Abstract: An autodetect circuit for a router system includes an interface to two bidirectional serial links, an input multiplexer circuit coupled to one side of the link interface for receiving input data signals and clock signals, a receiver coupled to the input multiplexer circuit and to a receive FIFO, a state machine coupled to the receiver, a transmitter coupled to the state machine, a transmit FIFO, and to the other side of the link interface for transmitting output data, and a counter coupled to the state machine for controlling the input multiplexer circuit. The autodetect circuit determines which of the two links “A” or “B” is active and available for transmission. The counter is incremented whenever a link reset occurs. When the count reaches a predetermined maximum count value, a port enable signal is toggled from the default “A” link to the “B” link. When one port is enabled, any activity on the other port is ignored.

Abstract: A wireless communication system can comprise two or more antennas that interfere with one another via free space coupling, surface wave crosstalk, dielectric leakage, or other interference effect. The interference effect can produce an interference signal on one of the antennas. A cancellation device can suppress antenna interference by generating an estimate of the interference signal and subtracting the estimate from the interference signal. The cancellation device can generate the estimate based on sampling signals on an antenna that generates the interference or on an antenna that receives the interference. The cancellation device can comprise a model of the crosstalk effect. Transmitting test signals on the communication system can define or refine the model.

Abstract: A system and method for enhancing the performance of a wireless communication system are disclosed. For example, a method for enhancing the performance of a wireless communication system is disclosed, which includes the steps of receiving a signal including a first plurality of sub-bands, calculating a plurality of channel quality values, each channel quality value associated with a respective sub-band of the first plurality of sub-bands, conveying the plurality of channel quality values to a processing unit associated with a transmitter unit that transmitted the signal, determining the highest channel quality value from the conveyed plurality of channel quality values, determining a cyclic delay value associated with the highest channel quality value, and applying the cyclic delay value to a second plurality of sub-bands.

Abstract: A method and apparatus for wireless transmission from a mobile unit to a base station includes multiplexing a pilot signal and a data signal, wherein the data signal operates at a data rate by splitting the data signal into a plurality of data streams; applying a pilot gain to the pilot channel, wherein the data gain and the pilot gain are a function of the data rate; and combining the plurality of data streams and the pilot signal into a subset of sub-carriers. The subset of sub-carriers are transmitted using Discrete Fourier Transform Spread OFDMA.

Abstract: In accordance with an embodiment of the present invention, a novel system and method for MMSE channel estimation are provided that take synchronization errors, either intentional or unintentional, into account during the channel estimation process. The proposed channel estimation in accordance with the present invention improves the noise averaging capability and takes advantage of channel correlation fully by removing the effect of synchronization errors during the estimation process.

Abstract: Detecting Null symbols in a video data frame comprises sending OFDM symbols through a sliding windowed correlation process having a correlation window length proportional to a cyclic prefix length and a delay equal to a FFT size of the symbols, wherein output peaks of the process occur where two similar portions of the symbols coincide; checking peaks in windows sized equal to a duration of a symbol; determining whether the peaks are located in the middle of the windows; determining whether a shift has occurred in the location of the peak of a current window compared to in a second immediately previous window; determining whether the peak in a first immediately previous window is weak compared to that in a second immediately previous window; and declaring that a Null symbol exists in the first previous window when the shift has occurred and the determination of a weak peak exists.

Abstract: The disclosure relates to a method for decoding a received signal comprising symbols which are distributed in space and time with the aid of a space-time coding matrix, comprising a space-time decoding stage and at least two iterations, each of which comprising the following sub-stages: diversity pre-decoding, the opposite of diversity pre-decoding carried out when the signal is emitted, providing precoded data; estimation of symbols forming said signal on the basis of said pre-decoded data, providing estimated symbols; diversity preceding identical to diversity preceding carried out during emission, applied to the estimated symbols in order to provide an estimated signal.

Abstract: A mobile communication system and method for transmitting signals through a plurality of transmission antennas by space-time coding the signals. The signals are transmitted using a low density parity check code. A lifting low density parity check matrix is formed by expanding values of elements in a low density parity check matrix with a sub-matrix corresponding to a number of the transmission antennas. The signals to be transmitted are coded using the lifting low density parity check matrix. Thereafter, the coded signals are serial/parallel converted and transmitted through the transmission antennas.

