Method and apparatus for DSL line card power management
Granted: January 1, 2013
Patent Number:
8345859
A XDSL line card including an allocator for allocating power to the multi-tone modulated communications on each of the subscriber lines, and for selecting control parameters sufficient to effect communications on each of the subscriber lines at a power level proximate to an allocated power level therefore. The line card also includes configurable components coupled to one another to form a transmit path and a receive path to couple to the digital subscriber lines. The configurable…
3-level line driver
Granted: January 1, 2013
Patent Number:
8344761
Included are embodiments of a 3-level line driver. At least one embodiment of a method includes generating a repetitive wave; receiving an input signal and a complement of the input signal; providing a 3-level output signal; and filtering a feedback signal, the means for filtering including at least one of the following: a 0th order filter, and an even order filter.
Method and apparatus for determining codeword interleaver parameters
Granted: December 18, 2012
Patent Number:
8335968
Modem selection of codeword interleaver parameters given standard based, operator based and channel based communication channel performance constraints. A processor implements processes for characterizing the forward error correction codeword and interleaver solution space in terms of expressions from which targeted portions of the solution space may be identified prior to evaluation of the magnitude of the coefficients of the corresponding nodes thereof for compliance with the to…
Method and apparatus for optimizing dynamic range in DMT modems
Granted: December 4, 2012
Patent Number:
8325825
A digital subscriber line ‘XDSL’ communication system for optimizing dynamic range in digital multi-tone modulated (DMT) modems. The system comprises a digital subscriber line access multiplexer (DSLAM) and at least one modem. The DSLAM distributes a near end crosstalk (NEXT) model of anticipated disturbance from neighboring disturber subscriber lines. The at least one modem has shared and discrete components forming a transmit path and a receive path. The at least one modem couples…
Systems and methods for characterizing loop termination via single-ended line testing
Granted: October 30, 2012
Patent Number:
8300771
Disclosed are various embodiments for determining a state of loop termination. One embodiment comprises receiving an un-calibrated echo signal for the loop under test using frequency domain reflectometry single-ended line testing (FDR-SELT) and determining the state of loop termination based on phase of the un-calibrated echo signal. The step of determining the state of loop termination comprises determining whether the loop is terminated by an open termination or a short termination by…
Cooperative MIMO for alien noise cancellation (COMAC) for upstream VDSL systems
Granted: October 30, 2012
Patent Number:
8300803
Included are embodiments for reducing alien crosstalk. At least one embodiment of a method includes receiving noise data associated with a first user signal on a first tone, receiving noise data associated with a second user signal on the first tone, and receiving at least one alien crosstalk canceller coefficient for the first user on the first tone. Some embodiments include applying the at least one alien crosstalk canceller coefficient to the second user signal to reduce alien…
Systems and methods for performing loop analysis based on un-calibrated single-ended line testing
Granted: October 23, 2012
Patent Number:
8295444
Systems and methods for performing loop analysis are described. Some embodiments are directed to determining loop characteristics such as loop gauge, loop termination, and straight-loop departure. One embodiment includes a method for performing loop length estimation which comprises receiving an un-calibrated echo signal for a loop under test using frequency domain reflectometry single-ended line testing (FDR-SELT), a region associated with the loop under test, and a platform type. The…
Systems and methods for performing combined equalization in communication systems
Granted: October 16, 2012
Patent Number:
8290033
A system is described for performing combined equalization. The system comprises a time domain equalizer (TEQ) configured to receive a signal and shorten a CIR (channel impulse response) of the received signal, a Fast Fourier Transform (FFT) module for demodulating the received signal, and an equalization block for reducing inter-carrier interference (ICI) and inter-symbol interference (ISI). The equalization block comprises at least one of: a feed forward equalizer and a feed back…
Adaptive turbo peak mitigation for peak-to-average ratio (PAR) reduction using reserved tones
Granted: September 25, 2012
Patent Number:
8275067
Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the…
Configurable impulse noise protection system and method based on impulse noise statistics
Granted: September 4, 2012
Patent Number:
8261149
