3824 results about "Pulse sequence" patented technology

A multi-ladar sensor system is proposed for operating in dense environments where many ladar sensors are transmitting and receiving burst mode light in the same space, as may be typical of an automotive application. The system makes use of several techniques to reduce mutual interference between independently operating ladar sensors. In one embodiment, the individual ladar sensors are each assigned a wavelength of operation, and an optical receive filter for blocking the light transmitted at other wavelengths, an example of wavelength division multiplexing (WDM). Each ladar sensor, or platform, may also be assigned a pulse width selected from a list, and may use a pulse width discriminator circuit to separate pulses of interest from the clutter of other transmitters. Higher level coding, involving pulse sequences and code sequence correlation, may be implemented in a system of code division multiplexing, CDM. A digital processor optimized to execute mathematical operations is described which has a hardware implemented floating point divider, allowing for real time processing of received ladar pulses, and sequences of pulses.

Techniques for reducing peak-to-average power in multicarrier transmitters employ peak cancellation with subcarriers that are impaired by existing channel conditions. The use of Carrier Interferometry (CI) coding further improves the effectiveness of peak reduction. CI coding can also be impressed onto pulse sequences in the time domain, which enhances spectral selection and facilitates peak-power control.

Methods for processing an amorphous silicon thin film sample into a polycrystalline silicon thin film are disclosed. In one preferred arrangement, a method includes the steps of generating a sequence of excimer laser pulses, controllably modulating each excimer laser pulse in the sequence to a predetermined fluence, homoginizing each modulated laser pulse in the sequence in a predetermined plane, masking portions of each homogenized fluence controlled laser pulse in the sequence with a two dimensional pattern of slits to generate a sequence of fluence controlled pulses of line patterned beamlets, each slit in the pattern of slits being sufficiently narrow to prevent inducement of significant nucleation in region of a silicon thin film sample irradiated by a beam let corresponding to the slit, irradiating an amorphous silicon thin film sample with the sequence of fluence controlled slit patterned beamlets to effect melting of portions thereof corresponding to each fluence controlled patterned beamlet pulse in the sequence of pulses of patterned beamlets, and controllably sequentially translating a relative position of the sample with respect to each of the fluence controlled pulse of slit patterned beamlets to thereby process the amorphous silicon thin film sample into a single or polycrystalline silicon thin film.

A hand held device generates a predetermined number of pulses of electromagnetic radiation having a predetermined electromagnetic spectrum, a predetermined duration, a predetermined inter-pulse interval, and a predetermined total energy. The pulse sequence is delivered to a skin surface to reduce or eliminate Xray or ultraviolet radiation damage to the skin surface.

Methods and systems for performing three dimensional LIDAR measurements with different pulse repetition patterns are described herein. Each repetitive pattern is a sequence of measurement pulses that repeat over time. In one aspect, the repetition pattern of a pulsed beam of illumination light emitted from a LIDAR system is varied to reduce total energy consumption and heat generated by the LIDAR system. In some examples, the repetitive pattern is varied by skipping a number of pulses. In some examples, the repetitive pattern of pulses of illumination light emitted from the LIDAR system is varied by changing a repetition rate of the sequence of emitted pulses. In some examples, the pulse repetition pattern is varied based on the orientation of the LIDAR device. In some examples, the repetition pattern is varied based on an object detected by the LIDAR device or another imaging system.

Methods and systems for performing multiple pulse LIDAR measurements are presented herein. In one aspect, each LIDAR measurement beam illuminates a location in a three dimensional environment with a sequence of multiple pulses of illumination light. Light reflected from the location is detected by a photosensitive detector of the LIDAR system during a measurement window having a duration that is greater than or equal to the time of flight of light from the LIDAR system out to the programmed range of the LIDAR system, and back. The pulses in a measurement pulse sequence can vary in magnitude and duration. Furthermore, the delay between pulses and the number of pulses in each measurement pulse sequence can also be varied. In some embodiments, the multi-pulse illumination beam is encoded and the return measurement pulse sequence is decoded to distinguish the measurement pulse sequence from exogenous signals.

A system and a method for distance measurement utilizes a radio system. The distance is measured by determining the time it takes a pulse train to travel from a first radio transceiver to a second radio transceiver and then from the second radio transceiver back to the first radio transceiver. The actual measurement is a two step process. In the first step, the distance is measured in coarse resolution, and in the second step, the distance is measured in fine resolution. A first pulse train is transmitted using a transmit time base from the first radio transceiver. The first pulse train is received at a second radio transceiver. The second radio transceiver synchronizes its time base with the first pulse train before transmitting a second pulse train back to the first radio transceiver, which then synchronizes a receive time base with the second pulse train. The time delay between the transmit time base and the receive time base can then be determined. The time delay indicates the total time of flight of the first and second pulse trains. The time delay comprises coarse and fine distance attributes. The coarse distance between the first and second radio transceivers is determined. The coarse distance represents the distance between the first and second radio transceivers in coarse resolution. An in phase (I) signal and a quadrature (Q) signal are produced from the time delay to determine the fine distance attribute. The fine distance indicates the distance between the first and second transceivers in fine resolution. The distance between the first and second radio transceivers is then determined from the coarse distance and the fine distance attributes.