Abstract: A MIMO wireless system includes a transmitter having a parser that parses a bit stream into multiple spatial data streams and multiple interleavers corresponding to the multiple spatial data streams, where each interleaver interleaves the bits in the corresponding spatial data stream by performing multiple column rotations and row rotation, to increase diversity of the wireless system. The MIMO wireless system also includes a receiver that has deinterleavers that deinterleaves spatial bit streams transmitted by the transmitter.

Abstract: A transmitter beamforming technique for use in a MIMO wireless communication system determines a partial description of a reverse channel without determining a full dimensional description of the reverse channel. A correction matrix is developed from the partial description of the reverse channel and a description of the forward channel. The correction matrix is used to process signals to be transmitted via the forward channel, and a steering matrix is used to perform beamforming in the forward channel.

Abstract: The invention relates to a method of transmitting digital data exhibiting a rate T by means of a frequency modulator able to modulate as a function of the data, a central carrier frequency f0 at a first frequency value f0+¼T and/or a second frequency value f0?¼T. It comprises the step consisting in modulating the carrier frequency from one of the frequency values to the other during a time interval T, via successive frequency stages.

Abstract: A method for generating a modulated carrier signal with reduced bit error rates based on a plurality of data symbols. A plurality of data symbols are received, and a digital input signal is generated based on the plurality of data symbols. The digital input signal are filtered to produce a digital output signal including a phase characteristic. The phase characteristic of the digital output signal remains close to the desired symbol phase for substantial portion of the symbol period. A carrier signal is modulated using the digital output signal to produce the modulated carrier signal.

Abstract: A method and system are provided for transmitting data in a multiple-input multiple-output (MIMO) communication system. A receiver sets the number of sub-streams of each column of a preceding matrix with respect to all precoding matrices of channels formed between the receiver and a transmitter and measures channel states with respect to sub-stream combinations whose number is equivalent to the number of set sub-streams. The receiver transmits data according to channel states to the transmitter after measuring the channel states with respect to the sub-stream combinations and antenna combinations representing sub-streams used upon data transmission of all the precoding matrices.

Abstract: A wireless communication method of repetition system and the like for ensuring that when the same data symbols are combined, a diversity gain is achieved. In a step (ST 420), a data symbol placing part (105) decides destination places of respective replicated data symbols (S1-S4) such that the same data symbols are not placed at destination place numbers (7,8) of data symbols that exhibit poor channel estimation precisions. In a step (ST 430), the data symbol placing part (105) places, in accordance with the decision in the foregoing step (ST 420), the four data symbols (S1-S4), which are received from a repetition part (102), in one frame received from a channel estimation error predicting part (104).

Abstract: Techniques to process data for transmission in a time division duplexed (TDD) communication system. In one aspect, the frequency response of a forward link is estimated at a base station based on reverse link transmissions (e.g., pilots) from a terminal. Prior to a data transmission on the forward link, the base station determines a reverse transfer function based on the pilots transmitted by the terminal, “calibrates” the reverse transfer function with a calibration function to derive an estimate of a forward transfer function, and preconditions modulation symbols based on weights derived from the forward transfer function. In another aspect, the terminal estimates the “quality” of the forward link and provides this information to the base station. The base station then uses the information to properly code and modulate data prior to transmission such that the transmitted data can be received by the terminal at the desired level of performance.

Abstract: Architectures including digital outphasing transmitters. Digital signal generation circuitry generates at least two base-band sinusoid signals. Bandpass modulation circuitry is coupled to receive the base-band sinusoid signals and generates at least two modulated digital signals. Power amplifiers are coupled to receive the modulated digital signals to amplify the modulated digital signals. The amplified modulated signals are combined and transmitted.

Abstract: Digital predistortion system, methods and circuitry for linearizing a non-linear element using a multiply partitioned architecture that first addresses long or “memory” effects, and separately addresses shorter duration effects. These blocks or circuits are operated with the non-linear element to provide a highly linear system. A first or long predistortion block receives a baseband signal input and includes a plurality of parallel memory blocks each including a programmable linearity, a digital filter, summers, multipliers and multiplexers with control signals for configuring the blocks to form filters of different types. A second or short predistortion block is coupled to the long predistortion block and comprises a generalized Nth order polynomial filter coupled to a programmable linear equalizer. The first predistorter block compensates for effects of a longer duration, and the second predistorter block compensates for effects of a shorter duration.

