Abstract: A laser apparatus is provided which is capable of achieving deep penetration into an aluminum-like metal material without causing welding defects such as spatters or cracks and performing high-speed pulse seam welding. The laser apparatus includes a pulse power source that generates a current signal and a mask signal for masking a fluctuation component included in the current signal, and which supplies a current signal in which a fluctuation component has been masked by the mask signal to a YAG pulsed laser oscillator. In addition, the laser apparatus sets the spot shape of a CW laser light oscillated by a CW laser oscillator to a rhombic streamlined shape, and causes a focus spot of the CW laser light to include a circular focus spot of a pulsed laser light.

Abstract: Methods and apparatus for maintaining a quality of a Raman medium in a Raman conversion cell. In various examples, a flow velocity of the Raman medium is tailored based on a spatial nonuniformity of heat deposition resulting from the Raman conversion in the cell. In particular, in one example, the flow velocity of the Raman medium may be tailored to be higher where the heat deposition/temperature rise is larger and smaller elsewhere in the cell. This type of flow velocity profile reduces the overall required volumetric flow of the Raman medium in the cell without significantly affecting a quality of the Raman medium.

Abstract: A laser. The novel laser includes a gain medium, a pump source adapted to optically excite the gain medium in a first location, and a resonator adapted to extract energy from the gain medium in a second location distinct from the first location. In an illustrative embodiment, the gain medium is comprised of a plurality of solid-state gain particles suspended in a fluid. The gain medium is adapted to flow, and optical excitation of the gain medium occurs outside of the resonator. In a preferred embodiment, the flow velocity and the density of gain particles in the gain medium are adjusted for optimal absorption efficiency during optical excitation and then for optimal extraction efficiency in the resonator. In addition, the resonator may be shaped for optimal extraction efficiency, while pump modules that hold the gain medium during optical excitation are shaped for optimal absorption efficiency.

Abstract: Current channels, blocking areas, or strips in a semiconductor laser are used to channel injected current into the antinodal region of the optical standing wave present in the optical cavity, while restricting the current flow to the nodal regions. Previous devices injected current into both the nodal and antinodal regions of the wave, which is fed by the population inversion created in the active region by the injected electrons and holes, but inversion created in the nodal regions is lost to fluorescence or supports the creation of undesirable competing longitudinal modes, causing inefficiency. Directing current to the antinodal regions where the electric field is at its maximum causes a selected longitudinal mode to preferentially oscillate regardless of where the longitudinal mode lies with respect to the gain curve. In one embodiment, exacting fabrication of the Fabry-Perot cavity correlates the current channels to antinodal regions, vis-a vis current blocking areas, strips or segmented layers.

Abstract: A nitride semiconductor laser element comprises; a nitride semiconductor layer that includes a first nitride semiconductor layer, an active layer, and a second nitride semiconductor layer, and that has a cavity with end faces, and a protective film formed on at least one end face of the cavity, wherein the protective film is formed of a first film with a crystal structure that has the same axial orientation as that of the nitride semiconductor layer constituting the end face of the cavity, and a second film with a crystal structure that has a different axial orientation from that of the first film, in this order from the side of the end face.

Abstract: An edge emitting semiconductor laser containing a plurality of monolithically integrated laser diodes (1, 2, 3). Each laser diode (1, 2, 3) contains an active zone (11, 12, 13), with the active zones (11, 12, 13) being in each case arranged between waveguide layers (6), the waveguide layers (6) in each case adjoining a cladding layer (7, 8) at a side remote from the active zone (11, 12, 13). The cladding layers (7, 8) comprise inner cladding layers (7), which are arranged above a bottommost active zone (11) and below a topmost active zone (13), and outer cladding layers (8) which are arranged below the bottommost active zone (11) or above the topmost active zone (13). The inner cladding layers (7) have a smaller thickness than the outer cladding layers (8).

Abstract: A method and apparatus for allocating subcarriers in a broadband wireless communication system using multiple carriers are provided. In the wireless communication system where the total available frequency band is divided into a plurality of subcarriers and subchannels each are formed with a predetermined number of subcarriers, the subcarriers are grouped into subcarrier groups, subcarriers are selected from the subcarrier groups according to predetermined sequences, and the selected subcarriers are allocated as a subchannel to a cell in a predetermined time period.

