Abstract: A system for communicating between integrated circuits is disclosed. The system includes a driver having an input and an output. In response to a logic transition from a first logic state to a second logic state at the driver input, the driver output transitions from a low-power condition, to a transmitting condition, to the low-power condition. The system also includes a receiver having an input and an output. The receiver detects the logic state of the transmitting condition at the driver output and latches it to the receiver output after the driver output returns to the low-power condition. The system also includes a transmission line, which connects the driver output to the receiver input.

Abstract: In a communications system having a first modem pool for communicating with a second modem pool, each modem pool including a plurality of modems and having at least one NEXT cancellation filter, a method for modem wake-up including the steps of, during a first time period, a) activating at least one of the modems in the first modem pool, b) deactivating at least one of the modems in the second modem pool, for at least one target modem in the first modem pool c) activating the first modem pool NEXT canceller filter, d) measuring the NEXT transfer function for the target modem and at least one other disturber modem in the first modem pool, and, during a second time period, e) activating at least one of the modems in the second modem pool, f) deactivating at least one of the modems in the first modem pool, for at least one target modem in the second modem pool g) activating the second modem pool NEXT canceller filter, and h) measuring the NEXT transfer function for the target modem and at least one other disturb

Abstract: An efficient framing scheme is described for the transmission of frame overhead data in next generation ADSL modems. As a result of this new framing scheme, the available data rate for the transmission of payload data increases. High payload data rates and consequently wider reach of the ADSL modem are the most important performance requirements and customer care-abouts for ADSL modems. This application explains the new framing scheme in detail and provides examples for the computation of the framing parameters.

Abstract: Modem start-up delay reduced by measuring condition of communications line upon connection termination. Variation between termination and start-up line conditions determines if cold or warm start is required. Warm-start may use original condition descriptors. Condition represented by ambient noise, echo or spectral response of channel.

Abstract: An image processing apparatus capable of reducing noise contained in input image data. By determining whether or not, among the absolute values of the AC components of luminance Y, there is at least one value greater than a threshold value A, it is determined whether the components are effective edge components of the image or noise components. When it is determined that the components are effective edge components of the image, a suppress_flag is set to “0” so that a suppression process is not performed. When it is determined that the components are noise components, the suppress_flag is set to “1” so that a suppression process is performed. The present invention can be applied to a video camera for capturing an image of a subject.

Abstract: An adaptive pulse position modulated CDMA scheme for use in UWB communications systems is disclosed. A stream of input bits is encoded with spreading code sequence. The spreading code sequence consists of a number of code elements that may have one of two values. Each bit is encoded into a symbol consisting of a predefined number of chips, which are transmitted during a symbol period. Next, at least one code element is associated with each chip in the symbol. Then, an encoded pulse is generated in each chip. Each encoded pulse has a value determined by multiplying the data bit with the code value associated with the particular chip. The encoded pulse is then pulse position modulated by shifting the position of the pulse to a first position or a second position within the chip depending upon the encoded value of the pulse.

Abstract: A vehicle mounted DSRC apparatus is capable of achieving reduction in the size and cost thereof. The vehicle mounted DSRC apparatus includes an ASK data generation part 11, an I data generation part 21, a Q data generation part 22, a first band limiting filter 23A for band limiting I data and ASK data, a second band limiting filter 24 for band limiting Q data, an ASK low pass filter 12A for removing harmonic components from the ASK data, first and second low pass filters 25, 26 for removing harmonic components from QPSK data, an ASK modulator 13 for ASK modulating the ASK data, a QPSK modulator 27 for QPSK modulating the QPSK data, and a power amplifier 30 for amplifying output data of the ASK modulator 13 or the QPSK modulator 27 to a desired level thereby to output it to an antenna as an ASK modulated signal and a QPSK modulated signal.

Abstract: A modulation process for a digital transmission system having an error correcting code and determination of the number of bits to load on a transmission channel. The process judiciously associates a coder for introducing redundancy to the binary information, an interleaver for suppression the correlation to the encoded information and a labeling of the same based on a GRAY type coding in order to associate the said binary information with points of a constellation which is selected among a predetermined set of constellations. The process achieves a precise determination of the order and size of the constellation to utilize and, therefore, the computation of the bit loading as a function of the signal to noise ratio measured in reception and as a function of the bit error rate Pbit at the output of the receiver. The process is well adapted to the Multi Tone transmission system, and to the use of turbo codes.

