Adaptive integrated hybrid with complex adaptation for digital subscriber line systems
Granted: December 31, 2013
Patent Number:
8619969
An adaptive hybrid system is coupled to a loop for adjusting trans-hybrid loss. The system comprises a fixed portion comprising a first receiver transfer function block and a first hybrid transfer function block. The fixed portion is configured to receive a far-end signal and mitigate frequency dependent attenuation experienced by the far-end signal. The system also comprises a variable portion comprising a second receiver transfer function block and a second hybrid transfer function…
Method and apparatus for DMT network data transfer
Granted: November 19, 2013
Patent Number:
8588052
A multi-tone modem has a plurality of shared and discrete components forming a transmit path and a receive path configured to couple to a wired communication medium for packet based communication thereon. The transmit path includes components for forming a communication packet including a hybrid preamble portion and a data portion. The hybrid preamble portion integrates both synch and timing info for packet alignment together with header information for determining at least packet…
Systems and methods for implementing a multi-sensor receiver in a DSM3 environment
Granted: November 5, 2013
Patent Number:
8576690
In accordance with one embodiment, a method is implemented in a vectored system for improving a signal-to-noise ratio (SNR) of a far end transmitted signal on a victim line in the system. The method comprises mitigating, by the vectored system, self-induced far-end crosstalk (self-FEXT) on the victim line based on self-FEXT mitigation coefficients and receiving, by a second sensor, information relating to at least one of: self-FEXT of the vectored system, external noise, and the far end…
Systems and methods for protecting DSL systems against impulse noise
Granted: October 8, 2013
Patent Number:
8555149
Systems and methods for protecting DSL systems against impulse noise are provided. Disclosed herein are example embodiments of a retransmission technique located above the gamma interface (i.e., in the network processing layer). Such a retransmission technique can be combined with standard RS coding with standard erasure-decoding & triangular interleaving at the PMS-TC layer. Example embodiments of the technique involve using the RS code to protect against REIN noise, and using…
Systems and methods for loop termination detection based on per-port calibration
Granted: August 20, 2013
Patent Number:
8515017
Systems and methods for performing loop termination are described. One embodiment is a method that comprises receiving a per-port calibrated echo signal of a loop under test, receiving a region designation and a loop length for the loop under test, and determining whether the loop is terminated by a short or open termination based on phase of the per-port calibrated echo signal.
Systems and methods for bridge tap detection based on per-port calibration
Granted: August 20, 2013
Patent Number:
8515016
Systems and methods for performing bridge tap detection are described. One embodiment is a method which comprises receiving an echo signal for a loop under test where the echo signal is a per-port calibrated echo response obtained using frequency domain reflectometry single-ended line testing (FDR-SELT). The method further comprises analyzing the echo signal to determine whether differentiating features are present in the per-port calibrated echo signal in order to determine whether the…
Method and apparatus for DSL communication over a 4 wire system
Granted: August 20, 2013
Patent Number:
8514917
A digital subscriber line ‘XDSL’ communication system for provisioning multi-tone modulated communications over two subscriber lines with two modems. The first modem has shared and discrete components forming a transmit path coupled exclusively to an end of a first of the two subscriber lines and a receive path coupled exclusively to an end of a second of the two subscriber lines. The second modem also has shared and discrete components forming a transmit path and a receive path…
Systems and methods for loop length estimation based on per-port calibration
Granted: August 13, 2013
Patent Number:
8509389
Systems and methods for performing loop length estimation are described. One embodiment includes a method which comprises receiving an echo signal for a loop under test where the echo signal is a per-port calibrated echo response obtained using frequency domain reflectometry single-ended line testing (FDR-SELT). The method further comprises analyzing characteristics of the echo signal to perform a loop length estimation based on data relating to ripple frequency as a function of loop…
Method and apparatus for forward error correction
Granted: July 30, 2013
Patent Number:
8498326
A multi-tone transceiver with a components forming a transmit path and a receive path configured to couple via a subscriber line to an opposing multi-tone transceiver for frequency division multiplexed multi-tone modulated communications therewith is disclosed. A noise margin channel identifier is configured to identify within a received tone set, discrete tones each associated with a corresponding one of at least two channels differing from one another in a relative noise margin of…
Transport frame structure for retransmission in DSL
Granted: June 11, 2013
Patent Number:
8463955
Included are embodiments for retransmission in a digital subscriber line environment. At least one embodiment of a method includes framing data into transport frames, each transport frame carrying payload data that is viewed differently according to the computing layer in which it is transported; transporting the transport frames over a first computing layer, the payload data of each transport frame corresponding to an integer number Q of elementary cells of the first computing layer, an…
Self-protection against non-stationary disturbances
Granted: June 4, 2013
Patent Number:
8457219
Included are embodiments for self protection. At least one embodiment includes Self-protection Unit for protecting a signal that includes a first receiving component configured to receive data, the received data being received as at least one frame and a subframing component configured to subframe at least a portion of the received data, wherein subframing includes converting the at least one into a plurality of subframes. Some embodiments include a subframe interleaver component…
Systems and methods for performing initial synchronization in wireless communications systems
Granted: May 21, 2013
Patent Number:
8446894
A method is described for performing frame synchronization that comprises performing a first synchronization to determine approximate timing of a frame boundary associated with a received signal. The method further comprises estimating frequency offset and symbol boundaries within the frame boundary based on the approximate timing and performing a second synchronization based on the frame boundary and the symbol boundary.