Abstract: According to one embodiment, a lower order modulator is provided using a number of higher order modulators. According to another embodiment, a signal having a lower order spreading factor is generated using circuitry for generating a number of signals with a higher order spreading factor.

Abstract: Wireless communication receiver with hybrid equalizer and RAKE receiver. The receiver compares performance of the system for RAKE only and RAKE in combination with equalizer estimates. The receiver enables or disables the equalizer accordingly.

Abstract: An apparatus and method for estimating and combining frequency errors in a mobile communication system. A controller divides data received from a main base station (BS) and control information received from a neighbor BS and controls allocation to fingers. A main automatic frequency control (AFC) loop is formed by estimating and combining frequency errors of the data received from the main BS. A sub AFC loop is formed by subtracting a corrected value of the main AFC loop after estimating and combining frequency errors of the control information received from the neighbor BS.

Abstract: A system and method for improving bit-loading in discrete multitone (DMT)-based digital subscriber line (DSL) modems. In one embodiment, the system includes: (1) a model generator configured to generate a model containing a calculated total bit loading for an assumed gross coding gain and estimated total bit loadings for a other plurality of assumed gross coding gains and (2) a bit loader associated with the model generator and configured to load bits in accordance with the model.

Abstract: A terminal for receiving digital broadcast signals includes signal receiving components for receiving a digital broadcast signal, and a first error rate detection unit for detecting a first bit error rate (BER) of the digital broadcast signal before the digital broadcast signal is decoded by a decoder. The terminal also includes a second error rate detection unit for detecting a second bit error rate (BER) of the digital broadcast signal after the digital broadcast signal is decoded by the decoder, and a packet error rate detection unit for detecting packet error rate (PER) of the digital broadcast signal. The terminal typically further includes a controller for determining reception quality of the digital broadcast signal based upon a value of the first BER, or the second BER, or the PER. A method for determining signal reception quality includes receiving a digital broadcast signal, detecting the BER, and determining reception quality of the digital broadcast signal based upon a value of the BER.

Abstract: An apparatus for improved reception of a signal is described. The apparatus includes an equalizer that has at least two cascaded maximum-likelihood detectors and an adjustable delay unit. The equalizer and the adjustable delay unit are configured for adaptation in accordance with one or more multi-path signals in a communication channel that conveys the signal.

Abstract: An analog equalizer (613 and 614) adaptively equalizes an input analog signal affected with intersymbol interference (“ISI”), or an intermediate analog signal generated therefrom, to produce a filtered partially equalized analog signal with reduced ISI. An analog-to-digital converter (210) converts the filtered analog signal, or an intermediate analog signal generated therefrom, into an initial digital signal. A digital equalizer (212) adaptively equalizes the initial digital signal, or an intermediate digital signal generated therefrom, to produce an equalized digital signal as a stream of equalized digital values with further reduced ISI. An output decoder (605) decodes the equalized digital values, or intermediate digital values generated therefrom, into a stream of symbols.

Abstract: A pulse width modulation (PWM) generator having asynchronous updating of its PWM duty cycle and/or period values allows immediate correction for the new PWM duty cycle and/or period values instead of waiting until the end of a PWM period to accept the new duty cycle and/or period values. This reduces the latency in a control loop when responding to changing system status, e.g., changes in PWM duty cycle. Also the PWM duty cycle is prevented from “running away” (e.g., missing a PWM cycle) if the PWM duty cycle timer/counter has advanced beyond an updated duty-cycle maximum value.

Abstract: A system and method are disclosed for decoding signals of a block of image data. The method comprises receiving a parameter or an index associated with a direction of a plurality of prediction directions and decoding a block of image data utilizing image data predicted from an adjacent block according to direction associated with the parameter. The prediction direction may be at least one of horizontal, vertical or diagonal. A system and method are also disclosed for encoding blocks of image data including a parameter or an index associated with a direction of a plurality of prediction directions.

