Abstract: The invention provides a novel method of transmit beamforming, which allows compact analog implementation of complex digital algorithms without compromising their features. It is aimed to support envelope shaping, apodization, and phase rotation per channel and per firing. Each of three embodiments represents a complete transmit channel driven by pulse-width modulated (PWM) waveforms stored in a conventional sequence memory. PWM signals controls the transmit pulse envelope (shape) by changing the duty cycle of the carrier. Beamformation data are loaded prior to a firing via serial interface. Under the direction of a controller, the circuitry allows high precision (beyond sampling rate) phase rotation of the carrier. It also provides transmit apodization (aperture weighting), which maintains an optimal trade-off among low sidelobe level and widening of the mainlobe. Implementing such an IC, the manufacturing cost of a high-end ultrasound system can be reduced.

Abstract: A signal transmitting apparatus includes a sending part and a receiving part. The sending part converts each width of a plurality of digital input signals into a voltage in accordance with a predetermined weight, generates a send signal by adding voltages converted from the plurality of digital input signals, and outputs the send signal. The receiving part receives the send signal from the sending part, compares the send signal with a plurality of predetermined voltages, generates each of the digital input signals, and outputs each of the digital input signals.

Abstract: A method for transmitting signals along an interconnect in a VLSI system comprising receivers is disclosed. The VLSI based systems operate in the high Giga hertz range. The signals are transmitted along the interconnect as a localized wave packet i.e. as a pulse. The interconnect may be either electrically linear or nonlinear in nature.

Abstract: A system samples data of a digital pulse. The system includes a processor, an integrator, and a converter. The processor computes a discrete Fourier transform of frequency data of the digital pulse. The discrete Fourier transform includes a first output. The integrator integrates the first output to produce phase data. The phase data includes a second output. The converter applies an inverse discrete Fourier transform to the second output to produce a continuous signal that may be sampled at a predetermined time instant.

Abstract: A system and method for communication channel and device control via an existing audio channel. A combined communication signal is received from a communication device comprising an audio signal and a modulated carrier signal via an audio channel. The audio signal is separated from the carrier signal. Digital data is extracted from the carrier signal. Device control is performed utilizing the extracted digital data.

Abstract: The invention provides an apparatus and a method for performing a calculation operation with at least one input signal consisting of signal sections, wherein each signal section of said input signal has a constant amplitude. The apparatus comprises a signal transformation unit for transforming at least one input signal into a first intermediary signal having a virtual amplitude with respect to at least one carrier signal. The calculation unit is provided for performing the calculation operation on said first intermediary signal to generate a second intermediary signal. A signal re-transformation unit re-transforms the second intermediary signal into an output signal consisting of signal sections, wherein each signal section of said output signal has a constant amplitude.

Abstract: A method and apparatus for interrupting a transmission of a multicast signal includes a common channel selector (106) coupled to a receiver (102) to receive common channel information (116) therefrom. A repetition value calculator (108) receives measurement occasion information (118) from the common channel selector (106) to calculate a repetition factor (120). A system frame number comparator (110) determines if a channel measurement occasion (128) should be performed based on the repetition factor (120), a common identifier (124) and a largest common channel transmission time interval (122). The method and apparatus further includes a measurement occasion generator (112) coupled to the system frame number comparator (110), wherein if a measurement occasion is to be performed, a measurement occasion command signal (126) is provided to the measurement occasion generator (112) and the measurement occasion generator generates the channel measurement occasion (128).

Abstract: A master device for communicating with a number of slave devices through a communication link having a limited resource. The master device comprises a transceiver adapted for communicating with the slave devices on the communication link and a controller adapted for detecting the number of slave devices. The controller is adapted for determining an individual resource associated with a slave device to be consumed from the communication link, wherein a sum of the individual resources of all slave devices is lower than the limited resource and wherein the transceiver is adapted for assigning the individual resources to the associated slave devices.

Abstract: An ultra-wideband clear channel assessment system uses a double-window energy technique for energy detection, which indicates a clear or busy channel.

