Patents Assigned to Conexant System, Inc.
  • Publication number: 20090245340
    Abstract: The measurement of far-end crosstalk (FEXT) in a Digital Subscriber Line communications is instrumental in the ability of using a multiple input multiple output (MIMO) pre-coder to cancel FEXT. A reliable robust back channel for transmission of error is instrumental to provide error samples for the proper operation of a MIMO pre-coder. Bins can be dedicated to insure bandwidth from the customer premises equipment (CPE) to the central office (CO). By increasing the margin used in the bins, robustness can be added to this back channel between the CPE and CO.
    Type: Application
    Filed: March 26, 2009
    Publication date: October 1, 2009
    Applicant: Conexant Systems, Inc.
    Inventors: Massimo Sorbara, Patrick Duvaut, Amitkumar Mahadevan, Laurent Francis Alloin
  • Patent number: 7590674
    Abstract: Presently disclosed is method and apparatus for generating a random bit stream by generating a random bit according to a polynomial expression, providing a modification function operative on the polynomial expression, and modifying the polynomial expression by modifying the modification function.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: September 15, 2009
    Assignee: Conexant Systems, Inc.
    Inventor: Mark E. Miller
  • Patent number: 7590248
    Abstract: A method for generating a head related transfer function comprises downconverting each of a plurality of measured impulse responses from a first sampling frequency to a second sampling frequency and then converting each downconverted impulse responses to a set of head related transfer functions. Coordinate conversion can then be performed on each set of head related transfer functions. The converted sets of head related transfer functions are then averaged to generate one average head related transfer function. The average head related transfer function can be decimated to fit a filter engine of a target system.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: September 15, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Paul Chen, Harry Lau
  • Patent number: 7590163
    Abstract: There is provided a method of modifying a first clock to generate a second clock with reduced electromagnetic interference (EMI). The method comprises receiving the first clock, generating an upslew modulation form during an upslew frequency transition, generating a downslew modulation form during a downslew frequency transition, modulating a frequency of the first clock over a period of time using the upslew modulation form and the downslew modulation form to generate the second clock, and wherein the upslew modulation form and the downslew modulation form are different. The upslew modulation form and the downslew modulation form are defined by upslew modulation values and downslew modulation values, respectively, and the method further comprises receiving the upslew modulation values and the downslew modulation values, and generating fractional upslew modulation values and fractional downslew modulation, respectively, for modulating the frequency of the first clock.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: September 15, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Mark Miller, Chilan T. Nguyen
  • Patent number: 7586644
    Abstract: A processor is provided that includes a primary memory of a processor and color conversion logic. The primary memory is to store a first color look-up table (LUT) related to a second color space. The color conversion logic is responsive to a received set of pixels, where each pixel of the set of pixels includes a color value in a first color space. The color conversion logic includes decision logic to selectively access the first color LUT and a second color LUT of a secondary memory to obtain a color value of the second color space that is associated with each pixel of the set of pixels based on a comparison of each pixel to at least one neighboring pixel.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: September 8, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Derek T. Walton, John J. Koger
  • Patent number: 7564932
    Abstract: Systems and methods for achieving a maximum bit rate in a Discrete MultiTone (DMT) system using a quad spectrum under constraints of avoiding interference with radio frequency interference (RFI) are described. At least one embodiment utilizes bins in notched areas for transmission over short loops without violating the power spectral density (PSD) mask in order to optimize bit allocation.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: July 21, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Ehud Barak, Albert Rapaport
  • Patent number: 7564928
    Abstract: A system and method for designing a broadband tuner such that VCO pulling is minimized and gaps in frequency coverage are avoided, while total power consumption is reduced, is disclosed. A broadband spectrum is divided into sub-bands and various multipliers to a local oscillator output are introduced. In this fashion, the present invention allows a local oscillator within the broadband tuner to always generate signals that lie outside of the broadband spectrum for a particular broadband application. Additionally, a modulus ratio for a dual modulus prescaler with the local oscillator is maximized, thereby reducing power consumption.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: July 21, 2009
    Assignee: Conexant Systems, Inc.