Abstract: Improved video coding is described to encode video data within a sequence of video frames. To this end, at least a portion of a reference frame is encoded to include motion information associated with the portion of the reference frame. At least a portion of a predictable frame that includes video data predictively correlated to said portion of said reference frame is defined based on the motion information. At least said portion of the predictable frame is encoded without including corresponding motion information and including mode identifying data. The mode identifying data indicate that the encoded portion of the predictable frame can be directly derived using at least the motion information associated with the portion of the reference frame.

Abstract: A method of determining a reference picture, a method of compensating for a motion, and an apparatus therefore are provided. The method of determining a reference picture blocks constituting a current picture includes: (a) preparing tag information describing a plurality of pictures; and (b) determining one of the plurality of pictures to be a reference picture by referring to the tag information.

Abstract: Encoding functionality is described for producing encoded intra (I) pictures and predictive (P) pictures for consumption by an application running on a set-top box. The encoding functionality includes a pre-processing module which marks regions that should not be updated with a predetermined color code. An encoding module receives the output of the pre-processing module, and, in the event that the output contains the predetermined color code, produces a predictive (P) picture. In the predictive (P) picture, the encoding module produces macroblocks having zero motion vector and zero difference (or skipped macroblocks) corresponding to regions that were marked by the pre-processing module with the predetermined color code. The encoding module produces intra macroblocks for other regions of the picture (corresponding to update regions).

Abstract: An encoding circuit transforms a picture signal into blocks of, for example, 8*8 coefficients, in which each block of coefficients is read motion- adaptively. In the case of motion within a sub-picture, the block of coefficients is read in such an order that the obtained series of coefficients includes, as it were, two interleaved sub-series. The first series starts with a dc component. In a first embodiment, the second series starts with the most relevant motion coefficient. In a second embodiment, two interlaced sub-fields are separately transformed and the second series also starts with a dc coefficient. As a result, the coefficients are transmitted as much as possible in their order of significance. This particularly produces the largest possible clusters of zero value coefficients. Such clusters are transmitted as one compact run-length code so that an effective bit rate reduction is achieved, also for moving pictures.

Abstract: A method for transcoding between videostreams using different entropy coding, comprising the steps of (A) decoding a first videostream using a first set of entropy codes, and (B) generating a second videostream by entropy encoding the decoded first videostream using a second set of entropy codes. The first set of entropy codes and the second set of entropy codes are configured to represent all valid coefficient values of the first videostream.

Abstract: An apparatus comprising a first processing circuit and a second processing circuit. The first processing circuit may be configured to generate a plurality of reconstructed samples in response to one or more macroblocks of an input signal. The second processing circuit may be configured to determine a best intra prediction chroma mode 0 predictor for reach chroma sub-block of a current macroblock in response to available reconstructed samples adjacent to the current macroblock.

Abstract: A method and system including an improved generalized reference decoder that operates according to any number of sets of rate and buffer parameters for a given bit stream. Each set characterizes a leaky bucket model and contains three parameters representing the transmission bit rate, buffer size, and initial decoder buffer fullness. An encoder provides at least two sets of these parameters, whereby the decoder selects one or interpolates between them to operate at any desired peak bit rate, buffer size or delay. The generalized reference decoder may select the smallest buffer size and corresponding delay that decodes the bit stream without buffer underflow or overflow, or alternatively may select and operate at the minimum required peak transmission rate, or something between both. In practice, the buffer size, delay and/or the peak transmission rate can be reduced by significant factors, and/or the signal-to-noise ratio (SNR) can be increased.

Abstract: An accelerated video decoding system utilizes a graphics processing unit to perform motion compensation, image reconstruction, and color space conversion processes, while utilizing a central processing unit to perform other decoding processes.

Abstract: In the video signals provided by broadcasting media, advertising sections are inserted between normal programs, thus causing interruption. An end portion of the normal program will be repeated before an advertising section ends. The invention determines the continuity of two adjacent frames, to search for frame discontinuity to find out if there is a frame similar to a next given frame. If a similar frame is found to have an advertising frame, an advertisement is detected.