Abstract: A time period control unit controls a time length “TU” of each of unit terms “U” in a variable manner. A pulse-width modulating unit is arranged by a holding unit, a counting unit, and a waveform generating unit. The holding unit holds thereinto a plurality of data “XD” every unit term “U”, which are sequentially supplied, as data “XE.” The counting unit changes a count value “X” during each of the unit terms “U.” The waveform generating unit generates such a pulse-width modulating signal “S” that pulses “P” have been arranged every unit term “U”, while time points when a large/small relationship between the count value “C” and a numeral value of the data “XE” held by the holding unit is inverted are defined as edge portions of the pulses.

Abstract: A system for controlling the delay applied to one branch of a pulse width modulation amplifier. The delay typically incorporated whether input signal level is low and diminished when the input signal level increases. The system may be implemented using a switch, a level detector and a timer, which in conjunction determine whether the delay unit is included in the branch or bypassed. The system may also use a programmable delay that can adjust the period of delay applied or be programmed to operate as a pass-through where delay is no longer beneficial for providing high signal quality.

Abstract: A technique of operating a communication device includes identifying a signal null associated with a signal to be transmitted on a first communication channel. A channel gain of the first communication channel is adjusted at a time that substantially coincides with the signal null to reduce transient noise spectrum coupled from the first communication channel to one or more second communication channels.

Abstract: A pulse width modulation (PWM) Regulator System with automatically switching pulse skipping mode (PSM) is disclosed. The PWM regulator system comprises a PWM regulator, a PSM switching module and a pulse generator. The PWM regulator converts the input voltage by PWM. The PSM switching module determines to enter or exit the PSM. The pulse generator adaptively produces pulse signal for the switching regulator to operate in PSM.

Abstract: A pulse width modulation (PWM) Regulator System with automatically switching pulse skipping mode (PSM) is disclosed. The PWM regulator system comprises a PWM regulator, a PSM switching module and a pulse generator. The PWM regulator converts the input voltage by PWM. The PSM switching module determines to enter or exit the PSM. The pulse generator adaptively produces pulse signal for the switching regulator to operate in PSM.

Abstract: A special data including communication wire continuous dominant levels of a number of N more than the transceiving bit number of n of communication wire continuous dominant levels, set in a character as one unit of communication data, can be transceived by a widely-used serial communication interface such that a predetermined transmission rate is changed to n/N times the transmission rate only when the special data is transmitted, whereby the special data can be easily transceived at a low cost.

Abstract: A control signal is wirelessly transmitted from a first radio communication unit of a portable communication device to a second radio communication unit. The portable communication device is provided for radio communication over a first radio frequency band using a first modulation technique. The control signal is transmitted by generating a control signal, switching off the first modulation of a carrier signal, shifting the frequency of the carrier signal from a first radio frequency band to a second radio frequency band for the first radio communication unit, switching on the second modulation of the carrier signal having a frequency within the second radio frequency band, wherein the carrier signal is modulated with the control signal, and transmitting the control signal modulated carrier signal wirelessly over the second radio frequency band to the second radio communication unit.

Abstract: A multiphase encoded protocol has sufficient density of commands to allow a rich language to be realized on a bus. When ten field bits are dedicated to commands, it is possible to have more than six million words to choose from per clock. Architecture to implement the multiphase encoded protocol and synchronize the bus includes an extracted clock, a command element, and a data element. One-bit multipliers are used as correlation elements to provide feedback into slaved delay-locked loop (DLL) devices, which provides precise phase alignment for successful data extraction of several channels.

Abstract: The present invention extends to methods, systems, and computer program products for failed message error recovery using application specific error queues. An application message, a reference to a receive queue that corresponds to a receiving application, and a reference to an application specific error queue specific to a sending application are received from the sending application. The application message is enqueued in a transmission queue. Transfer of the application message to the receive queue is attempted. It is detected that the application message was not delivered to the receiving application due to an error. The application message is moved from the transmission queue to the application specific error queue. The application message and appropriate error information is returned from the application specific error queue to the sending application.

