Patents Assigned to Broadcom Corporation
  • Publication number: 20070044001
    Abstract: Single stage implementation of min*, max*, min and/or max to perform state metric calculation in soft-in soft-out (SISO) decoder. This allows for calculation of state metrics in an extremely efficient, fast manner. When performing min or max calculations, comparisons are made using 2 element combinations of the available inputs. Subsequently, logic circuitry employs the results of the 2 element comparisons the smallest (min) or largest (max) input. The max or min implementations may be employed as part of the max* and/or min* implementations. For max* and/or min* implementations, simultaneous calculation of appropriate values is performed while determining which input is the smallest or largest. Thereafter, the determination of which input is the smallest or largest is used to select the appropriate resultant value (of the values calculated) for max* and/or min*. Various degrees of precision are employed for the log correction values within the max* and/or min* implementations.
    Type: Application
    Filed: October 5, 2006
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation, a California Corporation
    Inventors: Kelly Cameron, Thomas Hughes, Hau Tran
  • Publication number: 20070041246
    Abstract: A one-time programmable device includes a controller, a protection system, a static storage element and a latch, which can be referred to as a latch-based one-time programmable (OTP) element. In one example, the static storage element includes a thin gate-oxide that acts as a resistance element, which, depending on whether its blown, sets the latch into one of two states.
    Type: Application
    Filed: October 30, 2006
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation
    Inventors: Douglas Smith, Myron Buer, Bassem Radieddine
  • Publication number: 20070040267
    Abstract: Methods, systems, and apparatuses for attaching heat sinks to integrated circuit packages using thermally conductive adhesive materials are described. The adhesive materials can be shaped to conform to surfaces of the integrated circuit package and/or heat sink, prior to hardening, such as by curing the adhesive material.
    Type: Application
    Filed: October 31, 2005
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation
    Inventors: Sam Zhao, Reza-ur Khan
  • Publication number: 20070040713
    Abstract: A low-complexity sampling rate conversion (SRC) method and apparatus for the processing of digital audio signals. A first stage upsamples an input audio signal to generate an upsampled audio signal. For example, the first stage may perform 1:2 upsampling using a halfband filter. A second stage re-samples the upsampled audio signal from the first stage at a target sampling rate. For example, re-sampling may be achieved using linear interpolation.
    Type: Application
    Filed: October 26, 2006
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation
    Inventor: Juin-Hwey Chen
  • Publication number: 20070044000
    Abstract: Variable modulation within combined LDPC (Low Density Parity Check) coding and modulation coding systems. A novel approach is presented for variable modulation encoding of LDPC coded symbols. In addition, LDPC encoding, that generates an LDPC variable code rate signal, may also be performed as well. The encoding can generate an LDPC variable code rate and/or modulation signal whose code rate and/or modulation may vary as frequently as on a symbol by symbol basis. Some embodiments employ a common constellation shape for all of the symbols of the signal sequence, yet individual symbols may be mapped according different mappings of the commonly shaped constellation; such an embodiment may be viewed as generating a LDPC variable mapped signal. In general, any one or more of the code rate, constellation shape, or mapping of the individual symbols of a signal sequence may vary as frequently as on a symbol by symbol basis.
    Type: Application
    Filed: October 3, 2006
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation, a California Corporation
    Inventors: Ba-Zhong Shen, Hau Tran, Kelly Cameron
  • Publication number: 20070040593
    Abstract: The present invention relates to frequency dividers. The frequency divider comprises an input, a counter, a first comparator, an interconnect, and an output. The counter has a counter reset port and is configured to receive a clock signal from the input and to produce a sum signal. The first comparator is configured to receive the sum signal, to compare the sum signal to a first integer, and to produce a first comparison signal. The interconnect is configured to convey the first comparison signal from the first comparator to the counter reset port. The output coupled to the first comparator. The clock signal has a periodic waveform. The sum signal represents a first sum, which equals a number of waveforms of the clock signal received by the counter after the counter has been reset. In a first embodiment, the first integer is selectable from a set of at least three consecutive integers. In a second embodiment, a frequency of the clock signal is at least 1.5 gigahertz.
    Type: Application
    Filed: February 9, 2006
    Publication date: February 22, 2007
    Applicant: Broadcom Corporation
    Inventors: Karapet Khanoyan, Mark Chambers
  • Patent number: 7180892
    Abstract: A signal processing system which discriminates between voice signals and data signals modulated by a voiceband carrier. The signal processing system includes a voice exchange, a data exchange and a call discriminator. The voice exchange is capable of exchanging voice signals between a switched circuit network and a packet based network. The signal processing system also includes a data exchange capable of exchanging data signals modulated by a voiceband carrier on the switched circuit network with unmodulated data signal packets on the packet based network. The data exchange is performed by demodulating data signals from the switched circuit network for transmission on the packet based network, and modulating data signal packets from the packet based network for transmission on the switched circuit network. The call discriminator is used to selectively enable the voice exchange and data exchange.