Abstract: A transmission apparatus used in a radio communication system adopting the OFDM scheme is disclosed. The transmission apparatus includes: a dividing inverse Fourier transform part including plural transform parts, wherein the dividing inverse Fourier transform part divides a signal to be transmitted into plural signals, and each of the plural transform parts performs inverse Fourier transform on one of the plural signals; a peak control part for outputting a peak control signal based on peaks that are detected from output signals of the dividing inverse Fourier transform part; and a peak reducing process part for adjusting a weight or an arranging order of an output signal of the dividing inverse Fourier transform part according to the peak control signal to output an adjusted signal, and synthesizing the adjusted signal with other signal so as to output a synthesized signal.

Abstract: A baseband processor includes a demodulator that demodulates a symbol received by a maximum ratio combining (MRC) receiver via receive pathways. A viterbi decoder generates branch metrics for decoding the symbol. The branch metrics are generated based on a channel state information (CSI) of the symbol.

Abstract: A transmitting apparatus that transmits signals from a plurality of antennas, and can improve the security of communication compared with a conventional system. In this apparatus, an antenna changing section (105) stores an antenna change pattern in internal memory, and each time a clock signal is input, generates an antenna change signal directing an antenna change in accordance with the antenna change pattern, and outputs this signal to an antenna selection section (106). Based on the antenna change signal, the antenna selection section (106) selects two different antennas from among the transmitting antennas (107-1 through 107-3) as transmitting antennas of transmit signal A output from a radio section (104-1) and transmit signal B output from a radio section (104-2), and performs radio transmission of transmit signal A and transmit signal B using the selected transmitting antennas.

Abstract: A technique to determine sampling frequency offset (SFO) phase shift and perform channel estimation for symbols of a signal communicated across a multiple-input-multiple-output (MIMO) communication channel, in which preambles utilized for channel estimation are sent over more than one time block. Because the transmission of preambles used for channel estimation are sent over multiple time blocks, a SFO phase shift that is linear across tones of an OFDM signal is experienced between preambles of the two time blocks. Upon detection of the SFO phase shift, a weighting matrix used for channel estimation is modified to account for the SFO phase shift, in order to perform the channel estimation with correction for the SFO phase shift.

Abstract: Aspects of a method and system for a fast-switching Phase-Locked Loop using a Direct Digital Frequency synthesizer may include generating a second signal from a first signal by: frequency translating an inphase component of the first signal utilizing a filtered fast-switching oscillating signal generated using at least a direct digital frequency synthesizer (DDFS), and frequency translating a corresponding quadrature component of the first signal utilizing a phase-shifted version of the generated and filtered fast-switching oscillating signal. The inphase and quadrature components of the first signal may be multiplied with the filtered fast-switching oscillating signal and a phase-shifted version of the filtered fast-switching oscillating signal, respectively.

Abstract: To realize variable control of the output value of impulses with a simple construction, the present device includes an impulse generating unit which generates impulses; and a control unit which controls an output value of impulses output from the impulse generating unit by changing an input signal that is input to the impulse generating unit for generating impulses.

Abstract: A type dependency modulation method with type control is integrated with type control code words in traditional type dependency modulation. It increases the effect of DC component control in the overall encoding procedure. In this method, a specific type-control code word is inserted at certain intervals in the encoding procedure, increasing the selectable code words in subsequent encoding procedures, thereby improving the DC component control ability.

Abstract: A detector (1) for zero crossings and a counter (2) which is connected to it are used to determine the time intervals between the zero crossings of the received signal or of an intermediate-frequency signal which is produced from the received signal, and for detection of the digital signal data. In this case, a sequence of determined zero crossing intervals can be stored in digital form in a shift register chain (3), and can be compared in a classification device (4) with previously stored interval sequences. Furthermore, a frequency offset can be determined by averaging the zero crossing intervals and can be compensated for by suitable selection or modification of the previously stored interval sequences, in which case the latter can also be used during the synchronization phase. The synchronization process may, furthermore, be assisted by payload data identification.

