring topology network in which a node in the network can identify a problem with a connection between the node and a first neighbor. The present invention provides a protection protocol which simplifies the coordination required by the nodes in a ring network. The nodes do not need to maintain a topology map of the ring, identifying and locating each node on the ring, for effective protection. Additionally, independently operating ring networks can be merged and the protection protocol will appropriately remove a protection, such as a ring wrap, to allow the formation of a single ring.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: July 31, 2001
    Assignee: Cisco Technology, Inc.
    Inventors: Feisal Daruwalla, Hon Wah Chin, David Tsiang, George Suwala, Tony Bates
  • Patent number: 6260070
    Abstract: An embodiment of the present invention is a system and method for selecting a mirrored service in a network, such as the Internet, by utilizing a Border Gateway Protocol (BGP) attribute. According to an embodiment of the present invention, the BGP attribute, which may be stored in a border router, is accessed for each mirrored service for a prefix associated with the user requesting a host name. The attributes from each mirrored service are compared with each other to determine a “best” attribute which meets a predetermined criteria. The mirrored service associated with the best attribute is then selected as a resolution for the host name.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: July 10, 2001
    Inventor: Dhaval N. Shah
  • Patent number: 6256324
    Abstract: Provided is a system which automatically determines and assigns an appropriate address for each chip in repeater system. All the ASICs in a system are chained together on a serial data ring for address allocation purposes. A “First On” ASIC in a system initializes the chip address map, assigns itself the first address. The First On ASIC then updates the address map by setting the next address and sends it down the chain to the next ASIC in the system. The second ASIC allocates the incoming address to itself, sets the address for the next ASIC, and passes the address signal on. The process repeats itself until the last ASIC in the chain has an address allocated. The last ASIC the notifies the First On ASIC of its address to close the loop.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: July 3, 2001
    Assignee: Cisco Technology, Inc.
    Inventor: Moshe Voloshin
  • Patent number: 6249507
    Abstract: Storage density in an optical data storage media and system is increased many times the resolution limit by fully utilizing the much smaller detection limit by differentiating and isolating the active data sites in the media optically. The tracks are preordained and predisposed to a specific optical property and value that is different from that of its “n” nearest neighbors but is identical to its nth neighbor and to the optical properties of the reading and writing optical system.
    Type: Grant
    Filed: August 15, 2000
    Date of Patent: June 19, 2001
    Inventor: John M. Guerra
  • Patent number: 6243826
    Abstract: Provided is a redundant network management system. Several network management modules (NMMs), preferably one for each repeater unit, are provided in a single repeater stack. The NMMs of the repeater stack communicate using a management bus. The modules communicate on the management bus by sending small messages, referred to as “frames.” In a preferred embodiment, the present invention is preferably used in conjunction with a relatively simple and economical 8-bit management bus. This low cost implementation allows only one NMM to access the bus at any given time, and makes use of protocols by which multiple NMMs may use the management bus to communicate while ensuring that no two modules attempt to use the bus at the same time. Moreover, according to the present invention, only one NMM (referred to as the “master”) will perform all of the network management functions for the stack at any one time. The remaining modules operate in “slave” mode.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: June 5, 2001
    Assignee: Cisco Technology, Inc.
    Inventors: Tuyen V. Quoc, Alan P. Liebthal
  • Patent number: 6206584
    Abstract: An object code expansion program inserts new instructions and data between preexisting instructions and data of an object code file; offsets are modified to reflect new positions of the preexisting instructions and data. For each item of preexisting object code (instructions or data), the following steps are performed: making a new code block comprising any desired new instructions and the item, and storing it as new object code; tracking the location of the item and the new code block within the new object code; and tracking items that contain inter-item offsets. Then, each inter-item offset is updated using the new location of the item or new code block, as required. Finally, offsets in symbol tables and relocation structures are updated with the new location of the item. This expansion program is used to add instructions to object code files of a second program, to monitor substantially all of the memory accesses of the second program.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: March 27, 2001
    Assignee: Rational Software Corporation
    Inventor: Reed Hastings
  • Patent number: 6195107
    Abstract: The present invention provides a system and method for reducing memory requirements in a low resource computer system. Although examples herein are described in terms of embedded systems, the present invention is equally applicable to other low resource computer systems, such as palmtops, and laptops. Memory requirements, such as RAM requirements, can be reduced by combining virtual memory with a secondary memory with statically compressed contents. According to embodiments of the present invention, executable image of memory, such as the image of RAM, is compressed at image production time. The compressed image is then stored in a non-volatile memory, such as FLASH memory. At run-time, when a request identifying a virtual address is received, it is determined whether a physical address in the physical memory, such as RAM, is associated with that virtual address. If there is no physical memory associated with that virtual address, then a physical address is obtained to be associated with that virtual address.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: February 27, 2001
    Assignee: Cisco Technology, Inc.