Abstract: A MIMO communication system implements an interleaver design with multiple encoders for more than two transmit antennas for high throughput WLAN communication systems. Multiple encoders are utilized in the transmitter and multiple decoders are utilized in the receiver, wherein each encoder operates at lower clock speed than would be necessary with a single encoder. In conjunction with using multiple encoders, a modified interleaving function for each spatial stream processing allows fully exploring the diversity gains. The provided interleaving function is suitable for transmitter architectures with multiple encoders. Similarly, a modified de-interleaving function is provided that is suitable for receiver architectures with multiple decoders.

Abstract: A frontend module includes a first and a second input for transmitted signals, an amplifier, a bypass line for bypassing the amplifier, an output and a switching unit. The switching unit either forms a signal path between the first input and the output, in which the amplifier or the bypass line is coupled, or forms a signal path between the second input and the output, in which the amplifier or the bypass line is coupled.

Abstract: A DSP tuner, which is equipped with an A/D converter and a digital signal processing part, is provided to the receiving parts of an in-vehicle equipment and a portable equipment that constitute an in-vehicle equipment remote control system. The A/D converter quantizes analog input signals received by receiving antennas and converts them into digital values. The digital signal processing part always appears, and removes as a noise a frequency band of which spectrum hardly change within a predetermined time period. Moreover, the digital signal processing part sets a frequency band with a comparatively large spectrum change as an FSK modulation signal corresponding to code contents, and outputs binary data corresponding to the frequency band as a code signal.

Abstract: A proposed spread spectrum signal receiver includes a radio front-end unit and a processing unit. The radio front-end unit, in turn, has an antenna, a digitizing circuit and a primary buffer unit. The antenna is adapted to receive radio signals (SHF) from a plurality of signal sources, and the digitizing circuit is adapted to downconvert and filter the received signals (SHF), and generate sample values (SBP-D) thereof. The primary buffer unit is adapted to temporarily store the sample values (SBP-D) from the digitizing circuit and allow the processing unit to read out a first set of stored sample values (SBP-D) contemporaneously with the storing of a second set of sample values (SBP-D) in the primary buffer unit. The processing unit is adapted to receive the sample values (SBP-D) from the primary buffer unit, and based thereon, produce position/time related data (DPT).

Abstract: A receiver having a circuit configurable to function as a low-noise amplifier or a calibration source and having at least one circuit element that is shared between these two circuit functions. Advantageously, the shared circuit element saves at least the amount of die area that would have been taken by a second instance of that circuit element.

Abstract: Multi-carrier modulation fiber optic systems constructed using a series of electrical carriers, modulating the data on the electrical carriers and combining the carriers to form a wideband signal. The wideband signal can then be intensity modulated on a laser and coupled to a fiber optic channel. A receiver may then receive the laser signal from the fiber optic channel and convert it into an electrical signal. Multi-carrier modulation may be applied to existing fiber channels, which may be of lower quality. Existing fiber channels may have characteristics which prevent or restrict the transmission of data using intensity modulation at certain frequencies. An adaptive multi-carrier modulation transmitter may characterize an existing fiber optic channel and ascertain the overall characteristics of the channel. The transmitter and receiver can then be configured to use various bandwidths and various modulations in order to match the transfer characteristic of the fiber channel.

Abstract: Systems and methods for determining a slicing level which is used as a threshold to determine whether timeslots of an incoming data signal contain ones or zeros. The method of one embodiment comprises receiving a data signal, identifying a maximum level of the data signal, identifying a minimum level of the data signal, determining an average of the minimum and maximum levels, and then using the average of the minimum and maximum levels as a slicing level to identify bits of a data packet embodied in the data signal.

Abstract: Aspects of a method and system for signal phase variation detection in communication systems are presented. Aspects of the system may enable detection of phase change between a current received symbol, and one or more previous received symbols. Based on the phase change a channel estimation filter bandwidth may be selected for despreading and/or descrambling one or more subsequent received symbols. In addition, a decision may be made as to whether the subsequent received symbols are to be received based on a closed loop system, or based on an open loop system.