    Type: Grant
    Filed: September 1, 2000
    Date of Patent: February 20, 2007
    Assignee: Broadcom Corporation
    Inventor: Onur Tackin
  • Patent number: 7180951
    Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions multi-transmitter system for unshielded twisted pair (UTP) data communication applications. For each transmitter, digital transmit data is converted to a current-mode differential signal analog waveform by a digital-to-analog converter (DAC). The output current from each DAC is used to generate the required transmit voltage on the respective UTP line. Timing circuitry staggers the time base of each transmitter to reduce the aggregate EMI emissions of the multi-transmitter system.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: February 20, 2007
    Assignee: Broadcom Corporation
    Inventor: Kevin T. Chan
  • Patent number: 7178992
    Abstract: The present invention includes an optical transceiver having a fiber module with an optical data input and an electrical data output. The fiber module further includes a signal detect output that indicates the receipt of valid optical data. A physical layer device having a receive input is coupled to the electrical data output through a switch that is controlled by the signal detect output. The switch passes electrical data from the electrical data output of the fiber module to the receive input when the signal detect output indicates the receipt of valid optical data, and does not pass the electrical data when the signal detect output indicates invalid optical data. By using this configuration, the signal detects pins of the physical layer device are eliminated. In another embodiment, the switch is not utilized, and the electrical data output of the transceiver is ac-coupled to the differential receive input of the physical layer device.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: February 20, 2007
    Assignee: Broadcom Corporation
    Inventors: Todd Vafiades, Art Pharn
  • Patent number: 7181187
    Abstract: A radio frequency transmitter includes a digital baseband and coding module, an inverse fast Fourier transform (IFFT) module, a complex digital filter, a complex digital-to-analog converter and a radio frequency modulation module. The digital baseband and coding module is operably coupled to convert outbound data into outbound symbols in accordance with a baseband encoding protocol. The IFFT module is operably coupled to convert the outbound symbols into a complex time domain sample sequence. The complex digital filter is operably coupled to filter the complex time domain sequence such that signal strength of outbound RF signals in an exclusion RF band is at or below a specified signal strength with negligible attenuation on in-band signal strength.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: February 20, 2007
    Assignee: Broadcom Corporation
    Inventors: Jason A. Trachewsky, Alan Corry
  • Patent number: 7180435
    Abstract: A low-complexity sampling rate conversion (SRC) method and apparatus for the processing of digital audio signals. A first stage upsamples an input audio signal to generate an upsampled audio signal. For example, the first stage may perform 1:2 upsampling using a halfband filter. A second stage re-samples the upsampled audio signal from the first stage at a target sampling rate. For example, re-sampling may be achieved using linear interpolation.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: February 20, 2007
    Assignee: Broadcom Corporation
    Inventor: Juin-Hwey Chen
  • Publication number: 20070038749
    Abstract: A method, system and computer program product for a generic data storage interface for local and remote networked storage is provided. It comprises providing a data storage interface accessible by an operating system, transmitting data from an application running on the operating system to the data storage interface and selectively storing the data using the same data storage interface in either a local or a remote networked storage location.
    Type: Application
    Filed: October 28, 2005
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation
    Inventors: Eric Noya, Chris Franklin, Randy Arnott, Jeffrey Wong
  • Publication number: 20070037531
    Abstract: A downstream adaptive modulation system and method. The downstream adaptive modulation system comprises a wireless access termination system and one or more wireless modems. The wireless access termination system includes a plurality of queues and a parser. The parser parses data traffic onto the plurality of queues. Each queue is associated with a different coding and modulation scheme. Each of the one or more wireless modems receives data traffic from the plurality of queues based on the wireless modem's ability to demodulate and decode the signal from each of the plurality of queues. When a wireless modem experiences a change in signal strength, the present invention enables the wireless modem to adapt to data from other queues to compensate for the change in signal strength. Thus, if the signal strength improves over a period of time, the wireless modem may receive data at a higher order modulation and FEC code rate.
    Type: Application
    Filed: October 19, 2006
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation
    Inventors: Mark Dale, David Hartman, Anders Hebsgaard
  • Publication number: 20070036170
    Abstract: A method for collision avoidance in multiple protocol networks using a shared communication medium begins by determining a first protocol probable active time period. The method continues by determining a first protocol probable inactive time period. The method continues by generating a transmit blocking indication based on the first protocol probable active time period and the first protocol probable inactive time period.