Abstract: A system and a method for the transmission and reception of digital data wirelessly using acoustic tones comprises an encoder, a data interleaving system, an error correction system, and a decoder. The digital data is decoded by using in-phase and quadrature filters and through a score based function that determines the data that was most likely transmitted.

Abstract: A method and for optimizing bit rate throughput in a digital communication system is provided. The method includes establishing a relationship between signal to noise ratio and plural symbol rates for a particular constellation size. The method also includes determining noise power spectral density (N(f)), wherein N(f) is determined during a silent period of line probing; determining Xk(f), wherein Xk(f) is determined by turning on a remote station transmit signal, after N(f) has been measured and determining residual echo Ek(f), wherein Ek(f) is determined by turning on a central station echo canceller.

Abstract: The method of noise-immune information transmission of the present invention permits to increase the communication channel capacity without reducing the noise immunity of information being transmitted. In this method, informational digital samples are transmitted in the form of analog signal supplemented with a redundant information signal.

Abstract: Transition time of a data signal is controlled by applying different delays to the data signal and combining the delayed data signals. The transition time of the data output is determined by difference in delays applied to the data input and may be proportional to bit time of the bit clock. The data input may be applied directly to the delay elements or may be clocked by clock signals delayed by the delay elements. The delayed data is applied to parallel driver circuits. Supply voltage to the delay elements can be controlled to compensate for production and environmental variations. The supply voltage controller includes parallel delay elements of different delays and a phase comparator, the output of which controls the supply voltage applied to the delay elements.

Abstract: There is disclosed a technique in which any peaks above a threshold level are reduced, but not clipped, such that the effects of such peaks is reduced. Although the implementation of the technique preferably includes a clipping step, it is performed on the front-end rather than as the last step in the technique, such that the output signal is not a clipped signal. Any noise introduced by the clipping step, so-called clipping noise, is preferably filtered out of the useful frequency band of the signal.

Abstract: With the object of accurately reproducing, by means of a small-scale circuit, differences in propagation delay at antennas of received signals that are received as input by way of each of a plurality of receivers, frequency data generator 6 supplies frequency data that contain a frequency component that is synchronized in common to the plurality of receivers 2-1 to 2-n. At receiver 2-n, local oscillation signal generator 3-n, which is represented by a D/A converter, generates a local oscillation signal from frequency data that have been synchronized in common. The passing phase of a received signal that is outputted from antenna 1-n by way of receiver 1-n is thus fixed, and as a result, the phase difference of received signals that are received by DSP 8 by way of the plurality of receivers 2-1 to 2-n becomes the propagation delay difference of the received signals.

Abstract: An average tracking mechanism for a data communication receiver is provided. The average tracking mechanism of the receiver is connected to receive an input stream of data samples and is adapted to keep track of an average over a predefined number of most recently received data samples. The average tracking mechanism comprises a calculation unit that is adapted to calculate an approximate value of the average and a storage unit for storing calculated approximate values. The calculation unit is adapted to calculate the approximate value by retrieving a previously calculated approximate value from the storage unit and calculating a weighted sum of the retrieved approximate value and a current data sample. The average approximation technique may be used in a comb filter of a preamble detector in a WLAN receiver.

Abstract: An apparatus and method for compensating an imbalance of phase and gain between I-channel and Q-channel by using variable loop gains is disclosed. The apparatus includes: a phase error generator for generating a phase error signal by using the I-channel signal and the Q-channel signal; an average value calculator for calculating an average value of the phase error signal; a comparator for comparing the average value with a predetermined threshold; a selector for selecting a loop gain value among a set of loop gains based on the comparison result; a phase imbalance generator for generating a phase imbalance by using the selected loop gain value; and a compensator for compensating the Q-channel signal based on the phase imbalance.

Abstract: A method for demodulating a received digitally modulated signal subjected to multipath propagation impairment includes estimating the multipath propagation impairment of the received digitally modulated signal using a channel estimator, and estimating at least one symbol of the received digitally modulated signal using a symbol estimator. The at least one estimated symbol is adjusted based upon the estimated multipath propagation impairment to generate an estimate of the at least one symbol as impaired by the multipath propagation. At least one error signal is generated by comparing the estimate of the at least one symbol as impaired by the multipath propagation to the received digitally modulated signal. The at least one error signal is used for estimating remaining symbols to be demodulated and for refining the estimated multipath propagation impairment.