Abstract: A pulse width modulator for use in a digital amplifier, includes a pop noise reducer for reducing pop noise by controlling a width and a phase of a pulse of a PWM signal output from the pulse width modulator, wherein the pop noise reducer contains: a PWM pulse register for storing a width and a phase values of a pulse of the PWM signal; and a pulse generator for outputting the PWM signal according to the values stored in the PWM pulse register. The pulse width modulator reduces pop noise generated when power supply to a digital amplifier is started and interrupted.

Abstract: An apparatus with ultra wide band (UWB) applications such as radar, position tracking and communications, for example Ground Penetrating Radar (GPR) and Wireless Personal Area Networking (WPANs). An apparatus synchronises a receiver to a received UWB signal having a known hopping code. The apparatus determines a parameter of the signal in a number of time slots; adds the parameter associated with each time slot to a number of corresponding of time and code offset accumulators; and determines the code and time offset accumulator having an accumulated value according to a predetermined accumulator metric as the code and time offset required to synchronise the receiver.

Abstract: The present invention provides a parallel pulse code modulation system enabling the independent control of a plurality of groups of one or more electronic devices. A memory unit receives control data from an external source, and a multiplexer connected to the memory unit receives control data therefrom and organizes it into a serial data stream. A shift register connected to the multiplexer receives the serial data stream and translates groups of data into parallel data stream output, representing control parameters for a particular group of one or more electronic devices. A latch connected to the shift register and to the groups of electronic devices receives each parallel data stream output and sends a particular parallel data stream output to a corresponding group electronic devices. A logic sequencer provides sequencing and timing signals to the memory unit, the multiplexer, the shift register and the latch.

Abstract: In a method for transmitting data between a master control unit and a slave control unit, the master control unit (4) outputs a pulse width-modulated signal (7) at an output terminal (HI_LO_BUS) in order to transmit the same to the slave control unit (5) via a bus (6). The method includes the steps: —the slave control unit (5) generates an acknowledgement signal at periodic acknowledgement intervals (TQuitt); —the slave control unit (5) influences the pulse width-modulated signal (7) transmitted on the bus (6) during the acknowledgement interval (TQuitt); —the master control unit (4) detects the influenced pulse width-modulated signal (7), the pulse width-modulated signal (7) output at the output signal terminal (HI_LO_BUS) being read back at an input signal terminal (Read_Back_Bus) of the master control unit (4).

Abstract: Various embodiments are described for adaptive puncturing techniques involving an adaptive bit loading block to select a modulation scheme and a puncturing pattern for each of a plurality of subcarriers or subcarrier bands based on subcarrier channel state information.

Abstract: A communication system performs bidirectional communication through a same communication path every communication cycle period between a master station and a slave station. From the start of the communication cycle period until an interval period shorter than the communication cycle period elapses, the master station transmits master data represented at a first ratio of first pulse width to the communication cycle period to the slave station. In a remaining period after the interval period in the communication cycle period, the slave station transmits slave data represented at a second ratio of second pulse width to the interval period to the master station.

Abstract: This permits the transmission of signals over the electricity network in such a way that the spectral density of power is adjusted to the regulations in the current rules by means of the possibility of introducing notches in transmission in an efficient manner. It is characterised by the adjustment of the power in one or more carriers of an OFDM signal for generating these notches, through the use of IDFTs of at least 1024 points (if the IDFT is complex) or at least 2048 points (if the IDFT is real) and through the use of a window to multiply the symbols to be transmitted in time.

Abstract: There is provided a digital communication device for performing data communication by selecting an appropriate modulation encoding method. Quality measurement means measures the line quality of data communication from a reception signal. Adaptive modulation control means compares the line quality measured by the quality measurement means to a threshold value obtained from the interrelationship between the line quality in a plurality of modulation encoding methods and the through-put characteristic, thereby selecting one of the modulation encoding methods. Here, the adaptive modulation control means uses as the threshold value a value of the line quality at the intersection of two curves indicating the aforementioned characteristic under a condition having no disturbance among the plurality of modulation encoding methods.

