Patents Assigned to Broadcom Corporation
  • Patent number: 7515891
    Abstract: A method and apparatus for dynamically controlling a programmable gain amplifier (PGA) to provide a plurality of gain steps thereby providing automatic gain control (AGC) in a receiver intermediate frequency (IF) stage comprising a succession of operational amplifiers wherein at least one is for providing fine gain control and wherein the gain of each fine gain amplifier is controlled by the resistance ratios of a plurality of selectively biased MOSFETs. In one embodiment of the invention, three coarse amplifiers are provided, each having a gain of either 0 dB or 12 dB based on the value of a two-state signal provided to each amplifier gain control input. A single fine gain amplifier has a gain of 0 dB, 3 dB, 6 dB or 9 dB based on the binary value of the two-bit signal provided to the amplifier.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: April 7, 2009
    Assignee: Broadcom Corporation
    Inventor: Hooman Darabi
  • Patent number: 7515592
    Abstract: A network device for processing a packet can include an ingress port configured to receive the packet. In addition, the network device can include a membership port bit map table configured to store at least one membership port bit map, an outgoing port bit map table configured to store at least one outgoing port bit map. A first storage unit within the network device can be configured to store an egress port bit map. The egress port bit map is based on the membership port bit map and the outgoing port bit map. Furthermore, the network device can have at least one egress port configured to transmit out the packet. The at least one egress port can correspond to the egress port bit map.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: April 7, 2009
    Assignee: Broadcom Corporation
    Inventors: Laxman Shankar, Shekhar Ambe
  • Publication number: 20090086808
    Abstract: Improved decision feedback equalizer and decision directed timing recovery systems and methods suitable for use in connection with a dual mode QAM/VSB receiver system are disclosed. A trellis decoder operates in conjunction with a decision feedback equalizer circuit on trellis coded 8-VSB modulated signals. The trellis decoder includes a 4-state traceback memory circuit outputting a maximum likelihood decision as well as a number of intermediate decisions based upon the maximum likelihood sequence path. Any number of decisions, along the sequence, may be provided as an input signal to timing recovery system loops, with the particular decision along the sequence chosen on the basis of its delay through the trellis decoder. Variable delay circuitry is coupled to the other input of the timing recovery system loops in order to ensure that both input signals bear the same timestamp.
    Type: Application
    Filed: December 8, 2008
    Publication date: April 2, 2009
    Applicant: Broadcom Corporation
    Inventors: Tian-Min Liu, Loke Kun Tan, Steven T. Jaffe
  • Publication number: 20090085597
    Abstract: A system or apparatus for monitoring an Integrated Circuit (IC) chip includes: a sense circuit at least partially constructed on the IC chip and configured to produce one or more sense signals each indicative of a corresponding process-dependent circuit parameter of the IC chip; and a digitizer module configured to produce, responsive to the one or more sense signals, one or more digitized signals each representative of a corresponding one of the sense signals. A controller is configured to determine a value of one or more of the process-dependent circuit parameters based on one or more of the digitized signals.
    Type: Application
    Filed: October 30, 2008
    Publication date: April 2, 2009
    Applicant: Broadcom Corporation
    Inventors: Lawrence M. Burns, Leonard Dauphinee, Ramon A. Gomez, James Y.C. Chang
  • Publication number: 20090085761
    Abstract: The present invention provides systems, methods, and computer program products for identifying possible attempts to tamper with a terminal using geographic position data. For a terminal, a geographic usage policy is defined that identifies an allowable geographic operational zone for the terminal. The geographic usage policy may also include corrective action or actions based on violations of the usage policy. The type of corrective action may vary based on the details associated with the violation (e.g., distance from the operational zone, time of day, etc.). A tamper identification module receives geographic position data from a global positioning system within the terminal. The tamper identification module then determines whether the received position data is within the allowable geographic operation zone for the terminal. If the position data is not within the allowable geographic operation zone, then the appropriate corrective action is performed.
    Type: Application
    Filed: September 26, 2008
    Publication date: April 2, 2009
    Applicant: Broadcom Corporation
    Inventor: Mark BUER
  • Patent number: 7512186
    Abstract: A method for enhancing the bit rate and/or margin at which quadrature amplitude modulation (QAM) communication is performed over multiple bands of a communication link includes the steps of varying a spectral allocation and constellation size with which communication is performed, so as to define a combination of spectral allocation and constellation size at which the bit rate and/or margin are enhanced. The rate adaptation method identifies the spectral allocation and constellation size to use on each of the multiple bands that results in a total bit rate greater than or equal to the target bit rate, subject to specified constraints on SNR margin and/or BER limits. If more than one parameter set has this property, the rate adaptation method may for example select the spectral allocation and constellation size combination that maximizes the minimum SNR margin across the multiple bands.
