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: 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 work over loaded subscriber loops that also support a native POTS interface as well as over loaded subscriber loops that are not providing a native POTS interface. Furthermore, although the preferred embodiments of the present invention are intended to address the technical and business problems of service providers delivering digital subscriber line service over loaded loops, the preferred embodiments will also work over unloaded loops.

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: 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 work over loaded subscriber loops that also support a native POTS interface as well as over loaded subscriber loops that are not providing a native POTS interface. Furthermore, although the preferred embodiments of the present invention are intended to address the technical and business problems of service providers delivering digital subscriber line service over loaded loops, the preferred embodiments will also work over unloaded loops.

Abstract: A communication device transmits very low frequency signals in order to help diagnose the cause of a communication problem in a DS L 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 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: Embodiments of the present invention provide communication of Asynchronous Transfer Mode (ATM) data using variable duration ATM frames between a data terminal unit (DTU) at a central office and a remote DTU at a user premises. One embodiment of the present invention can be viewed as a communication device which communicates data in an asynchronous transfer mode (ATM) format, the device comprising at least one buffer configured to receive data from a sending device, and a modulation unit coupled to the buffer and configured to encapsulate a plurality of ATM cells into an ATM frame, the plurality of ATM cells having the received data, so that the ATM frame is communicated onto a subscriber line, such that the communicated ATM frame has a variable transmission duration, the variable transmission duration corresponding to a number of the plurality of ATM cells encapsulated into the ATM frame.

Abstract: An improvement to a half duplex multipoint communication environment wherein a pilot tone enables a control modem to maintain synchronization with a plurality of remote modems. By employing a VCXO in a remote modem, a low jitter timing pulse is generated thus allowing a control modem to maintain synchronization with a plurality of remote modems.

Abstract: The present invention provides a method and apparatus for multi-protocol, point-to-point communications which allocates processing tasks between a processor of an end point device and a processor of a communication device. The processor of the end point device performs all higher level protocol processing and the processor of the communication device performs lower level protocol processing. Internet service providers usually have several modems connected to each host computer for providing simultaneous point-to-point communication with a plurality of end users. The modems normally are located on cards which reside inside of the host computer, which may be a personal computer. To prevent the host processor from having to perform all of the protocol processing tasks for each session, the present invention provides for off-loading at least a portion of the Point-to-Point Protocol processing onto the modem processors. The host and the communication device or devices are interfaced via a shared memory device.

Abstract: A number of arrangements and methods that achieve concurrent communication of analog information and digital information. In general terms, when the communication channel is viewed as a multi-dimensional space, the digital information signal is divided into symbols, and the symbols are mapped onto the signal space with a preset distance between them. The analog signal, generally limited in magnitude to less than half the distance separating the symbols, is converted to component signals and added (i.e., vector addition) to the symbols. The sum signal is then transmitted to the receiver where the symbols are detected and subtracted from the received signal to yield the analog signal components. The transmitted analog signal is recreated from those components.

Abstract: A method and apparatus for control of concurrent communication of analog information and digital information. In general terms, when the communication channel is viewed as a multi-dimensional space, the digital information signal is divided into symbols, and the symbols are mapped onto the signal space with a preset distance between them. The analog signal, generally limited in magnitude to less than half the distance separating the symbols, is converted to component signals and added (i.e., vector addition) to the symbols. The sum signal is then transmitted to the receiver where the symbols are detected and subtracted from the received signal to yield the analog signal components. The transmitted analog signal is recreated from those components. Both half-duplex and full-duplex operation is available in accordance with this invention. The illustrative embodiment includes a controller that is sensitive to input signals applied to the modem disclosed herein.

Abstract: A simultaneous voice and data modem performs "voice-activated" data rate changes to improve the transmission quality of the voice signal. In particular, when the simultaneous voice and data modem detects that a local telephone set has gone "off-hook," the simultaneous voice and data modem selects a signal space with a lower symbol density, which, although resulting in fewer bits per symbol, provides for a higher quality voice transmission.

Abstract: A modem, capable of simultaneously coupling voice and data signals, connects local digital terminal equipment (DTE) and a local telephone to a communications link. To prevent the local DTE from responding to a communications containing only voice signals, the local DTE is notified of an incoming communication only after detection of calling tone signals on the communications link. Such signals indicate a remote DTE desires to establish a data communications path with the local DTE. This operation advantageously prevents the modem from transmitting an annoying answer tone to a calling party.