Abstract: A method for dual-tone multi-frequency (DTMF) signaling is implemented in a communication device and comprises the following steps. Transmission of a DTMF event of a digit is triggered if a button-down event occurs. A packet carrying the DTMF event with assigned non-zero event duration is generated regardless of the currently-detected duration of the button-down event. The packet is transmitted over a communication channel.

Abstract: A semiconductor integrated circuit which transmits voice data as ancillary data while maintaining transmission quality without increasing the number of transmission cables in a system for carrying out serial transmission of image data as main data. The semiconductor integrated circuit includes a main data transmitting circuit for converting main data into serial data and transmitting the serial data via at least one transmission path in synchronization with a clock signal, and an ancillary data transmitting circuit for pulse-width-modulating the clock signal by using ancillary data to generate a modulated clock signal having at least three kinds of pulse widths in a predetermined order and transmitting the modulated clock signal via another transmission path.

Abstract: Provided are a portable terminal and method for multitasking for executing application programs of the portable terminal together with reception of digital broadcasting. The multitasking method of the present invention includes receiving and reproducing digital broadcast data requested by a user, and providing multitasking of executing at least one application program of the portable terminal according to a user's request during the reception and reproduction of the digital broadcast data.

Abstract: The extended range of optical data communication is enabled through the use of intermediary relay stations spaced fairly far apart. IRDA communicatiOn, as is well known, uses very short duration optical pulses to send data up to 1 Mbit/sec; this has the concomitant effect of minimizing LED duty cycle and preventing excessive heating. The invention uses a number of integrated pulses to represent a single bit instead of utilizing a one-to-one correspondence between pulses and bits. Processing software causes the transmitter to “stutter” or repetitively emanate the identical pulse representing a bit of information. Sufficient photons are thereby gathered at a receiver to reach a predetermined threshold. A tradeoff of the data transmission frequency in this invention is that as signal intensity drops by a factor of 100 when distance increases by a factor of 10 yielding a distance/intensity ratio of 1/10.

Abstract: An ultra wide band (UWB) communication system includes a channel filter bank to cover the 3.1 to 10.6 GHz band in channels having approximately equal bandwidth. A transmitter and a receiver may share the filter bank when the communication system is configured as a transceiver. The transmitter produces short duration, wide bandwidth RF pulses by triggering the impulse response of one or more of the filters of the filter bank. The impulse response is triggered by applying a very short duration time domain signal produced using a single pulse mixer and a step recovery diode circuit. The receiver uses a square-law detector to detect RF signals passed by the channel filter bank and the detected signals are further processed to extract a data signal and a confidence level in the data signal.

Abstract: A serial digital communication system includes a master device and a plurality of slave devices connected serially between the master device's output and input—thereby forming a closed chain. Each slave device transmits a predetermined number of PWM pulses to the device following it in the chain upon receipt of an end-of-transmission (EOT) signal from the device preceding it in the chain, and transmits an EOT signal when the transmission of its PWM pulses is completed. The master device transmits an EOT signal to initiate the transmission of PWM pulses from each slave device. Each slave device passively buffers PWM pulses received from the preceding device, such that PWM pulses are transmitted in one direction sequentially to the input of the master device via the intervening slave device.

Abstract: A digital modulator for driving a digital amplifier. The digital modulator has a subtractor which receives a digital input signal. A filter amplifier receives the output of the filter amplifier and is tuned to an idle frequency of the digital modulator. The digital modulator includes a delay element and a digital comparator. The digital comparator receives the output from the filter and applies it to the delay element. A feedback loop couples the output of the delay element to the subtractor.

Abstract: A digital PWM circuit is provided. One exemplary circuit includes a binary counter, an n-bit DAC and a comparator. The binary counter generates a plurality of binary signals in increasing and/or decreasing value. The DAC circuit generates ramp signals composed of a plurality of DC signals based on the binary signals. In another exemplary embodiment, reset circuitry is provided to control the frequency of the ramp signals.