    Type: Grant
    Filed: August 5, 2005
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventor: David Charles Jones
  • Patent number: 7511768
    Abstract: A media processing system for limiting ringing in a filter output. A detection filter receives a media signal and generates a detection signal. The detection signal has a constant value over sections of the media signal having a consistent DC bias. The value of the detection signal changes when the DC bias of the media signal changes. The control module receives the detection signal and determines if the media signal may result in ringing based on the detection signal. If it is determined the media signal may result in ringing, a smoothing filter is applied to the media signal.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Chuck Monahan, Darren Neuman
  • Patent number: 7512535
    Abstract: A filter controller processes a decoded speech (DS) signal. The DS signal has a spectral envelope including a first plurality of formant peaks having different respective amplitudes. The controller produces, from the DS signal, a spectrally-flattened DS signal that is a time-domain signal. The spectrally-flattened time-domain DS signal has a spectral envelope including a second plurality of formant peaks. Each of the second plurality of formant peaks approximately coincides in frequency with a respective one of the first plurality of formant peaks. Also, the second plurality of formant peaks have approximately equal respective amplitudes. Next, the controller derives, from the spectrally-flattened time-domain DS signal, a set of filter coefficients representative of a filter response that is to be used to filter the DS signal.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Juin-Hwey Chen, Jes Thyssen
  • Patent number: 7512154
    Abstract: A number of features for enhancing the performance of a wireless communication system, in which data is transmitted between a central node and a plurality of subscriber nodes located remotely with respect to the central node, are presented. The power transmission level, slot timing, and equalization of the subscriber nodes are set by a ranging process. Data is transmitted by the subscriber nodes in fragmented form. Various measures are taken to make transmission from the subscriber nodes robust. The uplink data transmission is controlled to permit multiple access from the subscriber nodes.
    Type: Grant
    Filed: October 11, 2006
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Thomas J. Quigley, Jonathan S. Min, Lisa V. Denney, Henry Samueli, Sean F. Nazareth, Feng Chen, Fang Lu, Christopher R. Jones
  • Patent number: 7511582
    Abstract: The present invention provides a clock circuit to produce a Reference Clock Signal used to latch data between first bit stream(s) and second bit stream(s), wherein the number and bit rate of the first bit stream(s) and the second bit stream(s) differ. The VCO generates one of a number of inputs to a PLL within the clock circuit. At a minimum, these inputs include a first bit stream data clock. Additionally, these inputs may further include a Loop Timing Clock Signal, an External Reference Clock Signal, and/or a Reverse Clock Signal for the PLL. The input provided by the VCO make up a VCO Output Signal wherein a filtering circuit that circuit includes a capacitor and a resistor reduces noise contained within the VCO Output Signal.
    Type: Grant
    Filed: July 21, 2003
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventor: Guangming Yin
  • Patent number: 7510121
    Abstract: Portable measuring devices which communicate by low power transceivers through a communication controller with a printer device collect weight and size data on articles to be shipped. The collected weight and size data are combined with origin and destination data, and labels are printed bearing pertinent shipping and routing information in machine readable format. The labels are attached to the articles to be shipped and accompany the articles to their respective destinations. At transfer points the labels are read by scanner devices which also communicate by low power transceiver links with the communication controller. The wireless linking of the scanner devices promotes human safety by the absence of cords which could cause entanglement of an operator in mechanized conveying equipment. The communication controllers at each stage of the shipping process have the capability of transferring received and updated status information on the shipped articles to a central data station.
