Patents Assigned to Broadcom
  • Publication number: 20100310024
    Abstract: Digital signal processing based methods and systems for receiving data signals include parallel receivers, multi-channel receivers, timing recovery schemes, and, without limitation, equalization schemes. The present invention is implemented as a multi-path parallel receiver in which an analog-to-digital converter (“ADC”) and/or a digital signal processor (“DSP”) are implemented with parallel paths that operate at lower rates than the received data signal. In an embodiment, a parallel DSP-based receiver in accordance with the invention includes a separate timing recovery loop for each ADC path. In an embodiment, a parallel DSP-based receiver includes a separate automatic gain control (AGC) loop for each ADC path. In an embodiment, a parallel DSP-based receiver includes a separate offset compensation loop for each ADC path. In an embodiment, the present invention is implemented as a multi-channel receiver that receives a plurality of data signals.
    Type: Application
    Filed: August 16, 2010
    Publication date: December 9, 2010
    Applicant: Broadcom Corporation
    Inventors: Oscar Agazzi, Venugopal Gopinathan
  • Publication number: 20100312910
    Abstract: According to one example embodiment, an apparatus may include a media-side physical layer (PHY) block configured to receive a received signal via at least one medium, decode the received signal into data, and send the data to a media-side medium access control (MAC) block, the media-side MAC block configured to receive the data from the media-side PHY layer block, determine a time of receipt of the data, prevent a system-side MAC block from forwarding the data until a predetermined delay after the time of receipt, perform MAC functions on the data, and send the data to the system-side MAC block, the system-side MAC block configured to receive the data and the control time from the media-side MAC block and send the data to a system-side PHY block after the predetermined delay based on signals received from the media-side MAC block, and the system-side PHY block configured to receive the data from the system-side MAC block, encode the data into a transmitted signal, and transmit the transmitted signal to a comp
    Type: Application
    Filed: August 28, 2009
    Publication date: December 9, 2010
    Applicant: Broadcom Corporation
    Inventors: Meg Lin, Daniel Tai
  • Publication number: 20100309848
    Abstract: Transmission coordination within multiple user, multiple access, and/or MIMO wireless communications. Within wireless communication systems, there can be various wireless communication devices therein that are not all compliant with a common capability set, communication protocol, communication standard, recommended practice, etc. For example, some communication systems may have some wireless communication devices characterized as ‘legacy’ wireless communication devices, and other wireless communication devices therein may be newer and compliant with newer capability sets, communication protocols, communication standards, recommended practices, etc. In such instances, coordination of transmissions among the various wireless communication devices may be made, when performing simultaneous transmissions, by ensuring that transmissions of devices on different channels is made when aligned on a common boundary of an OFDM symbol.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 9, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: VINKO ERCEG, JOSEPH PAUL LAUER, MATTHEW JAMES FISCHER, PEIMAN AMINI, JOONSUK KIM
  • Publication number: 20100309935
    Abstract: A method and system of processing sampled voice packets from a voice packet sender for transmission over a bit-rate sampled data transmission system, such as by a cable modem over a cable modem termination system, to a voice packet recipient. Unsolicited grant arrivals in response to a request from the voice packet sender coupled to the cable modem are determined. The storing of sampled voice packets is synchronized with the unsolicited grant arrivals. Upon receipt of an unsolicited grant arrival, currently stored sampled voice packets are transmitted to the cable modem for further transmission to the voice packet recipient over the cable modem termination system.
    Type: Application
    Filed: August 16, 2010
    Publication date: December 9, 2010
    Applicant: Broadcom Corporation
    Inventors: Theodore F. Rabenko, James C.H. Thi, John D. Horton, JR.
