Abstract: The present invention relates generally to addressing performance issues in xDSL communication systems, and more particularly to methods and apparatuses to measure and characterize CM noise impacting a DSL line in a customer premises, measurements and characterization of the projection of these CM signals in Differential Mode (DM), and finally a derivation of an estimate of the loop balance.

Abstract: The present invention relates generally to addressing performance issues in xDSL communication systems, and more particularly to methods and apparatuses to measure and characterize CM noise impacting a DSL line in a customer premises, measurements and characterization of the projection of these CM signals in Differential Mode (DM), and finally a derivation of an estimate of the loop balance.

Abstract: The present invention relates generally to addressing performance issues in xDSL communication systems, and more particularly to methods and apparatuses to measure and characterize CM noise impacting a DSL line in a customer premises, measurements and characterization of the projection of these CM signals in Differential Mode (DM), and finally a derivation of an estimate of the loop balance.

Abstract: Embodiments of the invention relate to methods and apparatuses for performing hybrid rejection that overcome various shortcomings of the prior art. In one embodiment, the transformer's receive winding is stacked on top of the transmit winding, the two being wired in series and in phase. Z2 is scaled by approximately half so as to maintain the same receive gain. In another embodiment, rather than stacking the receive and transmit windings for series summation, they are each used as independent sources into the summing junction of the receive amp. If Z2 and Z3 are equal, then an equal proportion of V1 and V2 are summed.

Abstract: The present invention relates generally to addressing performance issues in xDSL communication systems, and more particularly to methods and apparatuses to measure and characterize CM noise impacting a DSL line in a customer premises, measurements and characterization of the projection of these CM signals in Differential Mode (DM), and finally a derivation of an estimate of the loop balance.

Abstract: A method and apparatus to generate a common-mode reference signal. A common-mode current is received at a common-mode current sensing circuit. The common-mode current is sampled at a node between the common-mode current sensing circuit and a shunt resistor. The resulting voltage across the shunt resistor from the applied common-mode current is used as a common-mode reference signal.

Abstract: A method, apparatus, and system in which one embodiment includes a network interface device (NID) located outside a building and a power supply unit located inside the building. The power supply unit has an electrical isolation component and one or more ports that couple via a first phone line and a second phone line to the NID to provide isolated DC power to the NID.

Abstract: A method and apparatus to generate a common-mode reference signal. A common-mode current is received at a common-mode current sensing circuit. The common-mode current is sampled at a node between the common-mode current sensing circuit and a shunt resistor. The resulting voltage across the shunt resistor from the applied common-mode current is used as a common-mode reference signal.

Abstract: Various methods, apparatuses, and systems in which a back up power supply is provided to a network interface device are described. In one embodiment, an apparatus includes a network interface device (NID) located outside a building and a power supply unit located inside the building. The power supply unit has one or more ports that couple via a phone line to the NID to provide a power signal to the NID. The apparatus further includes a direct current (DC) back up power unit located in the NID. The DC back up power unit provides back up power to the NID. The NID is configured to periodically switch between receiving the power signal from the power supply unit and the DC back up power unit even when no fault condition exists in the power supply unit.

Abstract: Methods and apparatuses for reducing effects of impulse noise in a DSL transmitter receiver device are described. According to certain embodiment, the method includes using a periodicity associated with the impulse noise affecting a DSL transmitter receiver device to determine data frames that are affected by the impulse noise, and sending a reduced data rate during those frames. In certain embodiments, no data is sent during those frames. The method further includes using a high margin bits and gain table, instead of a normal bits and gain table.

Abstract: In an embodiment, a DSL communication device comprising a line interface circuit is disclosed. The line interface circuit includes a hybrid circuit to interface the communication device to a communication line, a lowpass transmit filter to pass signals in a first frequency band, and a highpass transmit filter to pass signals in a second frequency band, where the second frequency band is higher in frequency than the first frequency band. The outputs of the highpass and lowpass filters are coupled in parallel to the communication line. The lowpass and highpass filters as well as the low and highpass transformers are optimized for their frequency bands. Further, the edges of the low and high frequency bands are sufficiently separated to reduce interference from the other frequency band. These factors, in part, allow a multiple tone communication device to be capable of operating in multiple modes of operation with multiple DSL varieties.