Abstract: A digital broadcasting system and a data processing method are disclosed. The receiving system of the digital broadcasting system includes a baseband processor, a first handler, a second handler, and a storage unit. The baseband processor receives a broadcast signal including mobile service data and main service data. Herein, the mobile service data may configure an RS frame, and the RS frame may include the mobile service data and first signaling information of a first data type on the mobile service data. The first handler parses the first signaling information received from the RS frame, converts parsed data elements of the first data type to a second data type, and merges multiple identification information of the parsed first data type, thereby generating identification information of the second data type.

Abstract: A composite data detector having first and second data detectors. The second detector of the invention starts in a known state and only runs as long as is necessary before being switched off and handing control back over to the smaller detector. Therefore, the composite data detector of the invention consumes less power than the known composite data detector and estimates bits with higher accuracy.

Abstract: In ranging systems such as GPS, radar, and the like, accuracy of the ranging information recovered depends on the phase linearity of the ranging receiver, generally implemented as a superheterodyne radio. Superheterodyne radios use bandpass filters in their Intermediate Frequency (IF) amplifiers to accomplish suppression of adjacent channel signal interference. Depending on the ratio of IF center-frequency to signal-bandwidth, such filters evidence phase non-linearity affecting the signal group delay response. This generally manifests in coupling of the in-phase and quadrature detected signals during signal modulation changes in state. If this effect is ignored, reduced accuracy in the recovery of ranging information can be expected. One solution is to incorporate in the ranging receiver a phase non-linearity compensation structure, but this has an adverse economic impact.

Abstract: The present invention relates to a method and a device for data extraction from a data stream containing at least one data packet. First, comparing a bit stream derived from a received digital data stream with an expected bit sequence is performed by packet detector to determine a correlation value (CorrVal) for detecting a data packet. Then, a data extraction unit is started for data extraction when the correlation value (CorrVal) exceeds a threshold value (CorrThres) indicating that a data packet has been detected. Therefore, comparing the received bit stream with the expected bit sequence to determine a new correlation value (CorrVal) is continued by the packet detector. Finally, restarting data extraction is initiated by a sync-control module when the new correlation value (CorrVal) exceeds the form correlation value (MaxCorrVal).

Abstract: A signal receiver includes a sampling device for sampling a received signal carrying a stream of symbols to form a first set of actual samples. The signal receiver also includes interpolation means for interpolating between the samples of the first set to form a second set of interpolated samples. The signal receiver also includes symbol recovery means configured to process the first and second sets of samples so as to form an estimate of the symbols of the signal. The processing includes performing a temporal whitening step on signals derived from first and second sets of samples. The signal receiver also includes signal combining means using a matched filter and averaging technique.

Abstract: Systems and techniques relating to channel equalization in received communications signals are described. In one aspect, a communications signal of a channel is obtained and channel effects are removed from the communications signal by generating one or more time-varying channel response estimates.

Abstract: A satellite communications system provides an information channel between remotely located transmitters and receivers. A virtual satellite system provides the same service, but divides the signal either in power or in data content into subchannels such that any particular signal is conducted to the intended receiver via a plurality of traditional satellite channels. The receiving terminal accepts the plurality of signals simultaneously from a possible plurality of satellites, combining the subchannels comprising the virtual channel into the original signal content as if conducted via a single channel. The receiving antenna system receives satellite subchannel signals from a plurality of directions using multiple antennas or a single antenna with multi-direction capability. Prior to signal combining, the receiver necessarily time-synchronizes the plurality of subchannels by introducing time delay in some channels before combining the subsignals into the original composite.

Abstract: A method for automatically calibrating intra-cycle timing relationships between command signals, data signals, and sampling signals for an integrated circuit device. The method includes generating command signals for accessing an integrated circuit component, accessing data signals for conveying data for the integrated circuit component, and accessing sampling signals for controlling the sampling of the data signals. A phase relationship between the command signals, the data signals, and the sampling signals is automatically adjusted to calibrate operation of the integrated circuit device.

Abstract: Techniques are provided for calculating a clock rate for a serial clock of a transmitter where information sent by the transmitter is sent in packets from the transmitter over an asynchronous network. The techniques involve minimizing the number of adjustments to the clock rate that are needed to fine tune the clock rate to match the serial clock of the transmitter.