A laser-based system for processing target material within a microscopic region without causing undesirable changes in electrical or physical characteristics of at least one material surrounding the target material, the system includes a seed laser, an optical amplifier, and a beam delivery system. The seed laser for generating a sequence of laser pulses having a first pre-determined wavelength. The optical amplifier for amplifying at least a portion of the sequence of pulses to obtain an amplified sequence of output pulses. The beam delivery system for delivering and focusing at least one pulse of the amplified sequence of pulses onto the target material. The at least one output pulse having a pulse duration in the range of about 10 picoseconds to less than 1 nanosecond. The pulse duration being within a thermal processing range. The at least one focused output pulse having sufficient power density at a location within the target material to reduce the reflectivity of the target material and efficiently couple the focused output into the target material to remove the target material.

A multi-ladar sensor system is proposed for operating in dense environments where many ladar sensors are transmitting and receiving burst mode light in the same space, as may be typical of an automotive application. The system makes use of several techniques to reduce mutual interference between independently operating ladar sensors. In one embodiment, the individual ladar sensors are each assigned a wavelength of operation, and an optical receive filter for blocking the light transmitted at other wavelengths, an example of wavelength division multiplexing (WDM). Each ladar sensor, or platform, may also be assigned a pulse width selected from a list, and may use a pulse width discriminator circuit to separate pulses of interest from the clutter of other transmitters. Higher level coding, involving pulse sequences and code sequence correlation, may be implemented in a system of code division multiplexing, CDM. A digital processor optimized to execute mathematical operations is described which has a hardware implemented floating point divider, allowing for real time processing of received ladar pulses, and sequences of pulses.

Methods and systems for performing three dimensional LIDAR measurements with different illumination intensity patterns are described herein. Repetitive sequences of measurement pulses each having different illumination intensity patterns are emitted from a LIDAR system. One or more pulses of each repetitive sequence have a different illumination intensity than another pulse within the sequence. The illumination intensity patterns are varied to reduce total energy consumption and heat generated by the LIDAR system. In some examples, the illumination intensity pattern is varied based on the orientation of the LIDAR device. In some examples, the illumination intensity pattern is varied based on the distance between a detected object and the LIDAR device. In some examples, the illumination intensity pattern is varied based on the presence of an object detected by the LIDAR device or another imaging system.

A system and method are provided that can detect any part of a multipath impulse radio signal. More specifically, the method compares a template pulse train and the multipath impulse radio signal to obtain a comparison result. The system performs a threshold check on the comparison result. If the comparison result passes the threshold check, the system locks onto any part of the multipath impulse radio signal including a direct path part and at least one multipath reflection part. The system may also perform a quick check, a sychronization check, and / or a command check of the multipath impulse radio signal.

A system, method and computer program product for positioning pulses, including positioning pulses within a specified time layout according to one or more codes to produce a pulse train having one or more predefined spectral characteristics where a difference in time position between adjacent pulses positioned to produce a spectral characteristic differs from another difference in time position between other adjacent pulses positioned to produce the spectral characteristic. The present invention may include shaping a code spectrum according to a spectral template in order to preserve a pre-defined code characteristic. A pre-defined code characteristic can include desirable correlation, or spectral properties. A transmitter incorporating the present invention can avoid transmitting at a particular frequency. Similarly, a receiver can avoid interference with a signal transmitting at a particular frequency. A radar system, can avoid a radar jammer attempting to jam a particular frequency.

An electrical stimulation device and method for the treatment of dysphagia is disclosed. In a preferred embodiment, the electrical stimulation device includes one or more channels of electrodes each of which includes a first electrode positioned in electrical contact with tissue of a target region of a patient and a second electrode positioned in electrical contact with tissue of a posterior neck region or a posterior thoracic region of the patient. A series of electrical pulses are then applied to the patient through the one or more channels of electrodes in accordance with a procedure for treating dysphagia. The series of electrical pulses may comprise: a plurality of cycles of a biphasic sequential pulse train pattern; a plurality of cycles of a biphasic overlapping pulse train pattern; a plurality of cycles of a triphasic sequential pulse train pattern; a plurality of cycles of a triphasic overlapping pulse train pattern; a functional pulse train pattern; a low-frequency pulse train pattern; or a frequency-sequenced pulse burst train pattern. Various exemplary embodiments of the invention are disclosed.

