Abstract: A multi-channel DSL communication link in accordance with the present invention may comprise a plurality of N DSL transceivers each configured with at least two bi-directional serial data interfaces with the first interface of a first transceiver coupled to a communication interface and the second interface of the first transceiver coupled to a first bi-directional serial data port of a second transceiver. Subsequent transceivers may be coupled in this manner with its Nth?1 and Nth+1 nearest transceivers. A method for transferring data between multiple transceivers is also disclosed, which can be described as follows: recovering a mapped portion of a downstream data stream at each of N DSL transceivers; communicating the portion to the next closest transceiver to a communication interface; and mapping an upstream data stream for transmission via the N transceivers; using each respective transceiver's second data interface to communicate a mapped portion to the next furthest transceiver.

Abstract: The present invention is directed to a signal processing and amplifying system that uses advance knowledge of a digital signal, before it is converted to analog form and applied to the input stage of the amplifier stage, to “intelligently” amplify the signal with the maximum power efficiency and minimal distortion. This advance knowledge of the digital signal allows a switch control logic (SCL) unit to open and close solid state switches and seamlessly turn off and on the low and high power stages correctly to minimize the amplifier distortion while conserving power. In one embodiment, the system comprises a shift register, which receives the supplied digital signal to be amplified and delays the digital signal by a known amount, a digital to analog converter, an amplifying circuit, which is made up of at least two amplifiers, and an SCL unit. The SCL unit comprises control logic, and multiple solid state switches.

Abstract: A sketching system sketches first notes to be transmitted over a telephone line receives second notes from another sketching system. The sketching system includes a signal de-combiner device, receiving the second notes from the another sketching system and voice data as a combined signal via the telephone line and de-combining the combined signal into the second notes and the voice data. In addition, the sketching system includes a sketching unit connected to the signal de-combiner. The sketching unit includes a note displaying device displaying the first and second notes, a note generating device generating the first notes, and a processor connected to the note displaying and generating devices and to the signal de-combiner, receiving the first notes from the note generating device, receiving the second notes to the note displaying device.

Abstract: A first phase change is introduced to an analog signal based on a symbol specified by a data signal, where the symbol is one of a plurality of symbols in a symbol constellation. The analog signal is added to the data signal to form a combined signal which is transmitted over a communication channel that introduces a channel phase change to the analog and data signals. After transmission through the communication channel, the combined signal comprises a phase changed analog signal and a phase changed data signal. A received symbol is specified by the phase changed data signal, and a phase shift is introduced to the phase changed analog signal based on the identity of the received symbol.

Abstract: A sketching system sketches first notes to be transmitted over a telephone line and receives second notes from another sketching system. The sketching system includes a signal de-combiner device, receiving the second notes from the another sketching system and voice data as a combined signal via the telephone line and de-combining the combined signal into the second notes and the voice data. In addition, the sketching system includes a sketching unit connected to the signal de-combiner. The sketching unit includes a note displaying device displaying the first and second notes, a note generating device generating the first notes, and a processor connected to the note displaying and generating devices and to the signal de-combiner, receiving the first notes from the note generating device, receiving the second notes from the de-combiner, and transmitting the first and second notes to the note displaying device.

Abstract: In a simultaneous voice and data communications system comprising two modems, an autorate feature is implemented in one illustrative method by adding a silence detector to the receiver circuitry of at least one of the modems in such a way that noise statistics for the communications channel are only accumulated during intervals of silence. If the resulting noise statistics exceed a predetermined threshold, i.e., the communications channel is too noisy, the receiving modem negotiates a lower data rate with the transmitting modem. In another illustrative method, the transmitting modem provides a signal, which represents an interval of silence, to the receiving modem. Upon receipt of the signal, the receiving modem accumulates error statistics in order to determine if the communications channel is too noisy.

Abstract: A method and apparatus for 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 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 the disclosure.

Abstract: In a simultaneous voice and data communications system, a voice signal is added to a data signal before transmission over the public switched telephone network (PSTN). In particular, in every signaling interval, a signal point is selected for transmission as a function of both the voice signal and the data signal. Since the voice signal is effectively offset by the data signal, compandors normally found in the PSTN are not effective in improving the signal to noise ratio of the transmitted voice and data signal. Therefore, the voice signal is additionally companded in the transmitter before transmission over the PSTN. This additional companding by the transmitter improves the signal to noise ratio of the combined voice and data signal.

Abstract: A simultaneous voice and data (SVD) communications system includes an SVD modem at either endpoint of the system. Each SVD modem provides an SVD signal to the opposite endpoint, where this SVD signal includes both a voice channel and a data channel. One, or both, of these SVD modems allows the respective user to alter either the voice signal that is provided to that user, or the voice signal that is transmitted from that user, via the voice channel of the SVD signal, to the opposite SVD endpoint.

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 communications system simultaneously transmits both a primary data signal and a secondary voice signal in such a way that the dynamic range of the secondary voice signal is increased even though deliberate errors are introduced into the transmitted data portion of the signal. In particular, the communications system includes an error correcting technique like channel encoding and the constellation signal space is divided into a number of regions, where at least one of the regions overlaps with another region. The primary signal is channel encoded to select a particular one of the number of regions, the region being represented by a reference signal point value. The voice signal is encoded to provide a signal point vector, which is added to the reference signal point in such a way that the resultant signal point is located in the overlapping region thereby deliberately introducing an error into the resulting transmitted signal point stream.

Abstract: In a simultaneous voice and data communications system, a voice signal is mapped into an N-dimensional signal space constellation as a vector, and added to a reference signal point, i.e., a data symbol, where the data symbol is selected from a constellation of data symbols every signaling interval as a function of a data signal. The constellation signal space is further divided into a number of shaped regions, where each region is associated with a different one of the data symbols. The shape of each region is selected as a function of the characteristics of the voice, or audio, signal. In particular, each region illustratively has a rectangular shape.

Abstract: A method and apparatus for 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 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 the disclosure.

Abstract: An analog signal is added to a data signal that specifies a symbol in a symbol constellation to produce a combined signal that is transmitted to a receiver. The symbol constellation is picked from a plurality of symbol constellations having differing symbol densities based on the amplitude of the analog signal.