  • Publication number: 20100311432
    Abstract: Cluster parsing for signaling within multi-user wireless communication systems. Cluster assignment allows for complete flexibility across a variety of operational parameters in accordance with communications provided from a transmitting wireless communication device to a number of receiving wireless communication devices. For example, an access point (AP) may communicate to a number of wireless stations (STAs) in accordance with multi-user multiple input multiple output (MU-MIMO), orthogonal frequency division multiple access (OFDMA), and/or MU-MIMO/OFDMA. The selectivity may involve employing different antenna for communicating with each of the respective, receiving wireless communication devices. Also, the formation of a cluster employed in such communications may involve using as few as one channel within one band, different channels within a single band, different channels within different bands, or other combinations.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 9, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: JOSEPH PAUL LAUER, JOONSUK KIM, VINKO ERCEG, MATTHEW JAMES FISCHER, PEIMAN AMINI
  • Publication number: 20100309834
    Abstract: Channel characterization and training within multiple user, multiple access, and/or MIMO wireless communications. Within such communication systems, there can be a number of devices (e.g., STAs) that communicate with a single device (e.g., AP). A multi-cast sounding frame may be transmitted from a transmitting device to a number of receiving devices. Appropriate scheduling or ordering of feedback signals from some or all of the receiving devices may be performed explicitly (e.g., sounding frame sent from the transmitting device to a receiving device) or implicitly (e.g., control information sent from the transmitting device to the receiving device, sounding frame sent to the transmitting device from the receiving device). Such characterization and training is with respect to a channel or path in which data will subsequently follow. Such characterization and training can be performed in accordance with group membership (e.g., with respect to only some of the receiving devices).
    Type: Application
    Filed: June 8, 2010
    Publication date: December 9, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: MATTHEW James FISCHER, JOONSUK KIM, PEIMAN AMINI, JOSEPH PAUL LAUER, VINKO ERCEG
  • Publication number: 20100310002
    Abstract: Adaptive and selective frame formats within multiple user, multiple access, and/or multiple input multiple output (MIMO) wireless communications. A reconfigurable channel circuitry, that may be implemented to communicate with one, a subset, or all of various blocks within a communication device provides for adaptive and selective frame formatting of communications between the communication device and other communication devices. In a wireless communication device context, and also in the context of multiple user, multiple access, and/or MIMO communications (e.g., multi-user multiple input multiple output (MU-MIMO) and/or orthogonal frequency division multiplexing (OFDM), etc.), frame formatting may be adapted in accordance with a number of parameters including: the one or more users with which communications are to be made, the clusters (e.g., channel, band, frequency, etc.) employed for such communications, the one or more antennae (e.g.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 9, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: JOSEPH PAUL LAUER, VINKO ERCEG, PEIMAN AMINI, MATTHEW JAMES FISCHER, JOONSUK KIM
  • Publication number: 20100308918
    Abstract: Embodiments of the present invention provide systems and methods for automatic amplifier gain profile control, including a method for automatically configuring a variable gain profile amplifier according to received input and a variable gain profile amplification system. Further, embodiments of the present invention provide systems and methods for increased gain profile accuracy, including methods and systems to reduce the effects of temperature and/or process variations on the gain profile of an amplifier.
    Type: Application
    Filed: August 13, 2010
    Publication date: December 9, 2010
    Applicant: Broadcom Corporation
    Inventors: Ramon Gomez, Jianhong Xiao, Takayuki Hayashi
  • Publication number: 20100313030
    Abstract: A technique to ensure watermarking a highest selected layer for decoding when receiving a scalable coded bitstream having a plurality of bitstream layers. In one technique, the watermark is associated only with the highest layer that is selected from the hierarchically arranged layers and not in any of the lower layers of the hierarchy. In another technique, the watermarks are present in all the layers, but each lower layer watermark is compensated in a next higher layer to remove effects of the presence of the lower layer watermark in the next higher layer.
