Abstract: A signal processor includes an adaptive filter that generates an output signal as a function of an input signal and of weighting coefficients stored in a memory. An error detector generates an error signal as a function of the output signal. The error signal is used in adjusting the weighting coefficients. A data processor adjusts the number of weighting coefficients of the adaptive filter and system resources used for storing the weighting coefficients as a function of a characteristic of the weighting coefficients.

Abstract: A method and apparatus are provided, where the method includes defining a first portion of a memory for receiving data, providing a memory request to transfer data from a source to the first portion of the memory defined to receive the data, and transferring a portion of data from the source to the first portion of the memory according to a priority scheme that determines the sequence of the data transfer, wherein the size of the portion of the data substantially corresponds to the size of the first portion of the memory. The method also includes associating a frame with at least one corresponding memory location containing data in the first portion of the memory, transmitting at least a portion of data from the first portion of the memory within the frame, and receiving an acknowledgement in response to transmitting the data within the frame.

Abstract: A method and apparatus are provided. The method includes providing an enable signal to a configuration device for generating a preselected signal, providing the preselected signal to a peer station over a subscriber line, and adjusting a transmission path of a signal to the peer station through the subscriber line in response to the preselected signal.

Abstract: A communications system includes first and second subscriber lines, a first device, and a second device. The first device has a first negotiation unit coupled to the first subscriber line. The second device has a second negotiation unit coupled to the second subscriber line. The first negotiation unit is adapted to send a first negotiation signal on the first subscriber line. The first negotiation signal induces through cross-talk a second negotiation signal on the second subscriber line. The second negotiation unit is adapted to modify an operating parameter of the second device based on the second negotiation signal. A method for negotiating operating parameters in a communications system is provided. A first negotiation signal is transmitted from a first device coupled to a first subscriber line. The first negotiation signal is received in a second device coupled to a second subscriber line independent of the first subscriber line.

Abstract: A method and apparatus are provided for delivering data within a frame to a peer station, the frame having at least a first and a second symbol. The method comprises determining whether the data in the first symbol is greater than or equal to a coding-gain threshold, loading at least a portion of the data within at least the second symbol in response to determining the data in the first symbol is greater than or equal to the coding-gain threshold to provide a new frame, and transmitting the new frame.

Abstract: A network node configured for transmitting and receiving data to and from other network nodes is able to adapt the transmission rate based on the network conditions. The node initially transmits the data to a receiving node at a first rate. If the data is not received error-free, the node is able to reduce the number of data bits of the current packet that are being transmitted and to increase the amount of redundant data. The node repeats the process until error-free transmission is obtained.

Abstract: A signal detector includes a transform unit and a cross-frame energy level unit. The transform unit is adapted to receive at least a first and a second frame of time domain input samples. The transform unit generates at least a first frequency energy value for the first frame and a second frequency energy value for the second frame based on the time domain input samples. The cross-frame energy level unit is adapted to compare the first frequency energy value to the second frequency energy value to determine the presence of a first tone in the time domain input samples. A method for detecting a signal includes receiving at least a first and a second frame of time domain input samples. At least a first frequency energy value for the first frame and a second frequency energy value for the second frame are generated based on the time domain input samples. The first frequency energy value is compared to the second frequency energy value to determine the presence of a first tone in the time domain input samples.

Abstract: A signal detector includes a transform unit, a gain control unit, and an energy level threshold unit. The transform unit is adapted to receive a plurality of input samples and calculate a first plurality of delay values based on the input samples. Each delay value is based on at least one previous delay value and a current input sample. The transform unit is adapted to calculate a first energy value based on at least a subset of the first plurality of delay values. The gain control unit is adapted to determine if a selected delay value of the first plurality of delay values exceeds a predetermined threshold and scale the selected delay value, the at least one previous delay value used to calculate the selected delay value, and subsequent input samples received after the current input sample by a first amount in response to the selected delay value exceeding the predetermined threshold.

Abstract: A random-access local network having multiple nodes provides data communication across residential wiring such as telephone line as a network medium, where each node accesses the network medium using discrete multi-tone (DMT) modulated symbols. The effects of amplitude and phase distortion of transmitted DMT symbols are overcome, without the necessity of complex equalizers, by differentially encoding data prior to transmission, and recovering the transmitted data by comparing phase differentials between consecutive symbol tones. Each transmitted symbol is composed of a plurality of tone signals, each tone signal modulated according to a constellation point in a complex domain. A transmitter in a first node transmits a training symbol onto a network medium, where the DMT tones of the training symbol have an equal predetermined amount of energy.

Abstract: An apparatus for determining energy threshold detection values for detecting at least one tone having a known frequency and duration in an input signal. The input signal is input over a period of time that is divided into frame portions including at least an initial frame portion and a last frame portion. An energy value is determined for the at least one tone during each frame portion. A set of control flag signals are set for the at least two frame portions based on the energy values being below a threshold value in previous frame portions and the presence of noise in previous frame portions. An offset into a data table is determined based on the control word, the offset being used to retrieve a scaling coefficient and an address of an energy value for the at least two frame portions from the data table.

Abstract: A method and apparatus are provided for accessing data. The method includes defining a first portion of a memory for receiving data and providing a memory request to transfer data from a source to the first portion of the memory defined to receive the data. The method further includes transferring a portion of data from the source to the first portion of the memory, wherein the size of the portion of the data substantially corresponds to the size of the first portion of the memory.