    Inventor: Arun Jayaraman
  • Patent number: 7555052
    Abstract: Method and System for evaluating a turbo-coding scheme suitable for VDSL2 systems. The scheme is a Turbo-Trellis Coded Modulation TTCM that makes use of a Parallel Concatenated Convolutional Code (PCCC) including an inner Latin square/rectangular matrix of Random sequence pattern Interleaver (LRI) of approximately 2044 bits. In the presence of the outer Reed Solomon Code but without an outer interleaver (fast mode), the method and system provides 7.1 dB of average net coding gain, i.e., 2.6 dB of coding gain improvement relative to the standard 16 states 4-dimensional (4-D) trellis code used in current ADSL2 systems. The substantial coding gain achieved through the method and system, leads to an increase in the VDSL2 rate by 38% at 6 kft against local exchange carriers, such as ILEC (SBC) conditions with approximately 1.5 ms of latency. By encoding only two bits per tone (i.e., 1 bit per dimension), the turbo code implementation complexity is kept reasonable.
    Type: Grant
    Filed: October 13, 2005
    Date of Patent: June 30, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Julien Pons, Patrick Duvaut
  • Patent number: 7535606
    Abstract: A method of directly obtaining a Y value for a luminance/chrominance representation of a scanline of a color scanned image produced by a color contact image sensor device having a linear sensor array to collect reflected light, wherein said contact image sensor device comprises red, green and blue light sources and wherein an optimal on time for each of the light sources is calibrated, the method comprising the step of illuminating the scanline during a single pulse independently with the red, the green and the blue light sources and allowing the linear sensor array to accumulate the reflected light from all of the light sources.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: May 19, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Derek T. Walton, Brendan P. Mullaly
  • Patent number: 7532670
    Abstract: In one aspect, a method for encoding pictures is provided. The method is applied to each picture in a sequence of pictures, and the method comprises the steps of assigning a pre-decoder buffer removal time to the picture; selecting, for the picture, a number of bits, wherein the time-equivalent of the number of bits is no greater than a difference based on the pre-decoder buffer removal time of the picture and an initial arrival time of the picture into a pre-decoder buffer; and compressing the picture to generate the number of bits. The method may further include the step of allocating a first number of bits for compressing the picture and one or more number of bits for compressing one or more future pictures, wherein the future pictures are in the pre-decoder buffer at the pre-decoder buffer removal time of the current picture.
    Type: Grant
    Filed: September 5, 2003
    Date of Patent: May 12, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Eric Viscito, Dzung T. Hoang
  • Publication number: 20090086733
    Abstract: A two-chip/single-die switch architecture and a method for accessing a DDR SDRAM memory store in a switching environment are presented. The two-chip/single-die architecture includes an internal memory storage block on the single-die, an external memory storage interface to a Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM), an external memory manager, and a packet data transfer engine effecting packet data transfers between an internal memory store and the external DDR SDRAM memory. The packet data transfer engine operates as an adaptation layer addressing issues related to employing appropriate: addressing schemes, granule sizes, memory transfer burst sizes, access timing, etc. The packet data transfer engine includes a minimal number of dual mode operational blocks such as: a queue manager, and adaptation receive and transmit blocks.
    Type: Application
    Filed: December 4, 2008
    Publication date: April 2, 2009
    Applicant: Conexant Systems, Inc.
    Inventors: Craig Barrack, Yeong Wang, Rong-Feng Chang
  • Patent number: 7489693
    Abstract: Automatic detection of the virtual circuit setting and encapsulation type of a DSL line. A DSL modem determines the correct virtual path identifier (VPI) and virtual channel identifier (VCI) by sending OAM loopback requests to different VPI/VCI pairs until a valid loopback reply is received. PPPoA encapsulation is detected when a valid reply is received to a PPP LCP configuration request or echo request. PPPoE encapsulation is detected when a valid reply is received to a PPP LCP termination request or a PPPoE discovery offer (a PADO packet) is received in response to a PPPoE discovery initiation request (a PADI packet).
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: February 10, 2009
    Assignee: Conexant Systems, Inc.