    Type: Application
    Filed: June 4, 2009
    Publication date: December 9, 2010
    Applicant: Broadcom Corporation
    Inventors: Zhijie Yang, Wade Wan, Brian Heng
  • Patent number: 7849418
    Abstract: Segregation of redundant control bits in an ECC permuted, systematic modulation code. Appropriately encoding of user information via combined modulation and RS (Reed-Solomon) encoding ensures segregation of scrambled user information, modulation redundancy bits, and RS redundancy bits in such a way that each of the components thereof are segregated and stored within any desirable digital information memory storage device. By providing this segregated capability, when accessing a portion of a RS codeword from the memory, an entire RS codeword need not be read from the memory. In fact, only the particular field (or bits) needs to be accessed to perform correction thereon. This segregation provides for a reduction in the hardware complexity of translation between user information and a modulation codeword. Also, this segregation provides for the ability to perform correction of only one of the scrambled user information, the modulation redundancy bits, or the RS redundancy bits.
    Type: Grant
    Filed: January 11, 2008
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: John P. Mead
  • Patent number: 7848428
    Abstract: In video compression systems, a system and method for reducing visible artifacts in video coding using multiple reference pictures are provided. A first GOP characterized by a “bbIbbBbbBbbB” structure and a second GOP characterized by “bbIbbQbbMbbQ” GOP structure may be used to reduce “I” frame clicking. The “B,” “b,” “Q,” and “M” pictures may be inter-coded by using multiple prediction dependencies, including dependency to a next GOP “I” picture, to smooth out discontinuities across GOPs in a video sequence. Prediction dependencies may be based on a weighing scheme where assigned weights are a function of the temporal distance between reference pictures and the picture being encoded. A first video compression system may be used for the first GOP and may encode “I,” “B,” and “b” pictures. A second video compression system may be used for the second GOP and may encode “I,” “Q,” “M,” and “b” pictures.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Douglas Chin
  • Patent number: 7848704
    Abstract: A method, apparatus, and system for tracking and locating BT enabled devices is described. A network of BT sniffers can be used to rapidly locate lost devices and their owners. Wearable child devices maintain low power contact with parent devices until such time as a signal limit is reached, at which point the parent devices alarm. An optional network of fixed sniffing devices can be used to coordinate a search for lost child devices once an alert is issued to the system.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Sherry Smith
  • Patent number: 7848453
    Abstract: A transmitter includes a first amplifier to amplify an in-phase oscillator signal to produce an in-phase mixing signal and a second amplifier to amplify a quadrature-phase oscillator signal to produce a quadrature-phase mixing signal. A first mixer mixes the in-phase mixing signal with a first information signal to produce a first output signal. A second mixer mixes the quadrature-phase mixing signal with a second information signal to produce a second output signal. The first output signal and an inverted second output signal are summed to produce a transmitter output signal that includes an image signal caused by a phase imbalance between the in-phase and quadrature-phase mixing signals. An image monitor monitors the image signal and reduces or eliminates the phase imbalance by independently adjusting a phase of the in-phase mixing signal and/or a phase of the quadrature-phase mixing signal. Consequently, a power of the image signal is reduced or eliminated.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Meng-An Pan
  • Patent number: 7849211
    Abstract: Aspects of a method and system for reliable multicast datagrams and barriers are presented. Various aspects of the system may include a hub that enables storage of data received from a data source in a multicast group. The data source may be associated with a computer in a distributed cluster computing system. The hub may enable multicast of the received data to a plurality of data destinations in the multicast group. The data destinations may be associated with a corresponding plurality of computers in the distributed cluster computing system. The hub may enable reception of an acknowledgement from each of the plurality of data destinations. The hub may enable an acknowledgement to be sent to the data source.
    Type: Grant
    Filed: May 12, 2006
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Caitlin Bestler
  • Patent number: 7848293
    Abstract: A system and method for automatic wireless transport selection for increased performance and reduced power consumption. Multiple wireless transport services can appear to a TCP/IP stack as a single adapter. Management of the multiple wireless transport services can be performed below the TCP/IP stack to optimize on criteria such as power consumption and bandwidth.