Abstract: To provide a clock and data recovery circuit which facilitates alteration of the frequency range and adjustment of characteristics.

Abstract: A coding method for modulating carrier signals with 16 different digital states (4 bit signals) possesses a high synchronicity robustness and an at least partially improved coding gain. The coding parameters are obtained by the following steps: a) using a 2 ASK/8 PSK coding; b) choosing a convolutional code and determining all possible code word sequences with the free distance of the convolutional code; c) producing possible mappings by allocating a partial quantity of the 2 ASK/8 PSK channel bits to subsets; d) choosing the mapping at which, after determination of the optimum radii of the two amplitudes for every possible mapping, the resulting minimum Euclidean distance takes a maximum value between two possible subset sequences code word sequence.

Abstract: A path storing circuit has path holding parts at a plurality of stages storing a survivor path and corresponding to times. A majority decision circuit receives output values of three delay circuits including the top and bottom delay circuits each receiving a selected output of a selector out of six delay circuits in the path holding part at the final stage and makes a decision by a majority.

Abstract: An apparatus and a method for symbol decoding of baseband data in a wireless communications network is disclosed, and specifically CCK subsymbol prediction and symbol demodulation that occurs at 5.5 Mbps or 11 Mbps. The apparatus is configured to demodulate or predict the data differently, depending on the modulation rate. If the data was modulated at 11 Mbps, the ?3 rotator is rotated through each of its possible phase values and symbol correlation takes four clock cycles to complete. If the data was modulated at 5.5 Mbps, ?3 is not rotated with a set value of 0 within the correlator architecture, thereby saving power and reducing symbol correlation and subsymbol prediction to a single cycle while in such transmission mode.

Abstract: The invention performs frequency estimation over both the burst preamble, during which known symbols are transmitted, and also during the burst's data packet, which is subsequent to the preamble and extracted by the local detector. During the preamble, an initial frequency estimate is obtained. This estimate is based on a time average of either phase or correlation samples. Atypical phase or correlation samples, attributable to detector symbol errors during the data packet, are detected and filtered, so as to avoid including the atypical samples in a time-averages used to provide the frequency estimate. In a first embodiment correlation samples are time averaged, and atypical correlation samples are suppressed prior to correlation time averaging. In a second embodiment, phase slope values are time averaged, and atypical values of phase slope are suppressed prior to phase slope time averaging.

Abstract: Method and apparatus for adjusting the frequency of a voltage controlled oscillator (VCO) at a receiver to synchronize the receiver with the transmitter by correlating a synchronization code channel with training sequences to estimate positive and negative offsets which are employed to estimate an error, which is then filtered. The filter output provides voltage controlling the VCO. The same technique may be employed to control a numeric controlled oscillator (NCO).

Abstract: A high-frequency signal receiver includes a variable gain amplifier for amplifying a high frequency signal input thereto, a local oscillator, a mixer for mixing a signal output from the variable gain amplifier and a signal output from the local oscillator, a filter for receiving a signal output from the mixer, a gain controller for outputting a voltage according to the signal output from the mixer; and a weighting circuit for weighting and summing a control voltage and the signal output from the gain controller for controlling the gain of the variable gain amplifier. The high-frequency signal receiver hence creates a small amount of signal error even when the input signal includes a large interference signal adjacent to a desired signal.

Abstract: A method of correctly estimating the frequency offset when the CPE modem has already acquired and is tracking the OFDM burst boundaries in an OFDM-based, wireless communication system. CPS data in an OFDM-based, wireless communication system is modulated as QPSK data in the training tones of the data burst. As long as some bursts have the CPS data modulation and some bursts do not have the CPS data modulation, the CPS data can be recovered. A slip results when there is a linear phase difference across the tones (after the FFT) between the current and the previous burst. This linear phase difference is generally taken care of by the channel estimation obtained using the pilot tones. This phase difference is however, now compensated for correct frequency offset estimation which occurs before the channel estimation and CPS decoding steps.

