Abstract: A troubleshooting portal method for providing connectivity between a first communication device and a second communication device. The second communication device resides in an access provider communication system. One embodiment comprises receiving a specification from a user by the first communication device, the specification comprising at least one predefined identifier that identifies the second communication device, and receiving a request to establish connectivity between the user and the second communication device; associating the predefined identifier with said second communication device; establishing connectivity between the first communication device and the second communication device based upon the specified predefined identifier; receiving at least troubleshooting data and a test from the user; and communicating the received troubleshooting data and the test to the second device.

Abstract: Systems and methods for automatically discovering the configuration of network and/or communication facilities are provided. The determination generally involves receiving and/or sending at least one test message or packet with special characteristics that normally would be filtered by filtering/forwarding entities in connectionless routed cores, but normally would be forwarded by connectionless communication facilities. If the communication facilities do not contain the filtering/forwarding entity, the at least one test packet will be forwarded or passed through the communication facilities. If the at least one test packet is filtered or not passed, then at least two scenarios are possible. First, the at least one test packet may be filtered and may be silently discarded in which case a determination that the network did not pass the at least one test packet may be made based upon a timeout of a counter.

Abstract: A method for testing subscriber loop conditions includes receiving test signal data from a test signal provider, receiving a request for transmitting a test signal described by the test signal data, and transmitting the test signal over a communication channel. The test signal may correspond to a pre-qualification test signal, a qualification test signal, or an in-service test signal. Test results may be transmitted to the test signal provider or to some other designated recipient.

Abstract: The preferred embodiments of the present invention generally provide improved communications over a subscriber loop that is loaded with at least one and potentially a plurality of load coils. The preferred embodiments of the present invention will support digital subscriber line service over loaded subscriber loops that also support a native POTS interface and offer various techniques for advantageously arbitrating use of the 0-4 KHz baseband between POTS and DSL. Furthermore, the rapid start and stop DSL modulation techniques as well as various mechanisms such as protocol spoofing allow DSL service to appear to be always-on for many end user applications even though DSL communication may cease for POTS signaling messages and completed POTS telephone calls.

Abstract: Systems and methods for encoding fractional bit rates in a communication system, such as a pulse amplitude modulation (PAM) communication system, are provided. The systems and methods enable a first transceiver to specify to a second transceiver a desired fractional bit rate for transmitting data to the first transceiver. In this manner, the systems and methods of the present invention for the first time enable a single standardized specification of a generalized transmitter that may be used to implement any type of fractional encoding or mapping.

Abstract: A symbol timing derivation system derives receiver timing from received symbols which avoids the need for a pilot tone, thereby reducing power consumption and expanding usable bandwidth. The system is implemented by using a calculation that finds the timing phase error. The timing phase error is then averaged and controls a phase locked loop (PLL). This PLL in turn controls a voltage-controlled oscillator, which handles the modem receiver timing. A centroid calculation can be included to bias the voltage-controlled oscillator to push the equalizer coefficients back to the ideal position. The system can be implemented in either a point-to-point modem environment or a multi-point environment, for example, but not limited to, MVL or DMT. The voltage-controlled oscillator may also be implemented to control transmitter timing, so that the central office modem and the remote modem will operate more-or-less synchronously, reducing the need for large equalizer corrections at either end.

Abstract: A single subscriber line multi-point communication system is disclosed. In general, the multi-point communication system can include a first transceiver coupled to a subscriber line capable of transmitting and receiving at least two modulation methods, either of said modulation methods being operable to transmit a test signal, and a second transceiver coupled to said subscriber line capable of transmitting and receiving said at least two modulation methods, the second transceiver being operable to receive the test signal and determine at least one channel parameter from the test signal. A master transceiver that can be used in various embodiments of a single subscriber line multi-point communication system, and a tributary transceiver are further disclosed.

Abstract: A communication device transmits very low frequency signals in order to help diagnose the cause of a communication problem in a DSL communication system. The communication problem may be, for example, the inability of a remote data transceiver unit (DTU-R) to successfully train-up with a central data transceiver unit (DTU-C). The very low frequency signals may be used to communicate the status or settings of the remote transceiver unit to the DTU-C, to download settings parameters or executable code to the DTU-R, or to coordinate the transmission of testing signals.

Abstract: Several embodiments of a space diversity trellis interleaver system are provided for communicating data over a plurality of separate communication paths in order to inhibit distortion caused by impulse noise or other correlated noise and enhance the data transmission rate of data communications. The transmitter is designed to receive a plurality of data streams from data terminal equipment (DTE), which can be one or more devices. One or more convolutional encoders, preferably trellis encoders, encode each of the data streams. In an alternative embodiment, more than one trellis encoder is used to trellis encode each data stream. Data segments from the convolutionally encoded data streams are interleaved with a switch. The plurality of interleaved convolutionally-encoded data streams are modulated and transmitted onto a respective plurality of separate communication paths. At the receiver, the plurality of data streams is received from the separate communication paths and demodulated.