Method and apparatus for DMT crosstalk cancellation
Granted: April 23, 2013
Patent Number:
8427933
An apparatus for precoding multi-tone modulated transmissions of a plurality of communication channels over bundled subscriber lines. The apparatus includes a pseudo symbol controller and a precoder. The pseudo symbol controller detects a victim communication channel and an interferer communication channel having non-matching symbol rates, and transforms the interferor channel into a pseudo-symbol having both a substantially similar length as a corresponding symbol of the victim channel…
Hierarchical trellis coded modulation
Granted: April 9, 2013
Patent Number:
8418018
A system and method for encoding information is disclosed. In one embodiment, information is encoded using a high protection code for the least significant bit and a low protection code for the next three most significant bits. The remaining bits are uncoded. The high protection code may be a turbo code and the low protection code may be a trellis coded modulation code. In this embodiment, the collection of bits is then mapped according to a diagonally shifted QAM constellation…
Back channel communication
Granted: April 9, 2013
Patent Number:
8418004
Various embodiments are described for back channel communication. One embodiment is a method that comprises receiving data at customer premises equipment (CPE), determining at least one error in the received data, formatting the determined error for communication to a central office (CO), and sending the formatted error to the CO via a back channel, wherein the formatted error is sent between sync frames of a discrete multitone (DMT) superframe.
Retransmission above the gamma interface
Granted: April 2, 2013
Patent Number:
8413000
Embodiments disclosed herein are configured for retransmission above the gamma (?) interface. At least one embodiment of a method includes receiving data from an Ethernet layer, the data being identified as eligible for retransmission or not eligible for retransmission; in response to a determination that the data is eligible for retransmission, storing a copy of at least a portion of the data in a retransmission queue; and transmitting the data across a gamma (?) interface to a packet…
Systems and methods for impulse noise characterization
Granted: March 12, 2013
Patent Number:
8396688
Impulse noise from nearby or intense electrical sources can disrupt communications over digital subscriber lines (DSL). The characterization of the nature, timing and length of impulse noise sources present on a DSL loop is a critical first step in mitigating the effect of impulse noise on DSL communications. DSL standards provide histograms for impulse length and inter-arrival time of impulses. These histograms can be used to derive the nature, maximum frequency and other statistics…
Metric computation for lowering complexity of MIMO detection algorithms
Granted: March 5, 2013
Patent Number:
8391378
Included are embodiments of method for method for computing metrics. At least one embodiment includes searching a MIMO detection tree, the detection tree configuration being formed by a plurality of nodes and a plurality of leaves connected via a plurality of branches, the computational complexity associated with computing a node metric decreases with the node depth in the tree configuration and providing an estimate on a transmitted signal.
Reducing the effect of noise in a multi-channel telecommunication receiver
Granted: February 5, 2013
Patent Number:
8369426
A telecommunication receiver provided according to the present invention is implemented to receive a first signal containing information and noise on a first set of sensors and a second signal containing only noise on a second set of sensors. Receiver then decodes the information using first signal and second signal. In one embodiment, a bonded DSL receiver with k signals sensors is implemented with additional s number of noise only sensors to receive only noise. Accordingly, joint…
Crosstalk recognition in presence of radio frequency interference
Granted: January 8, 2013
Patent Number:
8351598
Crosstalk interference induced by the adjacent pairs is one of the major performance limiting factors of DSL systems. As there is a rapid increase in the deployment of DSL services worldwide, the need to provide information about noise related parameters to the operators and the service providers is of utmost importance. Satisfying such a need enables operators to anticipate the line capacity and understand the noise level characteristics of the loop environment. Specifically, crosstalk…