    Type: Grant
    Filed: May 9, 2007
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventors: Victor Zhodzishsky, Ash Kapur
  • Patent number: 7848394
    Abstract: A first serial transceiver has a reference clock, a first transmitter, and a first receiver. The first receiver includes (i) a phase detector, and (ii) a phase rotator. The phase rotator is driven by the reference clock. A first multiplexer is coupled to the first receiver. The first multiplexer receives the phase detector output and a control signal. When the first serial transceiver is in a test configuration, the first multiplexer passes the control signal to the phase rotator, thereby varying the frequency of the phase rotator output. A second multiplexer is coupled to the first transmitter. The second multiplexer receives a reference clock signal and the phase rotator output. When the first serial transceiver is in a test configuration, the second multiplexer passes the phase rotator output to the first transmitter. The first transmitter thereby transmits a serial data stream that varies in frequency from said reference clock.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventors: Raymond L. Clancy, Michael Q. Le
  • Patent number: 7849208
    Abstract: A system for processing packets is disclosed and may including a network interface card (NIC). The NIC may include a TCP enabled Ethernet controller (TEEC). The TEEC may include an internal elastic buffer. The TEEC may process received incoming TCP packets once and may temporarily buffer at least a portion of the incoming TCP packets in the internal elastic buffer. The processing may occur without reassembly or retransmission. The internal elastic buffer may include a receive internal elastic buffer and a transmit internal elastic buffer. The receive internal elastic buffer may temporarily buffer at least a portion of the received incoming TCP packets. The transmit internal elastic buffer may temporarily buffer at least a portion of TCP packets to be transmitted. The TEEC may place at least a portion of the received incoming TCP packets data into at least a portion of a host memory.
    Type: Grant
    Filed: February 18, 2008
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventors: Uri Elzur, Frankie Fan, Steven B. Lindsay, Scott S. McDaniel
  • Patent number: 7848930
    Abstract: A system and method for controlling rate adjustment of audio data to prevent underflow or overflow. In a dual audio/video system, a device can receive two input transport streams. To prevent underflow or overflow of audio data when audio data from a first transport stream is displayed in accordance with a sample rate derived from a second transport stream, a control for rate adjustment is used to match the source sample rate with the display rate. This rate adjustment module can be designed to add or drop audio samples based on a time base comparison or on a STC, PTC, and display rate comparison.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Cam Minh Luu
  • Patent number: 7848709
    Abstract: In one embodiment of the present invention, two crystal oscillator circuits are coupled in parallel to provide differing performance according to mode. Generally, a first circuit provides low phase noise and high accuracy while a second circuit provides greater phase noise within an acceptable tolerance while consuming significantly less power in a low power mode of operation. The second circuit includes an entirely separate amplifier for the low power operation that tolerates a relatively smaller input signal swing but that consumes even less power. The first circuit, which comprises selectable amplification elements, and the second circuit are coupled in parallel with selectable resistive elements and capacitive elements to provide varying amounts of amplification and filtering according to whether an operational mode is in a startup mode, a normal mode, or a low power mode of operation.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Michael Steven Kappes
  • Patent number: 7848778
    Abstract: A method and apparatus for using a conventional oscillator in a cellular telephone transceiver as a source of a reference signal for a GPS receiver. In one embodiment, the method comprises using a voltage-controlled oscillator (“VCXO”) within a cellular telephone transceiver to generate a reference frequency signal for the GPS receiver. Circuitry within the telephone transceiver generates a frequency error signal. Both of these signals are coupled to GPS circuitry and used to control a carrier numerically controlled oscillator (“NCO”) and a code NCO. The NCOs produce a tuning signal and a timing signal, respectively. The GPS circuitry uses the NCO generated signals to process GPS signals.
    Type: Grant
    Filed: August 16, 2006
    Date of Patent: December 7, 2010
    Assignee: Broadcom Corporation
    Inventor: Charles Abraham