Impulse noise from nearby or intense electrical sources can disrupt communications over digital subscriber lines. There are many methods to deal with errors produced by impulse noise sources. Forward error correction (FEC) codes such as Reed Solomon coding along with scrambling and interleaving are used to correct small errors. However, for larger errors, retransmission is favored. Retransmission can be applied at the Discrete Multi-tone symbol level thus eliminating the need to insert…
Method and apparatus for a multi-tone modem
Granted: July 17, 2012
Patent Number:
8223859
A multi-tone modem with shared and discrete components forming a transmit path and a receive path configured to couple to a wired communication medium to communicate at least one multi-tone modulated communication channel thereon. The modem includes a multi-tone modulator component and a configurable frequency up converter component. The multi-tone modulator component is configured for multi-tone modulation and demodulation of a transmitted and received communication channel at a base…
Low complexity systems and methods for peak-to-average ratio (PAR) reduction using reserved tones
Granted: July 3, 2012
Patent Number:
8213536
Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the…
Systems and methods for selecting tones for far-end cross talk mitigation
Granted: June 19, 2012
Patent Number:
8204211
Systems and methods are described for selecting tones for far-end crosstalk (FEXT) mitigation. In particular, systems and methods are described for performing far-end crosstalk (FEXT) mitigation within a digital subscriber line (xDSL) system. One embodiment is a method that comprises determining a first set of function values relating to a per-tone signal-to-noise ratio (SNR) for a user among a plurality of users for a number of tones, wherein the number of tones is less than or equal to…
Systems and methods for MIMO precoding in an xDSL system
Granted: June 5, 2012
Patent Number:
8194767
One embodiment is a method for precoding data for transmission in a discrete multi-tone (DMT) system to cancel self-induced far end crosstalk (self-FEXT). The method comprises learning, by the system, characteristics associated with a plurality of N users within a digital subscriber line (xDSL) system to determine an initial off-diagonal multiple input multiple output (MIMO) precoder (ODMP) for a given tone frequency and converging towards an ODMP from the initial ODMP to cancel…
Method and apparatus for data transmission in home networks
Granted: May 29, 2012
Patent Number:
8189457
A multi-tone modem with components forming a transmit path and a receive path configured to couple to a wired communication medium for at least intermittent communication of frequency division multiplexed multi-tone modulated communication channels thereon. A Fourier transform component transforms received communication channels between a time domain and a frequency domain and vice-versa. Selected components on the receive path determine alignments between the received multiplexed…
Systems and methods for mitigating impulse noise
Granted: February 7, 2012
Patent Number:
8112687
Various embodiments for mitigating impulse noise are disclosed that cooperatively use impulse noise statistics to utilize retransmission, forward error correction (FEC), and blanking to mitigate the effects of a wide variety of impulse noise sources.
Systems and methods for performing SISO detection in a WiMAX environment
Granted: January 24, 2012
Patent Number:
8102946
In accordance with some embodiments, a communication system is described that comprises a soft-output detector configured to receive a transmit signal and output reliability information regarding the received signal. In accordance with such embodiments, the detector comprises a symbol combiner configured to operate in both a repetition mode and a non-repetition mode, wherein repetition mode comprises receiving a plurality of signals for the transmit signal.
Method and apparatus for a multi-protocol XDSL line driver
Granted: October 11, 2011
Patent Number:
8036293
A transceiver having shared and discrete components forming a transmit path and a receive path configured to couple to a communication medium for establishing a multi-tone modulated communication channel thereon. The transceiver includes a line driver component on the transmit path. The line driver is configured to respond to a protocol determination and by configuring at least one of a transmit power level and a transmit bandwidth of the multi-tone modulated communication channel on the…
Configuring transmission signals
Granted: October 4, 2011
Patent Number:
8031759
Included are embodiments for reducing interference in a communications network. At least one embodiment of a method includes receiving data related to an updated Power Spectral Density (PSD) mask and processing a first Seamless Rate Adaptation (SRA) request. Some embodiments include processing a second Seamless Rate Adaptation request and implementing the updated Power Spectral Density mask.
Subframe interleaving
Granted: October 4, 2011
Patent Number:
8032800
Included are embodiments for subframe interleaving. At least one embodiment of a method includes receiving at least one subframe, the at least one subframe being derived from a plurality of frames of data and interspersing at least a portion of the at least one subframe according to a predetermined subframe interleaving strategy.