Abstract: A DSL device performs a frame check sequence operation in a digital signal processor (DSP), i.e., layer one of the OSI seven layer model, heretofore performed only in layer two of the OSI seven layer model. Performing the layer two framing and calculating the frame check sequence in the DSP allows the DSP to use the layer two error detection results, and optionally, the mean squared error vector, to more accurately determine whether to update adaptive receiver parameters.

Abstract: A communication device for use in a non-self synchronizing scrambling (NS3) communication system and a method for using NS3 in a communication system are disclosed. A digital data stream is scrambled by modifying the digital data stream based on a pseudo-noise sequence (PNS) to produce a scrambled digital data stream. The PNS has a timing reference that is distinct from the digital data stream. The scrambled digital data stream is capable of being descrambled by performing an inverse modification, based on the same PNS and the same timing reference. The scrambled digital data stream may be transmitted over a communication medium and descrambled at the opposing end of the communication medium. Synchronization between the scrambler and the descrambler is maintained by providing a common timing reference to the scrambler and the descrambler. The common timing reference is distinct from the data stream.

Abstract: A digital subscriber line (DSL) driver allows a transmitter to monitor its own transmit spectrum at the subscriber loop and adjust the transmit spectrum based on detected line conditions, affected by the presence of bridged taps or any other impedance variations. The transmit spectrum is preferably equalized so that all carriers, or tones, transmit using the same power and exhibit the same margin. The invention is applicable to DMT and single carrier modulation formats.

Abstract: Systems and methods are provided for communicating data over a subscriber loop using a modem. One such method includes: transmitting data on the loop in a first frequency band; sensing an indication that simultaneous transmission on the loop in a POTS frequency band is imminent; and adjusting transmit power in the first band, in response to the sensing step. One such system includes an input/output connection in communication with the loop, a processor operable in at least two states, a means for sensing demand for simultaneous usage of the loop, and a means for controlling the state. The first state is characterized by a first transmit power spectrum in the first band. The second state is characterized by a second transmit power spectrum in the first band, reduced relative to the first spectrum. Upon sensing demand, the control means causes the processor to operate in the second state.

Abstract: Systems and methods for integrating analog voice service and derived POTS voice service in a DSL environment are provided. One embodiment is a system comprising: a first communication path for carrying plain old telephone service (POTS) voice signals between a telephone-type device and a subscriber line of a telephone network; a second communication path for carrying derived POTS voice signals between the telephone-type device and the subscriber line; and a switching mechanism configured to switch the telephone-type device between the first communication path and the second communication path.

Abstract: A communication device transmits very low frequency signals in order to help diagnose the cause of a communication problem in a DSL communication system. The communication problem may be, for example, the inability of a remote data transceiver unit (DTU-R) to successfully train-up with a central data transceiver unit (DTU-C). The very low frequency signals may be used to communicate the status or settings of the remote transceiver unit to the DTU-C, to download settings parameters or executable code to the DTU-R, or to coordinate the transmission of testing signals.

Abstract: A discrete multitone interleaver system, including an interleaver and deinterleaver, are provided for efficiently communicating data despite noise affecting a Discrete Multitone modulation (DMT) system. The discrete multitone interleaver includes a convolutional encoder capable of receiving a plurality of bits on tones and capable of outputting a convolutionally encoded plurality of bits and a synchronized dual skipping switch capable of passing the plurality of bits on tones to the convolutional encoder in a non-sequential order and capable of outputting the convolutionally encoded plurality of bits in the same non-sequential order.

Abstract: A tone ordered discrete multitone interleaver system and method, including a tone ordered interleaver and deinterleaver, are provided for efficiently communicating data despite noise affecting a Discrete Multitone modulation (DMT) system. The tone ordered discrete multitone interleaver forces interleaving of trellis encoded information by assigning a different number of bits to adjacent tones or adjacent tone pairs.

Abstract: The present invention injects and/or removes voice data into and/or out-of an Ethernet stream in a dynamic, Time Division Multiplexer-like manner, thus providing optimum quality Voice with minimal impact on data bandwidth.

Abstract: Fractional bit rate encoding in a discrete multi-tone (DMT) communication environment allows the transmission of fractional bit rates, thus maximizing the use of signal-to-noise ratio (SNR) available on each of the DMT carriers, or tones, while maintaining a constant power density over the entire frequency spectrum.

Abstract: The eavesdropping prevention system and method of the present invention provides for shunting leakage signals in a communication system. The amplifier-based coupler is constructed with amplifiers configured with a nearly-zero impedance path which effectively prevents the propagation of a leakage signal onto other communication connections which are coupled to the same communication device. Leakage signals are attenuated due to the nearly-zero impedance path, rather than propagating through the higher impedance communication connections.