Abstract: A phase-shift keying (PSK) receiver includes a carrier wave generator generating a carrier wave, an extracting unit extracting an in-phase component I and a quadrature component Q from a received signal on the basis of the carrier wave and the received signal, a comparator comparing the in-phase component I and the quadrature component Q extracted from the received signal to a predetermined threshold values respectively and acquiring 1-bit digital signals corresponding to the in-phase component I and the quadrature component Q respectively; and a BPSK demodulator demodulating the received signal using a binary phase-shift keying (BPSK) scheme on the basis of positional relationship on I-Q constellation between the 1-bit digital signals corresponding to the in-phase component I and the quadrature component Q acquired by the comparator.

Abstract: The present invention discloses a burst detection apparatus and method. The burst detection apparatus of the present invention comprises a power module, a soft-metric RMS module, and a quality determination module. The bust detection method comprises the following steps: At first, a reciprocal value of the received signal's power is calculated. Next, a RMS value of the soft-metrics according to the received signal is computed. At last, a product of the reciprocal value and the RMS value is compared with a given threshold value to generate a Boolean outcome as a quality determination decision. If the product of these values is lower than the given threshold value, it means the received signal is believed as noise; otherwise, it is believed as the real signal.

Abstract: A GPS receiver architecture is disclosed having digital correlation processing in faster than real-time, which is achieved by storing signal samples into a memory in real-time at a first rate and reading packs of stored samples at a second higher rate. For mitigating cross-correlation interference from the strong signal to reception of weak ones, a group of compensator blocks is introduced. A method of interference waveform reproducing is disclosed that compensates influence of stronger signal over long coherent accumulation intervals, not complicating processing of the strong signal over shorter coherent accumulation intervals. Search bins corrupted by under-compensated interference are pre-calculated and discarded.

Abstract: Signal decoding apparatus, signal decoding method, program, and information record medium are provided and can accomplish not only high-speed and high-capacity communication, but high-accuracy decoding. An initial channel estimation section 31 estimates an initial channel with a pilot symbol added at the beginning of each packet. After a replica of a transmission symbol is generated, for a reception signal vector, CCI components for L transmission antennas are generated. A CCI canceller 33 removes the CCI components from the reception signal vector. After the reception symbol vector from which the CCI components had been removed has been obtained, a division device 34 obtains an instantaneous estimation value. An update condition determination section 35 detects deterioration of a channel response accuracy based on a threshold value. An instantaneous estimation value whose SNR has been determined to be insufficient is discarded.

Abstract: A system and method is disclosed for providing a robust ultra low power serial interface with a digital clock and data recovery circuit for power management systems. In one advantageous embodiment a digital clock and data recovery circuit of the invention comprises a quadruple phase clock generator circuit that generates four shifted clock signals, a decision logic circuit, a state detector circuit, and an edge detector circuit. The detected edges of data signals are used to latch the state of the four shifted clock signals. The state detector circuit selects a stable clock signal among the four shifted clock signals for use as a recovered clock signal and synchronizes the recovered clock signal at a center of the data signal. The selected recovered clock signal remains available until another data signal transition is detected.

Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.

Abstract: An audio processor is disclosed and includes a sample rate converter and a digital phase-locked-loop module in communication with the sample rate converter. The sample rate converter includes a plurality of digital filters, and the digital phase locked loop module includes a phase accumulator having an initialization value determined based at least partially on a filter sequence address associated with the plurality of filters.

Abstract: A system and method of performing re-synchronization for a Digital Video Broadcasting over Handheld (DVB-H) receiver comprises performing a time division multiplexing (TDM) data burst transmission sequence on bits of data received by the DVB-H receiver; performing a data bit re-synchronization sequence on the DVB-H receiver; and reducing a re-acquisition time at every stage of the data bit re-synchronization sequence, wherein the reducing process results in a reduction in the time to perform the re-synchronization for the DVB-H receiver, wherein the reduction in the time to perform the re-synchronization for the DVB-H receiver is greater than one-half of the time required to perform the re-synchronization for the DVB-H receiver absent the reducing of the re-acquisition time at every stage of the data bit re-synchronization sequence.