An autonomous active medical implantable device, with a power supply and a wake-up circuit that responds to receipt of specific pulses transmitted through the interstitial tissues of the body transmitter device (40) generates trains of modulated pulses applied to electrodes (22, 24), and a receiver (50) processes (e.g., filter, amplify and demodulate) pulses collected on electrodes (22′, 24′). The receiver circuits (50) are selectively activated from a dormant (sleep) state in which they are not powered by a power source (34), to an operational (active) state in which they are powered and able to process (e.g., filter, amplify and demodulate) the collected pulses specific wake-up pulse train, configured in a predetermined characteristic pulse pattern triggers passive wake-up circuits (66) in the receiver (50) to switch the receiver circuits from the sleep state to the operational state.

A percutaneous, intramuscular stimulation system for therapeutic electrical stimulation of select muscles of a patient includes a plurality of intramuscular stimulation electrodes (50) for implantation directly into select muscles of a patient and an external battery-operated, microprocessor-based stimulation pulse train generator (10) for generating select electrical stimulation pulse train signals (T). A plurality of insulated electrode leads (40) percutaneously, electrically interconnect the plurality of intramuscular stimulation electrodes (50) to the external stimulation pulse train generator (10), respectively. The external pulse train generator (10) includes a plurality of electrical stimulation pulse train output channels (E) connected respectively to the plurality of percutaneous electrode leads (40) and input means (24,26,28) for operator selection of stimulation pulse train parameters (PA,PD,PF) for each of the stimulation pulse train output channels (E) independently of the other channels. Visual output means (20) provides visual output data to an operator of the pulse train generator (10). Non-volatile memory means (66,68) stores the stimulation pulse train parameters for each of the plurality of stimulation pulse train output channels (E). The generator (10) includes means for generating stimulation pulse train signals (100,102) with the selected pulse train parameters on each of the plurality of stimulation pulse train output channels (E) so that stimulus pulses of the pulse train signals having the select stimulation pulse train parameters pass between the intramuscular electrodes (50) respectively connected to the stimulation pulse train output channels (E) and a reference electrode (52).

A device for detecting the position of a human finger or other object on a touch-sensitive scrolling pad. Dual independent oscillators may be used to generate two pulse trains at frequencies dependent upon the capacitance of two conductors resulting from the position of the finger on the conductors. The pulses from each oscillator may be counted over a time interval. A ratio-metric measurement may be taken by calculating the ratio of the two counts, and a sum may also be calculated. The ratio of the two counts relates to finger position on the device, and their sum relates to finger pressure upon the device.

A method for improving the intelligibility of an incoming telephone signal, including boosting loudness of at least one band of poorly heard frequencies of the signal within at least one band of intensities of the signal, the band lying below a predetermined intensity level at which telephone standard conformance testing is performed, thereby to generate a differentially boosted telephone signal. Alternatively or in addition, intelligibility of sibilants in a narrow band telephone signal is enhanced, by doubling the sampling rate of the narrow band signal by interpolation, thereby to provide a narrow band interpolated signal, generating a harmonic extrapolation signal by harmonically extrapolating from the narrow band interpolated signal thereby to estimate the missing portions of the telephone signal, the harmonic extrapolation comprising a sequence of pulses located at peaks of the interpolated signal, generating a missing energy estimator measure estimating energy missing at high frequency bands of the telephone signal, continuously modulating the amplitude of the pulses in said sequence of pulses based on said missing energy estimator measure, thereby to generate a modulated signal, passing the modulated signal through a shaping filter thereby to obtain a shaped signal, and summing the shaped signal with the interpolated signal.

A desired pattern may be cut into a stent preform by impinging a laser beam onto the stent preform. The laser beam is formed using a laser system comprising a resonator cavity for resonating laser radiation, a gain medium contained in the resonator cavity, a pump for periodically pumping the gain medium and an electro-optical modulator in communication with the resonator cavity. The laser system produces a radiation pulse for each pump period. Each radiation pulse is conditioned by suppressing at least a portion of the pulse. The pulse may also be modulated with an electro-optical modulator to produce a pulse train of ordered pulses of radiation. Each pulse train is output from the optical cavity as an output laser beam which is directed at the stent preform to cut a desired pattern in the stent preform.

A reader for a radio frequency identification system capable of simultaneously reading tags operating a multiple frequencies. The reader includes a radio frequency module for each operating frequency of the tags. The radio frequency modules are coupled to a bus which is connected to an interrogator control module. Each of the radio frequency modules receives the return signal from the tags at the associated operating frequency and converts the return signal into a pulse sequence. The interrogator control module locks to and decodes the pulse sequence according to the protocol associated with the tag type.