Abstract: A dual phase pulse modulation (DPPM) decoder circuit processes a DPPM signal, which is in the form of a series of high and low pulses whose pulse widths represent successive groups of M data bits, so as to recover data carried by the signal. Each of the 2M possible data values of an M-bit group corresponds to one of 2M distinct pulse widths. Circuit blocks determine the width of each pulse by piping the DPPM signal through a short delay chain and inputting the delayed outputs and the non-delayed signal into AND logic gates, whose outputs are used to clock flip-flop registers. The registers are reset to a known state at the start of each signal pulse and toggled to an opposite state if clocked. The registered outputs are interpreted by logic to obtain the corresponding M-bit groups.

Abstract: A system and method for determining a minimum pulse width for a digital data stream is described herein. The minimum pulse width is used to infer the data rate for the digital data stream. A measuring cell is used to measure the pulse widths by utilizing RC time constants. The measuring cell comprises a capacitor whose voltage is related to the pulse width. This voltage is then transferred by the measuring cell to a measurement node which determines the minimum pulse width of all the transferred voltages for the plurality of pulses.

Abstract: A method for generating multiple high-resolution PWM signals in which software interrupts are introduced at predetermined intervals to generate multiple high-resolution PWM signals from a conventional microprocessor. The software determines the purpose of the interrupt in an interrupt subroutine. An interrupt occurs when a compare register equals the timer. Another interrupt occurs when the timer overflows. The interrupts are the key to generating the multiple high-resolution PWM signals.

Abstract: Disclosed is a method for modulating data for a polarity alternated pulse width code division multiple access (PAPW/CDMA) system and a method for measuring a distance between communicating equipments using the PAPW/CDMA. The method for modulating data includes the steps of multiplying CDMA signals inputted from multiple channels by a selected mask pattern, selecting the mask pattern among predetermined mask patterns that have the least peak value, truncation of multiplied CDMA signals according to a predetermined magnitude of levels to form level-number-reduced signals, converting the level-number-reduced signals to pulse width to generate modulated signals having a constant level, and alternately switching a starting polarity of pulses of the modulated signals between “high” and “low”.

Abstract: A channel evaluator acquires a change predicted value from a known symbol, and a compensator compensates for a first symbol using the change predicted value. A demodulator restores a portion corresponding to this symbol with another subcarrier. A replica generator acquires a transmission replica of the restored symbol. The channel evaluator performs complex division on the replica with the symbol to acquire an amplitude phase ratio. A detector compares the amplitude phase ratio with an amplitude phase ratio acquired immediately previously. In case where an elimination condition is satisfied, the detector disregards the amplitude phase ratio acquired currently and uses an immediately previous value instead, an averaging unit averages amplitude phase ratios to acquire a next change predicted value, and the compensator compensates for a next symbol using the change predicted value. Hereinafter, the sequence of processes is repeated.

Abstract: An apparatus and method for safely handling asynchronous shutdown of pulsewidth modulated output. A shutdown circuit controls asynchronous shutdown of a pulsewidth modulated stage to ensure that pulsewidth modulated signals of less duration than a minimum period does not occur at transition edges of the pulsewidth modulated signal, in which such short pulses may affect the proper operation of output circuitry.

Abstract: This invention extends the range of optical data of mobile device by trading speed for distance as well as integrating a plurality of pulses over time to define a single bit of information. The present invention uses a number of integrated pulses to represent a single bit instead of utilizing a one to one correspondence between pulses and bits. The present invention executes a range extender application which executes on the mobile device without any hardware modification to the mobile device. The range extender application causes the optical transmitter to “stutter” or repetitively emanate the identical pulse representing a bit of information. Sufficient photons are thereby gathered at a receiver to reach a predetermined threshold. A tradeoff of the data transmission frequency in this invention is that a signal intensity drops by a factor of 100 when distance increases by a factor of 10 yielding a distance/intensity ratio of {fraction (1/10)}.