Abstract: A method and apparatus are provided for implementing bandwidth control in a communication link. A set link configuration for the communications link establishes a number of clock cycles required to transmit a data envelope. A control function aligns a start of a data packet on a fixed cycle boundary for data envelope transmissions. The control function aligns the start of a data packet in the same byte of the 16 byte field. The control function is implemented with a memory management input/output (MMIO) register and a counter, and allows a transmitting side of the communications link to control the pacing of data packet transmission or bandwidth by aligning all data packets on fixed-cycle boundaries.

Abstract: The illustrative embodiments provide accurate time-based counters for scaling operating frequencies of microprocessors. A time-based counter circuit configuration in which a fixed frequency clock is derived from a PLL of the clock generation circuit of the microprocessor and is used to feed the external and internal timebase logic as well as a timebase accumulator counter. The timebase accumulator counter accumulates the tick events from the timebase logic between two core clocks. The accumulated value is transferred to the core clock domain on every clock edge of a scalable clock and the accumulator is then reset. Because the accumulated ticks are transferred to the core clock domain before the accumulator is reset, no ticks are ever lost using the circuitry of the illustrative embodiment.

Abstract: A unified, unidirectional serial link is described for providing data across wired media, such as a chip-to chip or a card-to-card interconnect. It consists of a transmit section and a receive section that are operated as pairs to allow the serial data communication. The serial link is implemented as part of a VLSI ASIC module and derives its power, data and clocking requirements from the host modules. The logic transmitter portion contains a phase locked loop (PLL), a dibit data register, a finite impulse response (FIR) filter and a transmit data register. The phase locked loop comprises both a digital coarse loop and an analog fine loop. The digital receiver portion contains a PLL, an FIR phase rotator, a phase rotator control state machine, and a clock buffer. The transmitter and the receiver each preferably utilize a pseudo-random bit stream (PRBS) generator and checker.

Abstract: A method of inputting data to an integrated circuit is disclosed. A plurality of data signals are serially received from a source external to the integrated circuit. A strobe signal is derived from the plurality of data signals. The deriving is done by circuitry within the integrated circuit. The data signals can be latched at an input of the integrated circuit using the strobe signal that was derived within the integrated circuit.

Abstract: A shift register has multiple stages each of which includes a pull-up part to generate a current gate line driving signal having a first state in response to a first control signal and a clock signal, a pull-down part to generate the current gate line driving signal having a second state in response to a second control signal, a pull-up driver to generate the first control signal to control the pull-up part in response to a previous gate line driving signal provided from a previous stage, a following gate line driving signal provided from a following stage, and an input voltage signal externally provided, and a pull-down driver to generate the second control signal to control the pull-down part in response to a third control signal provided from the pull-up driver and the input voltage signal, in which the second control signal swings between first and second voltage levels in association with the input voltage signal that swings between predetermined voltage levels.

Abstract: A method for obtaining data includes scanning an object using a CT imaging system having at least two detector rows to acquire projection data, wherein the projection data includes at least some data obtained from at least two rows of the detector array, and reconstructing data representative an image of the object utilizing the projection data wherein the reconstruction includes pipelining the acquired projection data through a pipeline of operations including column-filtering, tomographic filtering, and backprojection. Thick reconstructed images using 3D backprojection can be obtained with significantly lessened artifacts relative to conventional 3D backprojection image reconstructions.

Abstract: A method is disclosed for producing projective and tomographic phase contrast images of an examination object, preferably a patient, with the aid of an X-ray system, and a corresponding X-ray system for carrying out this method. In at least one embodiment of the method, X-ray optical grating sets tuned to different energy ranges are used to determine energy-dependent phase shifts upon penetration of an examination object, a difference value is formed from these energy-dependent phase shifts, and tomographic or projective images are produced therefrom.

Abstract: Method for operating a medical examination apparatus, having an image recording device, which is moved in a rotary motion through a predetermined angular range around the patient in order to produce image recordings of a periodically moving object, with several runs being carried out by the image recording device in order to produce the image recordings and the start of the individual runs being initiated as a function of a reference signal, which represents a current movement status of the organ to be mapped, such that image recordings are produced at different radiation angles with each run.