Abstract: A system and method for transmitting data between a first and second ADSL DMT modem. The system includes a plurality of user devices coupled to the first modem for generating user data. A buffer, coupled between the user devices and the first modem, accumulates a predetermined amount of user data. When the predetermined amount of user data is accumulated in the buffer, the first modem modulates the predetermined amount of accumulated data to generate a DMT symbol, and transmits the symbol to the second modem. The second modem, upon receiving the symbol, demodulates the symbol and recovers the user data respectively corresponding to each of the user devices.

Abstract: A passive echo cancellation circuit for reducing echoes on a subscriber line includes an output driver adapted to drive a downstream signal on the subscriber line. First sensing circuitry is coupled to the output driver and adapted to sense a current on the subscriber line to generate a first voltage. A balancing network is adapted to receive at least a portion of the downstream signal. Second sensing circuitry is adapted to sense a current in the portion of the downstream signal passing through the balancing network to generate a second voltage. An upstream driver is adapted to subtract the second voltage from the first voltage to generate an upstream signal.

Abstract: A free channel selector for selecting from a plurality of channels an optimal channel for establishing radio communication. The channels may be selected by a radio frequency (RF) module for outputting sampled signals carried on that channel. The selected signals are digitized and provided to a peak detector. The peak detector compares the strength of the signals from the various channels. A memory device, having an array of cells, is provided for storing values representative of the sampled signals of each of the plurality of channels, each of the stored values being stored in a cell having an address indicative of the channel on which the signal represented by the stored value is carried. A stored value corresponding to the lowest signal strength is selected as being the free channel. Communication will then occur over that channel.

Abstract: A bicycle wheel rim can be worn down by rim brakes, leading to serious accidents. The present invention relates to a novel bicycle rim that provides direct and clear indication to a rider when a braking surface on the rim has been worn off. The novel bicycle rim comprises a base portion, two lateral flanks forming an outer braking surface, and a longitudinal hole. The braking surface has a first portion and a second portion. The first portion of the braking surface has a thickness that is designed to be worn off down to the longitudinal hole so as to form a visible slit, while the second portion, situated radially outwards with respect to the first portion, has a thickness such as to prevent deformations of the second portion when the first portion is worn off down to the longitudinal hole.

Abstract: A physical layer device (PHY) device in a home LAN employs discrete multitone technology (DMT). The DMT system enables usage of existing residential wiring, which typically is telephone system grade twisted copper pair. The PHY device comprises a spectral image selection circuit to increase frequency diversity by examining all the images captured by a filter and restoring the transmitted signal based upon an image that may not be associated with the carrier frequency but its harmonics. Alternatively, the PHY device adjusts the sampling rate of its digital to analog convertor and accordingly filters to achieve desired grouping of spectral images.

Abstract: A physical layer device (PHY) device in a home LAN employs discrete multitone technology (DMT). The DMT system enables usage of existing residential wiring, which typically is telephone system grade twisted copper pair. The PHY device comprises an analog front end (AFE) circuit that frequency shifts the spectral images by using a clock signal. The multiplication of the clock signal is accomplished using a digital mixer or, in the alternative, an analog switch.

Abstract: A semiconductor process is disclosed which forms a field plate structure that integrally contacts an emitter region of a bipolar junction transistor by construction, without intervening interconnect layers or contacts. In one embodiment, a single-layer polysilicon electrode forms a field plate electrode which integrally interconnects to a traditional diffused emitter region formed before the polysilicon layer is deposited. This allows for deeper emitter regions required by the deep base regions needed for high-voltage bipolar devices. Moreover, the polysilicon layer, including the polysilicon electrode forming the field plate electrode, may be used as a local interconnect layer.

Abstract: A random access data network in accord with the invention will utilize discrete multi-tone (DMT) transmission over a link within a home or other premises, such as over existing in-house telephone wiring. Discrete multi-tone communication in a random access implementation raises a number of timing issues. To address these issues, all packet transmissions through the network will begin with one or more cycles of a defined periodic signal, typically a sinusoid at a specified frequency. All timing of decoding of subsequent signals, such as ID signals and DMT symbols, is based on counting signal sampling intervals following the detected timing mark. The preferred embodiment utilizes differential modulation of the tones within the DMT symbol. Each packet may include a reference symbol to enable demodulation of the first DMT data symbol. Also, the preferred embodiment of the DMT symbol includes a prefix code followed by the actual DMT waveform carrying the modulated information.

Abstract: A semiconductor process is disclosed which forms openings in a dielectric layer through which the base region of both high-voltage and high-gain bipolar transistors are formed. In one embodiment of the invention, the openings for the high-gain transistors are first protected by a photoresist layer that is patterned to expose the openings for the high-voltage transistors. A first base implant is performed through the exposed windows in the dielectric layer and into the exposed substrate or epitaxial layer therebelow, and then diffused to a suitable depth. The patterned photoresist is then removed to additionally expose the openings for the high-gain devices, and a second base implant is performed, this time into both base regions, and then diffused to a suitable depth. Emitter regions are then formed within the base regions of both transistor types by traditional implantation and contact techniques.