Abstract: A system and method of performing re-synchronization for a Digital Video Broadcasting over Handheld (DVB-H) receiver, wherein the method comprises performing a time division multiplexing (TDM) data burst transmission sequence on bits of data received by the DVB-H receiver; performing a data bit re-synchronization sequence on the DVB-H receiver; removing an on-chip timer and internal state registers in the DVB-H receiver; and allowing the DVB-H receiver to power off in between receipt of data bursts. Preferably, the removing process reduces the time to perform the re-synchronization in the DVB-H receiver. Preferably, the data bit re-synchronization sequence comprises performing an automatic gain control (AGC) lock process; performing a mode and guard detecting process; performing a frequency offset estimation process; performing a transmit parameter signaling (TPS) detection process; performing a timing and carrier loop lock process; and performing an equalizer delay process.

Abstract: An apparatus and method of aiding synchronization between a master transceiver and a slave transceiver is disclosed. The method includes the master transceiver transmitting data signals that are received by the slave transceiver. The slave transceiver locks a slave clock to the data signals with a slave phase-locked loop. The slave transceiver transmits slave clock information to the master transceiver.

Abstract: A system including asymmetric control of high-speed bidirectional signaling includes a slave device and a master device that is coupled to the slave device via a plurality of bidirectional data paths, for example. The master device may control data transfer between the master device and the slave device. More particularly, the master device may adaptively modify transmit characteristics subsequent to adaptively modifying receiver characteristics based upon information received from the slave device via one or more unidirectional data paths.

Abstract: A NICAM system includes a NICAM deframer, a FIFO buffer and a symbol rate conversion (SRC) unit. The NICAM deframer obtains multiple deinterleaved symbols according to a strobe signal and a data signal in each timing and expands the deinterleaved symbols to corresponding multiple pulse code modulation (PCM) symbols. The FIFO buffer temporarily stores the symbols and outputs the PCM symbols at a local timing, rate. The SRC unit determines whether a SRC function is enabled according to the statuses of the symbols in the FIFO buffer every a constant time interval. When the SRC function is enabled, the SRC unit interpolates the PCM symbols to obtain multiple new PCM symbols and outputs the new PCM symbols at the local timing rate.

Abstract: Methods and systems for imaging a patient are provided. The method includes scanning a patient and acquiring a plurality of frames of cine computed tomography (CT) images during one complete respiratory cycle. In one embodiment, a method is provided that includes selecting a value for each pixel that represents the maximum density measurement for the pixel throughout the cine acquisition. In one embodiment, an attenuation correction image of a volume of interest is constructed by weighting a combination of the maximum pixel intensity value and an average pixel intensity value. Undesirable motion artifacts can be removed from positron emission tomography (PET) images by utilizing the CT attenuation correction image.

Abstract: An X-ray tomograph comprises an X-ray generator having a function of moving the focal position and radiating X-rays toward a subject, an X-ray image receiving element for receiving transmission images created by X-rays radiated from the X-ray generator, and an image processing section for creating a tomographic image by processing the transmission images of the subject received by the X-ray image receiving element. A stereoradioscopic image constructing equipment comprises the X-ray tomograph and a stereoradioscopic image constructing section for creating a stereoradioscopic image by subjecting the created tomographic images to image processing. By using the X-ray tomograph, a tomographic image can be created without providing any high-precision movable mechanism, and a tomographic image of even a soft subject can be correctly created.

Abstract: An X-ray imaging apparatus includes an X-ray imaging unit, rotating unit configured to rotate a subject about an axis of rotation relative to the X-ray imaging unit, supporting unit configured to support the subject, and a limiting unit configured to limit the range in which the X-ray imaging unit is moveable along the axis of rotation depending on the position of the supporting means relative to the axis of rotation.

Abstract: A medical device has a compression plate for compression of a subject and/or a subject table for placement of a subject, and at least one radiation source that emits electromagnetic radiation. The compression plate and/or the subject table can be heated by the electromagnetic radiation radiated by the at least one radiation source.