Abstract: A digitizing analog front end (DAFE) using mixed technology on a single substrate is described. SiGe BiCMOS technology is implemented for the semiconductor components, which include a low noise amplifier and an analog-to-digital converter. Micro Electro Mechanical System (MEMS) switches are used to change the filtering characteristics of several filters, including an anti-aliasing filter and a pre-select and anti-jamming filter.

Abstract: A method for reducing interference in a desired signal in a GSM communication system uses a finite-impulse-response filter for alternate linear equalization. The method includes a first step (300) of inputting a burst of data of a received waveform including interference from a channel of the communication system. A next step (302) includes training the finite-impulse-response filter with a set of symbols of specific quadrature phase, known a priori, in the burst of data of the received waveform. For example known real only and imaginary only symbols are alternatively selected from a midamble of the data burst. A next step (304) includes operating on the received waveform with the finite-impulse-response filter to alternately linearly equalize the burst of data to provide an estimate of the desired signal.

Abstract: In a transmitting apparatus 101, there are provided PLL circuit 601 for generating high-speed clock signals up to 2m times (m being a positive integer) from a basic clock signal, and a clock generating circuit 600 for generating a communication clock signal (S-CLOCK) and a reception timing signal (S-LATCH*) as independent clocks of any time length with using the generated high-speed clock signal as the smallest unit.

Abstract: A first transparent latch receives a first synchronised signal changing its logic state synchronously with respect to a clock signal. A second transparent latch receives a second synchronised signal output by the first latch. When the clock signal has a first logic state the first latch has a non-responsive state and the second latch has a responsive state, and when the clock signal has a second logic state the first latch has the responsive state and the second latch has the non-responsive state. The change in logic state of a third synchronised signal output by the second latch is guaranteed to occur in a particular half-cycle of the clock signal, irrespective of process/voltage/temperature (PVT) variations of the circuitry.

Abstract: A timing recovery circuit and related method is disclosed. The timing recovery circuit encompasses a converter, an interpolator, a phase error detector, an adjustment circuit, and a calculation circuit. The converter samples an input signal to generate an intermediate signal carrying samples of the input signal, while the interpolator inserts an interpolating sample into the intermediate signal in response to a control value to generate an output signal. The phase error detector outputs a phase error of the output signal. The adjustment circuit updates an over-sampling ratio according to a pair of first and second thresholds, and a counting value adjusted in response to the phase error and a median reference value. Finally, the calculation circuit derives the control value from the updated over-sampling ratio, and transferring the control value to the interpolator.

Abstract: A communication system is provided in which normal communications can be ensured even upon a loss of synchronization on a part of transmission paths configuring a network. The system is to perform data communications within a network configured by a plurality of devices. A synchronization detecting section detects a loss of synchronization for data transmission between devices connected to each other via the network. Upon detection by the synchronization detecting section of the loss of synchronization, a control information retaining section and a switching section included in the first device cause a connection with the second device to be cut off, and then again cause a connection with the device. Upon connection caused by the switching section between the devices, a connection processing section 16 performs a connecting process for enabling data communications between these devices.

Abstract: A method and arrangement of passing data from a source clock domain to a non-synchronous receive clock domain are provided. A first processing circuit, located in the source clock domain, links write-address information with the data, and a clock generator generates a transmit clock signal in the source clock domain synchronous with a source clock. The first processing circuit transmits the clock signal and the data with the linked write-address information to a second processing circuit in the receive clock domain. In the receive clock domain, the second processing circuit writes the data at an address designating a storage element corresponding to the linked write-address information. The second processing circuit clocks the data into the storage element synchronous with the accompanying transmit clock signal responsive to a write enable signal from the source clock domain, and reads the data out of the storage element synchronous with a receive domain clock.

Abstract: A digital clock manager is provided. The digital clock manager generates an output clock signal that causes a skewed clock signal to be synchronized with a reference clock signal. Furthermore, the digital clock manager generates a frequency adjusted clock signal that is synchronized with the output clock signal during concurrence periods. The digital clock manager includes a delay lock loop and a digital frequency synthesizer. The delay lock loop generates a synchronizing clock signal that is provided to the digital frequency synthesizer. The output clock signal lags the synchronizing clock signal by a DLL output delay. Similarly, the frequency adjusted clock signal lags the synchronizing clock signal by a DFS output delay. By matching the DLL output delay to the DFS output delay, the digital clock manager synchronizes the output clock signal and the frequency adjusted clock signal.