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 modulates data, such as a bit-pair, to a new constellation point based on the value of the bit-pair and a prior position of a consecutively-preceding constellation point, such that the data is represented by the difference in positions between the consecutively-preceding constellation point and the new constellation point.

Abstract: An apparatus and a method a method for testing, configuring, and evaluating a transmission line. The method receives a set of command and data signals through an input/output interface and processes the command and data signals from the input/output interface for controlling at least one relay. The method also activates at least one switch for testing and improving a transmission signal line using the relay and testing and emulating the transmission signal line based upon the activated switch. The method also configures the transmission signal line based upon the testing and emulating.

Abstract: A method and apparatus are provided, where 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 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.

Abstract: The present invention addresses signal noise problems associated with telecommunications. In particular, echo cancellation is addressed by the present invention, which employs an inventive adaptive filtration scheme. In one aspect of the invention, a method is provided for controlling an adaptive balance filter. In another aspect of the invention, an apparatus is provided for controlling an adaptive balancing filter, comprising: a transmit path; an adaptive balance control circuit; and a receive path.

Abstract: The invention is, in its various aspects, an apparatus and a method for scanning a keypad or a keyboard. The apparatus comprises a keypad and an integrated circuit. The keypad includes a plurality of chained resistors and a plurality of key switches. Each of the plurality of key switches is tied to a common node at a first terminal thereof and tapping the chained resistors at a second node thereof. Each of the key switches generates a signal indicative of the respective key switch being pressed when the key switch is pressed. The integrated circuit is capable of receiving the generated signal. The integrated circuit furthermore includes an analog to digital converter capable of generating a reference signal and a circuit capable of determining which key switch has been pressed from the magnitude of the generated voltage signal and the reference signal.

Abstract: A method and apparatus are provided for supporting a plurality of user transceivers with a host transceiver. The method includes allocating at least one symbol of a DMT frame to a first user transceiver of the plurality of transceivers, providing a control signal from a second user transceiver of the plurality of transceivers to the host transceiver, allocating at least one symbol of the DMT frame to the second user transceiver in response to the control signal.

Abstract: A speech recognition system utilizes multiple quantizers to process frequency parameters and mean compensated frequency parameters derived from an input signal. The quantizers may be matrix and vector quantizer pairs, and such quantizer pairs may also function as front ends to a second stage speech classifiers such as hidden Markov models (HMMs) and/or utilizes neural network postprocessing to, for example, improve speech recognition performance. Mean compensating the frequency parameters can remove noise frequency components that remain approximately constant during the duration of the input signal. HMM initial state and state transition probabilities derived from common quantizer types and the same input signal may be consolidated to improve recognition system performance and efficiency. Matrix quantization exploits the “evolution” of the speech short-term spectral envelopes as well as frequency domain information, and vector quantization (VQ) primarily operates on frequency domain information.

Abstract: A method and apparatus for allowing developers to develop software for their product. The method includes providing a first mode signal to a processor to operate in a development mode. The method also includes executing instructions stored in a first region of the memory in response to the first mode signal, providing data to the processor, and writing the data into a second region of the memory.

Abstract: In order to reduce the noise components in a multiplexed communication system, noise components generally referred to as splatter that from the rapid transition between the transmitting state and the non-transmitting state, this power transition in the transmitted signal is provided with a ramped envelope. In the preferred embodiment, the ramped power transition is the result of a ramped enabling signal applied to the power amplifier generating the transmitted signal. The use of a ramped power transition reduces the noise introduced as a result of an abrupt power transition. In addition, the transmitted signal is provided with a preamble so that no data is transmitted during the transition period.

Abstract: A system includes a detector, a first and second processor, and a reset circuit. The detector delivers a first signal in response to detecting a preselected condition, such as low battery voltage. The first processor receives the first signal and delivers an acknowledge signal indicating that the first processor will enter a reset mode of operation in response to receiving a reset signal. The second processor enters the reset mode of operation in response to receiving the first signal. The reset circuit delivers a reset signal to the first processor in response to receiving the first signal and the acknowledge signal so that the first processor is reset when it has acknowledged that it is ready to do so.

Abstract: The present invention comprises a telephone system and method that identify and announce the caller and/or the callee of an incoming telephone call. After receiving a telephone call from a caller, the telephone system answers the incoming telephone call. The identity of the caller is then determined. The telephone system prompts the caller to say his/her name. The name is recorded and repeatedly played back through a built-in speaker announcing the name of the caller to the users of the telephone. The telephone system may also ask the caller to say the name of the callee. In that case, the name of the callee is also recorded and repeatedly played back. The name of the caller and the name of the callee are both announced to the users of the telephone.