    Type: Application
    Filed: October 10, 2006
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation, a California Corporation
    Inventors: Mark Gonikberg, Matthew Fischer, Manoj George
  • Publication number: 20070036246
    Abstract: Methods and systems for reconfigurable soft-output bit demapping, reconfigurable for different modes of operation (i.e., different transmitter/receiver configurations) and for different modulation schemes are provided. In an embodiment, a reconfigurable soft-output bit demapping system includes a mode/modulation independent equalizer, a plurality of mode/modulation independent soft-slicers coupled to the outputs of the equalizer, a plurality of mode/modulation independent post-scalers coupled to the outputs of the soft-slicers, and a mode-dependent coefficient calculator. The coefficient calculator generates parameters for configuring the equalizer, the soft-slicers, and the post-scalers according to the used mode of operation and modulation scheme.
    Type: Application
    Filed: August 8, 2006
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation
    Inventor: Joachim Hammerschmidt
  • Publication number: 20070036245
    Abstract: Methods and systems for reconfigurable soft-output bit demapping, reconfigurable for different modes of operation (i.e., different transmitter/receiver configurations) and for different modulation schemes are provided. In an embodiment, a reconfigurable soft-output bit demapping system includes a mode/modulation independent equalizer, a plurality of mode/modulation independent soft-slicers coupled to the outputs of the equalizer, a plurality of mode/modulation independent post-scalers coupled to the outputs of the soft-slicers, and a mode-dependent coefficient calculator. The coefficient calculator generates parameters for configuring the equalizer, the soft-slicers, and the post-scalers according to the used mode of operation and modulation scheme.
    Type: Application
    Filed: August 4, 2006
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation
    Inventor: Joachim Hammerschmidt
  • Publication number: 20070036176
    Abstract: A number of features for enhancing the performance of a communication system, in which data is transmitted between a base station and a plurality of subscriber stations located different distances from the base station, are presented. The power transmission level, slot timing, and equalization of the subscriber stations are set by a ranging process. Data is transmitted by the subscriber stations in fragmented form. Various measures are taken to make transmission from the subscriber stations robust. The uplink data transmission is controlled to permit multiple access from the subscriber stations.
    Type: Application
    Filed: October 23, 2006
    Publication date: February 15, 2007
    Applicant: Broadcom Corporation
    Inventors: Thomas Quigley, Jonathan Min, Lisa Denney, Henry Samueli, Sean Nazareth, Feng Chen, Fang Lu, Christopher Jones
  • Patent number: 7177353
    Abstract: A method for providing a next-cycle input sample from a decision feedback equalizer to a symbol decoder using look-ahead computations such that timing contention between the decision feedback equalizer and the symbol decoder is reduced. During a symbol period, a set of possible values is computed in the decision feedback equalizer and a set of path memory symbols is computed in the symbol decoder, the set of path memory symbols being based on a current input sample. During the same symbol period, one of the possible values is selected as the next-cycle input sample based on at least one of the next-cycle path memory symbols produced from the symbol decoder.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: February 13, 2007
    Assignee: Broadcom Corporation
    Inventors: Arthur Abnous, Avanindra Madisetti, Christian A. J. Lutkemeyer
  • Patent number: 7177374
    Abstract: A method is described for correcting sampling frequency offset (SFO) of a data packet in a communications system where carrier frequency (fc) and sampling frequency (fs) are driven by a common clock source. The method comprises, for each lth symbol in the data packet, estimating carrier frequency offset (CFO) in a received data packet. From the CFO estimate, an SFO estimate is derived, wherein the SFO is approximately equal to fs multiplied by said CFO estimate, and divided by fc. An SFO phase correction is generated according to the SFO estimate for each kth tone in a data stream. The SFO phase correction is then applied to each received data stream.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: February 13, 2007
    Assignee: Broadcom Corporation
    Inventors: Rohit V. Gaikwad, Rajendra T. Moorti
  • Patent number: 7177986
    Abstract: A cache is configured to receive direct access transactions. Each direct access transaction explicitly specifies a cache storage entry to be accessed in response to the transaction. The cache may access the cache storage entry (bypassing the normal tag comparisons and hit determination used for memory transactions) and either read the data from the cache storage entry (for read transactions) or write data from the transaction to the cache storage entry (for write transactions). The direct access transactions may, for example, be used to perform testing of the cache memory. As another example, direct access transactions may be used to perform a reset of the cache (by writing known data to each cache entry). In embodiments employing error checking and correction (ECC) mechanisms, direct access write transactions could also be used to recover from uncorrectable ECC errors, by overwriting the failing data to eliminate the errant data.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: February 13, 2007
    Assignee: Broadcom Corporation
    Inventors: Joseph B. Rowlands, Michael P. Dickman