Abstract: The invention concerns a method for connecting a device to a wireless network.

Abstract: A digital data modulator is coupled to a source of a digital data signal having a data bit period, and a source of an auxiliary data signal. An encoder encodes the digital data using a variable pulse width code having edges occurring in an interval within the data bit period. A pulse signal generator, generates respective pulses representing the edges of the encoded digital data signal. A carrier signal generator generates a carrier signal having carrier pulses corresponding to the respective pulses during the interval, and modulated by the auxiliary data signal otherwise. A digital data demodulator is coupled to a source of a modulated signal including successive bit periods, each having a first interval containing a carrier pulse, spaced relative to other carrier pulses, to represent a variable pulse width encoded digital data signal, and a second interval during which the carrier is modulated with an auxiliary data signal.

Abstract: Ternary weighted arrangements, for example, arrangements (delay circuits, devices, systems) including a variable delay determined on a ternary basis for use in testing set-up and hold times of a latch.

Abstract: A method and device for generating a constellation of Pulse Code Modulation (PCM) levels to represent digital data in a communication system. The constellation of Pulse Code Modulation levels are selected to have a total number of PCM levels and an upper power limit that optimizes noise performance. PCM levels are selected to increase the minimum spacing between PCM levels as great as possible while staying within the upper power limit for a constellation having a desired number of PCM levels. To minimize the power level of the selected constellation, constellation points are selected starting from PCM levels at linear values near zero to PCM levels at higher linear values. To improve noise performance, the number of occurrences of the minimum distance between PCM levels is also reduced without exceeding the upper power level. To reduce occurrences of the minimum distance between constellation points, PCM levels at the minimum distance from the previously selected PCM level may be skipped.

Abstract: A device for implementing a method for generating a pulse width modulated signal based upon a natural sampling technique is disclosed. First, a complex baseband signal is received by the device. Second, the device computes a first pulse edge vector and a second pulse edge vector as a function of the baseband signal. Third, the device computes a first set of natural sampling points as a function of the first pulse edge vector and computes a second set of natural sampling points as a function of the second pulse edge vector. These computations can involve one or more detections of a jump k&pgr; within the first pulse edge vector and/or the second pulse edge vector. Finally, the pulse width modulated signal is generated with pulse edges corresponding to the first set of natural sampling points and the second set of natural sampling points.

Abstract: A device for transmitting a pulse signal via a metallic line to a receiver end at which equalization is applied to the received pulse signal. The device includes a waveform adjustment unit which adjusts a pulse width in accordance with differences between characteristics of the metallic line and characteristics that are assumed for the equalization at the receiver end. The device further includes a transmission driver unit which transmits a pulse having the adjusted pulse width to the metallic line.

Abstract: A PWM (Pulse Width Modulation) circuit of the present invention includes a reference pulse sequence generating section for outputting a reference pulse sequence, an up-down counter, a trigger signal generating section for generating from an input signal a trigger signal for the up-down counter having a period which is a natural number multiple of one cycle the period of PWM, and a comparator for comparing the output of the up-down counter and the reference pulse sequence.

Abstract: A digital modulator for driving a digital amplifier. The digital modulator has a subtractor which receives a digital input signal. A filter amplifier receives the output of the filter amplifier and is tuned to an idle frequency of the digital modulator. The digital modulator includes a delay element and a digital comparator. The digital comparator receives the output from the filter and applies it to the delay element. A feedback loop couples the output of the delay element to the subtractor.

Abstract: The present invention relates to a merging network for multiple data streams comprising a pipelined butterfly network. The pipelined butterfly network comprises an input network for receiving a plurality of data streams of mutually constant widths, each data stream having logically related data bits carried on contiguous signal lines, a butterfly network containing suitably interconnected register and multiplexer means for rearranging the received data streams into a time-multiplexed constant-width output data stream, the output data stream having a width equal to or greater than the sum of the widths of the input data streams, and an output network for providing the output data stream interleaved to an output bus.