Abstract: A signal detector for detecting at least a first signal having a first frequency includes a matched transform unit and an energy level threshold unit. The matched transform unit is adapted to receive at least a first frame of time domain input samples at a sampling frequency and generate at least a first frequency energy value for the first frame based on at least a first subset of the time domain input samples and a first matched filter coefficient. The sampling frequency is a non-integral multiple of the first frequency, and the first matched filter coefficient depends on the first frequency. The energy level threshold unit is adapted to compare the first frequency energy value to a threshold energy value to determine the presence of the first signal. A method for detecting at least a first signal having a first frequency is provided. The method includes receiving at least a first frame of time domain input samples at a sampling frequency.

Abstract: A telephone that communicates high-quality audio signals and a method for communicating an audio signal with an extended frequency range over a telephone network. The cordless telephone has a handset unit with a sampler circuit, a compression circuit, decompression circuit, as well as analog-to-digital (A/D) and digital-to-analog (D/A) converters, which handset is coupled by an infrared (IR) wireless link to a base unit connected to the Public Switched Telephone Network (PSTN). In one embodiment, the telephone includes a sampler, a compression block, a telephone port, a decompression block, and a digital-to-analog (D/A) converter. The sampler receives a analog audio signal and digitizes the signal into a high-quality (705.6 kbps) digital audio signal. The compression block then encodes the digital audio signal into a compressed digital signal at a lower bit rate (such as 150 kbps or 56 kbps) with a compression algorithm such as MP3.

Abstract: A communications system includes a communications channel, a first processing unit; and interface unit, and an interrupt controller. The first processing unit is adapted to monitor the communications channel and provide a plurality of status bits. The interface unit includes an interrupt register. The interrupt controller is adapted to identify a plurality of interrupts in response to changes in the status bits. Each interrupt has a priority, and the interrupt controller is adapted to store selected interrupts in the interrupt register in an order determined by the priority of the interrupts. A method includes monitoring a communications channel. A plurality of status bits associated with the monitoring are provided. A plurality of interrupts are identified based on changes in the status bits, each interrupt having a priority. Selected interrupts are stored in an interrupt queue in an order determined by the priority of the interrupts.

Abstract: A method and apparatus are provided, where the method and apparatus include associating a frame with at least one corresponding memory location that contains data, transmitting the data within the frame to a peer station, receiving an acknowledgement in response to transmitting the data within the frame from the peer station, analyzing the acknowledgement to determine if the data within the frame transmits successfully, and updating the corresponding memory location with new data in response to determining if the data transmits successfully.

Abstract: A method and apparatus are provided for accessing data. The method includes defining a first portion of a memory for receiving data and providing a memory request to transfer data from a source to the first portion of the memory defined to receive the data. The method further includes transferring a portion of data from the source to the first portion of the memory, wherein the size of the portion of the data substantially corresponds to the size of the first portion of the memory.

Abstract: A transceiver includes a receive unit and a transmit unit. The receive unit is adapted to receive a prefix width parameter. The transmit unit includes a modulator and a cyclic prefix unit. The modulator is adapted to receive digital data and generate an output symbol based on the digital data. The output symbol includes a plurality of waveform samples. The cyclic prefix unit is adapted to receive the output symbol and the prefix width parameter. The cyclic prefix unit generate a cyclic prefix based on a subset of the plurality of waveform samples and prepends the cyclic prefix to the output symbol to generate a transmit symbol. The size of the subset is based on the prefix width parameter. A method for adjusting the symbol rate of a transceiver includes receiving a prefix width parameter and receiving digital data. An output symbol is generated based on the digital data. The output symbol includes a plurality of waveform samples.

Abstract: In the broadcast band having a plurality of channels allocated therein, by using high-side injection and low-side injection as described herein, the noise introduced into the channel by the local oscillator signal can be minimized. The local oscillator signal in combination with the intermediate frequency determines the frequency of the channel signal being produced by the transmitter. The selected high-or low-side injection determines whether the bulk of the power is introduced into the combination frequency signal (i.e., the channel) above or below the local oscillator frequency, thereby moving the local oscillator frequency outside the broadcast band. The non-selected sideband is even further outside broadcast band.

Abstract: A communication device includes a transmitter and a first idle detector. The transmitter is adapted to transmit digital data. The digital data includes user data. The transmitter includes a first idle symbol buffer for storing a first idle symbol. The first idle detector is adapted to detect an absence of user data. The transmitter is adapted to transmit the first idle symbol in response to detecting the absence of user data. A method for transmitting data includes defining a first idle symbol. The user data is stored in a buffer. The user data is modulated to generate a user symbol. An absence of user data in the buffer is detected, and the first idle symbol is transmitted in response to detecting the absence of user data.

Abstract: A communications system includes a first and second modem coupled together via a communications link. The first modem has at least two user devices coupled thereto, and modulates data generated by the user devices on a plurality of tone carriers for transmission to the second modem. The first modem determines the number of user devices coupled to it. Based upon the number of user devices determined, the first modem divides the plurality of tone carriers into a number of subsets corresponding to the number of user devices based upon a predetermined criterion. The first modem then allocates a subset of tone carriers to a respective user device. In one embodiment, the usage rate of each user device is determined, and the tone carriers are reallocated to different subsets as a function of the usage rate of each respective user device.