Abstract: A technique for performing a frequency error correction process is provided that may be used in receivers of wireless local area network systems. The technique comprises a three-phase process generating a frequency approximation value based on a frequency error estimate, starting a channel estimation process that uses the generated frequency approximation value, refining the generated frequency approximation value, and compensating a frequency error using the refined frequency approximation value. Further, a corresponding integrated circuit chip and an operation method are provided. Using the technique for performing a frequency error correction process may provide high reliability, high precision and improved operation speed.

Abstract: A method for providing a nuclear fuel includes forming a uranium-molybdenum alloy that provides an enhanced reactivity in research, test and radioisotope production nuclear reactors. In this uranium-molybdenum alloy, the uranium is enriched in the isotope 235-U, while the molybdenum is depleted in the isotope 95-Mo. The thus obtained enhanced reactivity can have at least two advantages, depending on the exact use of the fuel element: a requirement for less uranium in the fuel and the use of the fuel elements during a longer period in the reactor.

Abstract: In a method and device for, generating computed tomography images of a periodically moving organ of an organism, the organ having regions with rest phases and movement phases and the rest phases of different regions ensuing at different points in time, an x-ray source is moved around the body of the organism to be examined to generate projections serving for the image generation during at least one rotation of the x-ray source around the subject to be examined and during a duration that is at least equal to a period of the motion. The projection data are analyzed as to whether the data were acquired during a rest phase or movement phase of a respective region of interest of the organ, and an image of the organ is reconstructed using only data acquired during a rest phase of a respective region of interest of the organ.

Abstract: Projection data are obtained by using a method for imaging by rotating the first imaging system having an X-ray generating unit 1a and the second imaging system having an X-ray generating unit 1b. The obtained projection data are subjected to a reconstruction process to generate X-ray image data. In this case, a relative angle ?0 formed between the imaging systems is setup according to a palmic period T0 of a subject and a rotation velocity Vr of the imaging systems. Thus, the projection data from more directions at a predetermined palmic time-phase are collected without overlapping.

Abstract: The invention relates to a computerized tomography method, in which an examination area is scanned radiographically along a helical trajectory by a conical beam. The radiation transmitted through the examination area is measured by means of a detector unit, wherein the absorption distribution in the examination area is reconstructed exactly or at least quasi-exactly from these measured values. Reconstruction uses redundant measured values and comprises derivation of the measured values from parallel rays of different projections, integration of these values along ?-lines, weighting of these values and back-projection.

Abstract: A method for scanning an object to reduce image degradation includes scanning the object in a helical mode using a multi-slice CT imaging system having a plurality of detector arrays arranged along a z-axis direction and a radiation source having a beam focal spot. The method further includes wobbling the focal spot of the radiation source in the z-axis direction during the scanning to selectively preferentially illuminate individual detector arrays through the scanned object for each view. Data is collected from each detector array for each view only when the detector array from which data is being collected is selectively illuminated.

Abstract: A blur compensation apparatus for X-ray image of an object to be examined used for a medical X-ray imaging apparatus, which has an X-ray generator and an X-ray imaging device opposite to the X-ray generator, said X-ray generator and said X-ray imaging device interposing therebetween said object held by an object holding means, wherein a sensor means for detecting blur movement of said object is provided near an objective projection position on said object holding means, and wherein a blur compensation process is executed for the X-ray image obtained by said X-ray imaging device, based on a positional change information which is calculated from a detection signal detected by said sensor means during X-ray radiography, said positional change information being the positional change amount with respect to said objective projection position relative to a reference position previously specified on said object holding means.

Abstract: A method for obtaining data includes scanning an object with radiation to collect projection data using an imaging system having a detector array with detector cells and a post-patient collimator, wherein the post-patient collimator has plates having non-uniform thicknesses. The method further includes applying a correction to the projection data to shift an effective center of at least some of the detector cells to compensate for the non-uniform thicknesses of the collimator plates.

Abstract: A calculating device 10 for calculating the concentration of elements contained in a sample 13 based on the FP method is provided. The calculating device 10 is operable to assume a concentration of unmeasured elements as far as unmeasured elements, of which fluorescent X-rays are not measured, are concerned, and, also, to utilize, in place of the secondary X-rays emanating from the unmeasured elements contained in the sample, scattered X-rays of the primary X-rays at least equal in number to the number of the unmeasured elements, of which concentrations are assumed, and including scattered X-rays of different wavelengths before they are scattered from the sample.