    Inventor: Haibo Xu
  • Patent number: 7486688
    Abstract: A two-chip/single-die switch architecture and a method for accessing a DDR SDRAM memory store in a switching environment are presented. The two-chip/single-die architecture includes an internal memory storage block on the single-die, an external memory storage interface to a Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM), an external memory manager, and a packet data transfer engine effecting packet data transfers between an internal memory store and the external DDR SDRAM memory. The packet data transfer engine operates as an adaptation layer addressing issues related to employing appropriate: addressing schemes, granule sizes, memory transfer burst sizes, access timing, etc. The packet data transfer engine includes a minimal number of dual mode operational blocks such as: a queue manager, and adaptation receive and transmit blocks.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: February 3, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Craig Barrack, Yeong Wang, Rong-Feng Chang
  • Patent number: 7484070
    Abstract: A memory of allocating memory for use by a subfunction of a computer chip, wherein the subfunction uses contiguous memory regions, the method comprising the steps of (a) creating a placeholder for contiguous memory buffers used by the subfunction of the chip by reserving a region of memory subsystem space, wherein the region does not need to be backed by true physical storage and the size is at least as large as the contiguous memory buffer required by the subfunction, (b) allocating pages of remaining memory in the memory subsystem to satisfy the amount of memory required by the subfunction, wherein the allocated pages do not necessarily result in a contiguous memory region, (c) remapping the allocated pages of step b into a contiguous region of the placeholder created in step a and (d) disabling the remapping after the subfunction is completed to free the memory in the placeholder.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: January 27, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Derek T. Walton, Carl M. Mikkelsen
  • Patent number: 7474357
    Abstract: Provided are decoding methods and decoders for separating luminance and chrominance components of a video signal. In one aspect, a reference subcarrier of a first line of the video signal is used for subsequent lines by applying an appropriate rotation to the reference subcarrier of the first line for each subsequent line. In another aspect, comb filtering is adaptively controlled based on determining whether 90 or 180 degrees relationship is maintained from line to line. In a further aspect, both complimentary and non-complimentary comb filtering are implemented. In yet another aspect, SECAM bell filtering is achieved by rotating the video signal to obtain a baseband signal, low-pass filtering and modulating the baseband signal, and subtracting the modulated low-pass filtered baseband signal from the video signal to notch the chroma component from the luma component.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: January 6, 2009
    Assignee: Conexant Systems, Inc.
    Inventors: Peter M. Murdock, John E. Welch
  • Patent number: 7466758
    Abstract: The present invention provides a method and apparatus for a new interleaver adaptation scheme that achieves “error free” and zero delay (interleaving—triangular) or near zero delay variation (interleaving—GCI), and with easier implementation but no additional memory required. The dummy insertion methods and systems embodiments of the invention provide an effective dummy byte insertion scheme for applications that require seamless on-line rate changes, e.g., SRA (seamless rate adaptation), DRR (dynamic rate repartitioning) and adaptive INP (impulse noise protection).
    Type: Grant
    Filed: December 9, 2005
    Date of Patent: December 16, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Tao Xue, Massimo Sorbara, Ho-Ming Lin
  • Patent number: 7460649
    Abstract: A method and apparatus for single end loop testing for DSL provisioning and maintenance provides testing of the DSL loop using digital techniques including frequency compensation, matched filtering and median filtering, to remove strong background and enhance desired signal for peak detection. The SELT system allows DSL providers to extract loop information from reflective measurements at the central office (CO) so as to determine loop capability of supporting different DSL services. The method and apparatus acquires the desired signal (the far-end echo) which is submerged in the correlated background noise (the near-end echo) by providing a process for detecting loop length and termination types with high accuracy for loops up to 12 kft for 24 AWG and up to 9 kft for 26 AWG by exploiting several digital signal processing techniques including frequency.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: December 2, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Feng Ouyang, Patrick Duvaut, Ming Gu
  • Patent number: 7453600
    Abstract: There is provided a method for enhancing text reproduction by a color copier in a copy of a document that includes both text and graphic regions, the method includes creating an ink density map from a data image of the document identifying a region of the ink density map as a text region, a partial text region, a color region or a white region and modifying the data image for corresponding regions identified as text areas.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: November 18, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Derek T. Walton, Gyung Nam Boo
  • Patent number: 7450604
    Abstract: Local area network bandwidth is partitioned into periodic data frames. Data frames are further segregated into spectrum and time slots. Bandwidth reserved by assigning spectrum and time slots to particular circuit connections; enabling deterministic data transfer from source to destination nodes. Bandwidth reservations are broadcast to nodes attached to network.
    Type: Grant
    Filed: April 21, 2003
    Date of Patent: November 11, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Steven H. Gardner, James E. Petranovich
  • Patent number: 7447375
    Abstract: A method of compensating for image intensity variation in a scanline of a scanned image caused by variation in sensor integration time in a non-shuttered CCD image sensor comprising the steps of (a) determining for the scanline a multiplicative compensation factor, Kc (b) multiplying the sensed intensity of light received by sensor elements present in the CCD image sensor for the scanline by Kc to produce a compensated intensity value for the scanline and (c) employing the compensated intensity value in an image processing pipeline to produce the scanned image.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: November 4, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Derek T. Walton, Brendan P. Mullaly