Abstract: A method and apparatus to simulate a length of telecommunications line. One or more bi-directional constant input impedance low pass or pole/zero filters are coupled in series with an attenuator to simulate a length of telecommunications line. The one or more filters are used to approximate the transfer function of the length of telecommunications line.

Abstract: A method and apparatus to generate a common-mode reference signal. A common-mode current is received at a common-mode current sensing circuit. The common-mode current is sampled at a node between the common-mode current sensing circuit and a shunt resistor. The resulting voltage across the shunt resistor from the applied common-mode current is used as a common-mode reference signal.

Abstract: A line interface circuit with line side cancellation of a communication device is described herein. In one embodiment, a communication device includes a line interface circuit for interfacing a communication line. The line interface circuit includes a driver for driving multiple transmitting signals onto the communication line over multiple transmitting frequency bands. The line interface circuit further includes multiple transmitting filters each corresponding to one of the transmitting frequency bands. Other methods and apparatuses are also described.

Abstract: Various methods, apparatuses, and systems in which a residential gateway is located at the network interface device and is powered with a remote power source inside the residence. In another embodiment, bi-directional data communication between the residential gateway and the remote power source is also enabled.

Abstract: In general, various methods, apparatuses, and systems for a surge protection circuit for a Public Switched Telephone Network (PSTN) are disclosed. The surge protection circuit includes a first voltage protection device coupled to a first wire of the PSTN. A voltage protection device conducts when voltage applied across the voltage protection device at least meets a set voltage threshold. The surge protection circuit includes a second voltage protection device coupled to a second wire of the PSTN. The second voltage protection device is coupled to the first voltage protection device in series. The surge protection circuit includes a voltage divider device to cause a voltage applied differentially across the first wire and second wire to divide evenly across the first voltage protection device and the second voltage protection device.

Abstract: Various methods, apparatuses, and systems are described in which devices having no common electrical ground communicate. In at least certain embodiments, an apparatus includes a transformer block to communicate a plurality of data signals and a synchronous clock signal between a first device with a first ground reference and a second device with a second ground reference over a data communication link. The first device sends the plurality of data signals to a modulator block having one or more Boolean logic gates that receive each data signal in combination with the synchronous clock signal. The modulator block sends a plurality of modulated data signals corresponding to the plurality of data signals to the transformer block. The transformer block sends the plurality of modulated data signals and the synchronous clock signal to the second device to provide the data communication link between devices having different ground references.

Abstract: In an embodiment, a DSL communication device comprising a line interface circuit is disclosed. The line interface circuit includes a hybrid circuit to interface the communication device to a communication line, a lowpass transmit filter to pass signals in a first frequency band, and a highpass transmit filter to pass signals in a second frequency band, where the second frequency band is higher in frequency than the first frequency band. The outputs of the highpass and lowpass filters are coupled in parallel to the communication line. The lowpass and highpass filters as well as the low and highpass transformers are optimized for their frequency bands. Further, the edges of the low and high frequency bands are sufficiently separated to reduce interference from the other frequency band. These factors, in part, allow a multiple tone communication device to be capable of operating in multiple modes of operation with multiple DSL varieties.

Abstract: In accordance with the present invention, a loop extender for improving the transmission of digital subscriber line (DSL) signals over a local loop is disclosed. The loop extender includes selectable line termination and equalization (SLTE) DSL amplification circuitry capacitively coupled to the local loop via bypass relay switches, a plain old telephone service (POTS) loading coil adapted to be coupled to the local loop for improving transmission of POTS band signals over the local loop, and a diagnostic/control unit (DCU) coupled to the local loop for receiving and processing control signals from a central office, coupled to the bypass relay switches via a bypass relay for controlling the bypass relay switches, and coupled to the SLTE DSL amplification circuitry via a plurality of switch control lines for controlling the SLTE DSL amplification circuitry.

Abstract: A method, apparatus, and system in which one embodiment includes a network interface device (NID) located outside a building and a power supply unit located inside the building. The power supply unit has an electrical isolation component and one or more ports that couple via a first phone line and a second phone line to the NID to provide isolated DC power to the NID.