    Inventor: Timothy J. Iverson
  • Patent number: 6192026
    Abstract: A medium access contention protocol that is highly beneficial in wireless networks and particularly in wireless networks that employ a fixed minimum burst size such as OFDM wireless networks. In one embodiment, a MAC protocol is a demand-assigned protocol that maximizes utilization of the bus medium (the allocated frequency spectrum.) Each data communication device (DCD) in the network communicates with a central access point (AP). Multiple DCDs may request access from the AP in the same request access (RA) burst. Each of the multiple DCDs transmits its access request to the AP within a frequency domain channel in the RA burst that is orthogonal to the frequency domain channels used by the other DCDs requesting access. Each DCD includes channel training information in the access request burst to allow the AP and/or DCD to adapt to rapid variations in channel characteristics.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: February 20, 2001
    Assignee: Cisco Systems, Inc.
    Inventors: Michael A. Pollack, Vincent K. Jones, Gregory G. Raleigh
  • Patent number: 6178176
    Abstract: Provided is a synchronous stack bus repeater system for a computer network. The system includes a plurality of stacked repeaters, a stack bus linking the repeaters, and a single clock to which the plurality of repeaters is synchronized. The synchronization of the stack bus eliminates several time-consuming communications required between devices operating with different clocks on an asynchronous bus and makes it possible to satisfy the 46 bit time repeater maximum latency required of a Class II repeater according to the IEEE 802.3 standard.
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: January 23, 2001
    Assignee: Cisco Technology, Inc
    Inventors: Moshe Voloshin, Mark D. Cavaro
  • Patent number: 6176733
    Abstract: A system and method are disclosed for providing a failover for designating a primary network device and a backup network device and providing direct communication between the primary network device and the backup network device. The cable includes a plurality of conductive wires having a primary end and a backup end. A primary connector is connected to the plurality of conductive wires at the primary end of the plurality of conductive wires. The primary connector has a primary plug driver pin and a primacy select pin, and the primary plug driver pin is connected to the primacy select pin. A backup connector is connected to the plurality of conductive wires at the backup end of the plurality of conductive wires, the backup connector has a grounded pin and a backup select pin and the backup grounded pin is connected to the backup select pin. Thus, the primary end of the failover cable is distinguishable from the backup end of the failover cable.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: January 23, 2001
    Assignee: Cisco Technology, Inc.
    Inventors: Brantley W Coile, James A. Jordan
  • Patent number: 6175631
    Abstract: A system and method are described for rendering a left rear surround input signal at a left rear virtual speaker location and rendering a right rear surround input signal at a right rear virtual speaker location. The method includes phase shifting the left rear surround input signal by a first phase shift. The right rear surround input signal is phase shifted by a second phase shift. The phase shifted left rear surround input signal is phase shifted using an HRTF selected to render the left rear surround input signal at the left rear virtual speaker location. The phase shifted right rear surround input signal is transformed using an HRTF selected to render the right rear surround input signal at the right rear virtual speaker location.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: January 16, 2001
    Inventors: Stephen A. Davis, Martin Walsh, David Berners
  • Patent number: 6174092
    Abstract: A method of aligning an optical fiber for coupling light to or from an optical device and fixing the optical fiber to an optical fiber support is disclosed. The method includes positioning the optical fiber into alignment with the optical device. An adapter is positioned between the optical fiber and the optical fiber support. The adapter is formed to substantially fill a gap between the optical fiber and the optical fiber support. The adapter is fixed to the optical fiber support and the adapter is fixed to the optical fiber.
    Type: Grant
    Filed: January 11, 1999
    Date of Patent: January 16, 2001
    Assignee: OESYS Photonics, Inc.
    Inventor: Sabeur Siala
  • Patent number: 6167534
    Abstract: An improved system and method for load testing software applications is provided. The user interface and/or application calls are captured to generate a script to emulate a user session. The script may include source language statements and, with or without editing, may be compiled into an executable script. Multiple scripts may be executed on a script driver to simulate multiple users to load test a system.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: December 26, 2000
    Assignee: Rational Software Corporation
    Inventors: Jeffrey A. Straathof, Joel L. Sherriff, Dawn C. Maurer, Ramendra S. Chhina
  • Patent number: 6167465
    Abstract: Accordingly, the present invention provides a method and an apparatus of establishing multiple direct memory access connections between a peripheral and a main memory of a computer system. Each of the multiple direct memory access connection is managed in an improved manner such that one or more of the multiple direct memory access connections are non-real-time connections, but real-time operations may be performed on the data carried by the non-real time connections. In another aspect of the present invention, a driver may be implemented on the computer system to facilitate the establishment and maintenance of the multiple direct memory access connections. The present inventions reduce arbitration and system interrupt latencies and reduces the management burden of the direct memory access connections on a central processing unit of the computer system.
    Type: Grant
    Filed: May 20, 1998
    Date of Patent: December 26, 2000
    Assignee: Aureal Semiconductor, Inc.
    Inventors: Shaham Parvin, Gary M. Catlin
  • Patent number: D436629
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: January 23, 2001
    Assignee: Digilens, Inc.
    Inventors: David Henley Fawkes, Richard Holmes