Abstract: An apparatus and method for irradiating a product or product stack with a relatively even radiation dose distribution is provided. The apparatus comprises a radiation source, an adjustable collimator, a turn-table capable of receiving a product stack and a control system capable of adjusting the adjustable collimator to vary the geometry of the radiation beam as the product stack is rotated in the radiation beam. Also disclosed is the modulation of the radiation beam energy and power and varying the angular rotational velocity of the product stack in a radiation beam to achieve a low dose uniformity ratio in the product stack.

Abstract: A monochromator to be used in an X-ray device having an X-ray source is formed by a crystal for spectral restriction of X-rays produced by the X-ray source. The monochromator includes a positioning device that can move the crystal so that it changes the spectral composition of the X-radiation. The crystal can be moved so that it changes the angle between an X-ray path and the crystal, or so that the crystal is removed out of X-ray path or returned into it.

Abstract: In an operating method for a medical installation, in particular an x-ray installation. In activation state of the medical installation, a control and evaluation device determines, upon input of a control command, a useful image of a subject. For this purpose, the control and evaluation device receives raw image of the subject acquired by a detector in a first detector mode, and determines the useful image therefrom on the basis of correction data. In a waiting state of the medical installation, the control and evaluation device updates the correction data for the first detector mode repeatedly after the expiration of a basic time interval since the last driving of the detector. For this purpose, the control and evaluation device receives raw data acquired by the detector and uses it to update the correction data.

Abstract: An electron emitter assembly and a method for generating an electron beam are provided. The electron emitter assembly includes a laser configured to emit a first light beam and a second light beam. The electron emitter assembly further includes a mirror configured to move to a first operational position to reflect the first light beam toward a first region of a photo-cathode. The mirror is further configured to move to a second operational position to reflect the second light beam toward a second region of the photo-cathode. The photo-cathode is configured to emit a first electron beam when the first light beam contacts the first region and to emit a second electron beam when the second light beam contacts the second region. The electron emitter assembly further includes an anode configured to receive the first and second electron beams from the photo-cathode.

Abstract: An X-ray CT apparatus capable of imaging a subject based on X-rays of multiple energy levels while using an ordinary X-ray detector includes an X-ray tube which generates X-rays from multiple focal points of different 3-dimensional positions sequentially on a time-division basis, a plurality of filters which implement the filtering individually for the X-rays generated individually from the focal points, a collimator which equalizes the irradiation range of the X-rays generated individually from the focal points, collection means which collects projection data of multiple views of a subject of imaging for the X-rays generated individually from the focal points, and reconstruction means which reconstructs an image based on the projection data. The anode of the X-ray tube has multiple impingement portions where electrons released by the cathode impinge at multiple positions on the trajectory of electrons sequentially on a time-division basis.

Abstract: A cooled radiation emission device has an enclosure in which X-rays are produced. In the enclosure, there is a cathode, an anode situated facing the cathode and rotating on a shaft, and a fixed anode shaft support. The support includes a holding chamber, the shaft of the anode being held in the chamber. The cooling of the tube uses a gallium-indium-tin liquid alloy flow through the anode shaft. This alloy is a conductor of heat and electricity. At the same time as the lubrication of the bearings and the electrical powering of the anode, it provides for cooling of the anode.

Abstract: A method for operating a telecommunication network in exceptional situations includes defining a group of connections of the network, the connections each having a respective terminal connected thereto, the connections being dialable via individual network identification numbers. The connections are blocked for calls to be allocated to the connections. Lines leading to the connections are rerouted via a server connected to the network. The server is used to organize the calls.

Abstract: A voice mail method screens calls made by a calling subscriber (10) to a called subscriber (20) which is unavailable (or otherwise screening calls). The screening method determines (110) whether the called subscriber (20) has a voice mail screening feature. An internet protocol multi-media system (50) receives the call from the called subscriber (114). The internet protocol multi-media system then transfers call control to a voicemail screening server which plays subscriber (20) the beginning of the voicemail message being left by subscriber (10) and offers to-route the call back to the called subscriber (20). The called subscriber then indicates via a short code whether the called subscriber will accept the call (124).