    Type: Grant
    Filed: May 22, 2006
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Steven E. Koenck, Alan G. Bunte, Keith K. Cargin, Jr., George E. Hanson, Ronald L. Mahany, Phillip Miller, Steven H. Salvay, Arvin D. Danielson, Guy J. West
  • Patent number: 7512144
    Abstract: Certain aspects of the present invention for transmission control protocol (TCP) retransmission processing may comprise receiving a request for packet retransmission to be processed by an offload network interface card (NIC). A remote peer, a retransmission timer, or a fast retransmission signal may initiate the request. The NIC processes the request information and sends notification to the host of the request. The host searches the TCP buffers of the TCP transmission window in host memory for the packet. Once the packet is located, the host may send the offload NIC the buffer descriptors containing data that locates the packet in host memory. The offload NIC may retrieve the packet from host memory and may retransmit the packet according to the request information. The offload NIC may send notification to the host that the packet has been retransmitted.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventor: Kan Frankie Fan
  • Patent number: 7512752
    Abstract: Presented herein are system(s) and apparatus for a memory access unit for accessing data for a module. The memory access unit comprises an output port for providing access requests for lists of addresses in a memory over a link to a memory controller.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventor: Alexander G. MacInnis
  • Patent number: 7512423
    Abstract: A radio receiver includes a power control module for selectively powering down and powering up radio receiver elements in between known communication periods according to one aspect of the present invention. According to a second aspect of the invention, the radio receiver operates in a low power mode of operation and periodically “sniffs” to determine whether an access point has messages or communication signals to transmit to it.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventor: Jeyhan Karaoguz
  • Patent number: 7512199
    Abstract: The present invention provides a processing module operable to produce an improved channel impulse response. This process involves initially estimating the channel impulse response. This result is based on and combined with a known sequences such as that provided by training sequences of the midamble within RF bursts. From this combination, it is possible to produce an estimated signal from a convolution of the channel impulse response and midamble. The estimated signal may be cancelled or subtracted from the received signal to produce a clearer image of the disturber signal. A blind data recovery performed upon the disturber signal. The recovered disturber data may be used as a reference for disturber channel estimation in order to produce a disturber channel impulse response. With the estimated disturber channel impulse response and the recovered disturber data, an estimated disturber signal may be reconstructed and subtracted from the received signal.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Arkady Molev-Shteiman, Arie Heiman, Huaiyu (Hanks) Zeng
  • Patent number: 7512378
    Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: March 31, 2009
    Assignee: Broadcom Corporation
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran, Meng-An Pan, Hung-Ming Chien, Shahla Khorram, William T. Colleran, Jacob Rael, Masood Syed, Brima Ibrahim, Stephen Wu, Shervin Moloudi
  • Publication number: 20090079558
    Abstract: A midspan power sourcing equipment (PSE) for operation with power over Ethernet (PoE). The midspan PSE provides powering over wire pairs that are also used for data communication. To reduce costs by the midspan manufacturer, the midspans can be designed without the use of data transformers. Rather, midspans can include transmit/receive couplers that have blocking capacitors and divider trees for the insertion of power.
    Type: Application
    Filed: September 25, 2007
    Publication date: March 26, 2009
    Applicant: Broadcom Corporation
    Inventor: Wael William Diab
  • Publication number: 20090080135
    Abstract: Methods and apparatus for substrates with electrostatic discharge (ESD) protection are described. A substrate includes first and second ground planes and a trace that couples the first ground plane to the second ground plane. A signal passed by the first ground plane resulting from an electrostatic discharge (ESD) event interacts with a signal passed by the second ground plane resulting from the ESD event. The first and second ground planes are substantially isolated from each other when the first and second ground planes are coupled to a ground plane of a printed circuit board (PCB).
    Type: Application
    Filed: July 22, 2008
    Publication date: March 26, 2009
    Applicant: Broadcom Corporation
    Inventor: Donald Edward MAJOR
  • Publication number: 20090079629
    Abstract: An integrated circuit, for use in a GPS device, includes an on-chip gyrating circuit that generates a motion parameter based on motion of the IC. A global positioning system (GPS) receiver receives a GPS signal and generates GPS position data based on the GPS signal. A processing module processes the motion parameter to produce motion data and that generates position information based on the GPS position data.
    Type: Application
    Filed: December 4, 2008
    Publication date: March 26, 2009
    Applicant: Broadcom Corporation
    Inventor: Ahmadreza Reza Rofougaran
  • Publication number: 20090083550
    Abstract: A midspan power sourcing equipment (PSE) that supports four-pair powering in a power over Ethernet (PoE) applications. The midspan PSE can provide power to two separate end devices using a single cable. To ensure compatibility with legacy Ethernet devices, the ports used for transmission of data are designed with a sufficient inductance level or a low effective impedance at a frequency of operation.
    Type: Application
    Filed: September 25, 2007
    Publication date: March 26, 2009
    Applicant: Broadcom Corporation
    Inventor: Wael William Diab