The present invention relates to a method of measuring motion of an object such as a heart by magnetic resonance imaging. A pulse sequence is applied to spatially modulate a region of interest of the object and at least one first spectral peak is acquired from the Fourier domain of the spatially modulated object. The inverse Fourier transform information of the acquired first spectral-peaks is computed and a computed first harmonic phase image is determined from each spectral peak. The process is repeated to create a second harmonic phase image from each second spectral peak and the strain is determined from the first and second harmonic phase images. In a preferred embodiment, the method is employed to determine strain within the myocardium and to determine change in position of a point at two different times which may result in an increased distance or reduced distance. The method may be employed to determine the path of motion of a point through a sequence of tag images depicting movement of the heart. The method may be employed to determine circumferential strain and radial strain.

An optical medium having a cavity that defines a variable gap is provided. The optical medium is used in an optical sensor, laser, and variable frequency resonator, by way of example. The cavity is physically altered in response to changes in a measurable parameter like pressure, temperature, force, flow rate, and material composition. The optical medium is characterized in some embodiments by having a cavity disposed near or within a high Q optical resonator. The optical resonator can be formed by various structures of which Bragg reflector cavities, ring resonators, microdiscs, and microspheres are examples. The optical resonator is preferably coupled to a laser source. The altering of the cavity affects the resonance condition within the optical resonator and thereby the laser signal of the system. If the laser source is a mode locked laser, the repetition rate of the pulse train changes in response to changes in the measurable parameter. If the laser source is a CW source the frequency of the laser signal is dependent upon a measurable parameter.

A three dimensional (3D) magnetic resonance imaging (MRI) system (100) performs object-induced geometric distortion correction. The MRI system performs (202) a 3D MRI pulse sequence to acquire a first 3D MR image of an examination region containing at least a portion of a subject and performs (202) the 3D MRI pulse sequence a second time to acquire a second 3D MR image of the examination region A computer system (110) computes (210) a voxel error map based on a phase difference between the first and second 3D MR images and corrects (212) voxel positions in one of the 3D MR images in accordance with the voxel error map.

A system for enhanced ratio control in a continuously variable transmission (CVT) includes a ratio control element positionable by an actuator in response to an actuator command to establish various CVT ratios in the CVT. At least one sensor generates a train of pulses indicative of speed of rotation of a predetermined rotary member of the CVT. A measured CVT ratio generator derives information of an actual CVT ratio out of at least the train of pulses to give a measured value of CVT ratio. A filter processes the measured value of CVT ratio in a manner to refine the information of the actual CVT ratio to give an estimated value of CVT ratio. A command generator determines the actuator command such that the actuator command remains unaltered when a deviation of the estimated value of CVT ratio from a desired value of CVT ratio stays within a dead zone. A filter and command generator manager narrows the dead zone to meet precision requirement upon determination that the desired value of CVT ratio has been accomplished and adjusts filter gain at the filter in a manner to keep amplitude at frequency of noise that is contained in the measured value of CVT ratio within the narrowed dead zone.

A device for detecting the position of a human finger or other object on a touch-sensitive scrolling pad. Dual independent oscillators may be used to generate two pulse trains at frequencies dependent upon the capacitance of two conductors resulting from the position of the finger on the conductors. The pulses from each oscillator may be counted over a time interval. A ratio-metric measurement may be taken by calculating the ratio of the two counts, and a sum may also be calculated. The ratio of the two counts relates to finger position on the device, and their sum relates to finger pressure upon the device.

A method of and an apparatus for an electro-optical distance measurement in which a laser beam of a laser diode (1) is directed as an intensity modulated train of emitted light pulses onto an object, the reflected measurement pulse train (10) is detected by a light detector (6), which generates, in response to the detection of a measurement pulse train, a first photo-current component, a smaller portion of the intensity modulated pulse train is branched out as a reference pulse train and, after passing a known reference path, is also detected by the light detector (6), which generates in response to this detection a second photo current component, and the light detector converts the measurement pulses, together with a mixer pulse train generated by a local oscillator, into a comparatively low-frequency IF-region that determines, after a corresponding conversion, the measured distance.

Fiber lasers and methods for constructing and using fiber lasers for micro- / nano-machining with output beams including stacked pulses and combinations of continuous wave, pseudo-continuous wave and pulse sequence components.

Operating range of feedback in CVT ratio control has been extended by use of stabilized values as an actual value of CVT ratio. The actual value of CVT ratio is derived from first and second pulse train signals provided by input and output speed sensors. Updating of rotational speed of the input member is repeated at intervals governed by the first pulse train. Updating of rotational speed of the output member is repeated at intervals governed by the second pulse train. Updating of an old value of a ratio between the latest value of the rotational speed of the input member and the latest value of the rotational speed of the output member to a new value thereof is repeated each time immediately after the rotational speeds of the input and output members have been updated since the latest updating of an old value of the ratio.