Abstract: A sample cell for an analysis instrument, having an outer body forming a sample reservoir therein; a directional fill valve disposed in an upper end of the outer body and forming an upper end of the sample reservoir, the fill valve for accepting a sample during filling, and preventing sample leakage while providing venting after filling; and a film covering a lower end of the outer body, and forming a bottom end of the sample reservoir, the film for presenting the sample to an analysis focal spot of the analysis instrument. The disclosed sample cell is especially suited for an x-ray analysis engine having a focal spot requiring alignment with the sample in the sample cell. At least one x-ray optic may be disposed in an excitation and/or detection path, requiring alignment to the focal spot, in e.g., a WDXRF or EDXRF system.

Abstract: A system to analyze the geometry of a radiation treatment apparatus, software, and methods are provided. The system includes an apparatus having a rotating assembly and a trackable body or plurality of trackable bodies, to mark a location of a preselected portion of the rotating assembly. The system also includes a trackable reference fixture and can include a constant orientation trackable body. A determiner determines the position and/or orientation of the trackable bodies, the trackable reference fixture, and constant orientation trackable body. The determiner then determines the geometry of the treatment apparatus to analyze a coordinate system used by an operator. The determiner can have a memory and geometry analyzing software stored in the memory to analyze the treatment apparatus geometry.

Abstract: A highly compact, high-performance volumetric imaging system is proposed, that is integrated with a multi-source Cobalt-60 gamma irradiator for high throughput, high accuracy and minimally invasive fractioned treatments of intracranial, orbital and head-and-neck targets.

Abstract: An X-ray generator uses a high electrical field generated when a hemimorphic crystal is heated or cooled. The crystal may be lithium niobate polarized in one direction. An X-ray target is placed inside a housing inside which a vacuum is maintained. A tungsten line containing thorium is placed between the crystal and the target. When the crystal is heated or cooled by a Pelletier element, an intense electrical field is generated around the crystal. Thermoelectrons released from the tungsten line accelerate as a result of the electrical field and collide with the X-ray target. The X-rays released at this time radiate through a beryllium window exteriorly of the housing. Intense X-rays are generated without using large scale equipment, such as a high voltage power source.

Abstract: A radiation image capturing apparatus that includes a radiation conversion panel comprises an input device for inputting a first distance from the position of the panel to a position serving as a reference position for a subject, a distance measuring unit for measuring a second distance from the radiation source to the panel, a first radiation field calculating unit for determining a radiation field at the position of the panel based on setting information of the radiation source and the second distance, a second radiation field calculating unit for determining a hypothetical radiation field at the reference position of the subject based on the setting information of the radiation source, the first distance, and the second distance, and a life-size correcting unit for correcting the radiation image information from the panel based on the information of the calculated radiation field and the information of the calculated hypothetical radiation field.

Abstract: An apparatus and method for testing integrity of a wired communication link includes receiving a plurality of signals, sent by at least one transmitter over the wired communications link, at corresponding multiple receivers. The signals have corresponding frequencies within a frequency range of the wired communication link, such that the frequencies are representative of the frequency range. A signal loss corresponding to each of the frequencies is measured, and an indication of whether each measured signal loss is within an acceptable range is provided. The wired communication link may be a coaxial cable.

Abstract: The present disclosure provides a system and method for detecting faults related to lines linked to provide network services. The method includes storing a synthetic value for the performance of a line, receiving a measured value of a performance parameter of the line measured at a customer end and comparing the synthetic value with the measured value to determine if a fault condition exists.

Abstract: A messaging system is provided that includes: (a) an interface 206 for receiving a request to play a message audibly to a subscriber; and (b) a message retrieval agent 224 for determining whether the message comprises marked information. When the message comprises marked information, the agent 224 performs one or more of the following operations: (b1) display the marked information to the subscriber; (b2) alter an audio playback speed of the marked information to the subscriber, the playback speed of the marked information being different from a playback speed of unmarked information; and (b3) audibly play only one of the marked information and unmarked information to the subscriber.

Abstract: A method and apparatus are provided for processing a contact with a client of an organization. The method includes the steps of a contact processing resource of the organization detecting a contact with the client through a first communication channel operating under a first communication format, the contact processing resource generating an information request based upon the contact with the client, transferring the information request to a media server of the organization and the media server sending an information response to the client through a second communication channel operating under a second communication format.