|| List of recent Fourier Transform-related patents
| System and method for constrained least-squares spectral processing and analysis of seismic data|
An inversion-based algorithm for computing the time frequency analysis of reflection seismograms using constrained least-squares spectral analysis is formulated and applied to modeled seismic waveforms and real seismic data. The fourier series coefficients are computed as a function of time directly by inverting a basis of truncated sinusoidal kernels for a moving time window.
| Lubrication with oil-compatible polymer brushes|
A polymer-brush-based, surface-modification strategy for friction and wear reduction in hard contact under boundary-lubrication conditions is proposed, specifically for a non-aqueous environment. Surface-initiated atom transfer radical polymerisation (si-atrp) was employed for the synthesis of three different oil-compatible, hydrophobic polymer brushes based on alkyl methacrylates.
| Optical communication transmitter system|
An optical transmitter may include a sample rate converter and a digital-to-analog converter operable to convert an inputted digital electrical signal to an analog optical signal. The signal converter may include a first interface operable to receive a digital electrical signal that may include a block of input data having n symbols in a time domain.
| Method for modulating an oqam type multi-carrier signal, and corresponding computer program and modulator|
A modulator and modulation method are provided, which output an oqam multi-carrier signal. The method implements a step of transforming, from the frequency domain to the time domain, a set of m symbols of real data so as to output m transformed symbols.
| Method for signaling information by modifying modulation constellations|
Methods and systems for communicating in a wireless network may distinguish different types of packet structures by modifying the phase of a modulation constellation, such as a binary phase shift keying (bpsk) constellation, in a signal field. Receiving devices may identify the type of packet structure associated with a transmission or whether the signal field is present by the phase of the modulation constellation used for mapping for the signal field.
| Apparatus for recording and reproducing hologram|
A hologram recording and reproducing apparatus including: a coherent light source; a beam splitter which splits a beam emitted from the coherent light source into a signal beam and a reference beam; a signal beam forming unit which modulates the signal beam split and directs the modulated signal beam onto a hologram recording medium; and a reference beam forming unit which directs the reference beam to be irradiated onto a location on the hologram recording medium which overlaps with a location on the hologram recording medium on which the signal beam is incident, wherein the signal beam forming unit includes: a first light guide member which transmits the signal beam split by the beam splitter; a spatial light modulator (slm) which modulates the signal beam transmitted through the first light guide member; and a holographic fourier transformation optical device which focuses the modulated signal beam onto the hologram recording medium.. .
| Fast transform based offset determination|
An offset estimator (e.g., a time delay, a spatial image offset, etc.) makes use of a transform approach (e.g., using fast fourier transforms). The sparse nature of a cross-correlation is exploited by limiting the computation required in either or both of the forward and inverse transforms.
|Decoding method and decoding device|
A discrete fourier transform circuit (201) calculates a first frequency spectrum in a predetermined frequency range from a detection signal in a predetermined segment. An expectation calculation circuit (202) calculates a second frequency spectrum corresponding to an expectation signal of a pattern of digital information that is present in the predetermined segment and obtained via an optical disc (100).
|Pattern test apparatus|
According to one embodiment, a pattern test apparatus includes a light source configured to apply test light to a test sample, a polarizing beam splitter which reflects or transmits the test light, an imaging device which receives light which has been reflected by the test sample and transmitted through or reflected by the polarizing beam splitter, an optical system which forms a fourier transform plane of the test sample between the test sample and the polarizing beam splitter, and a polarizing controller disposed in the fourier transform plane. The polarizing controller includes a first region which lets the test light through, and a second region which is greater than the first region and lets the light reflected by the test sample through, and the each regions have different retardation quantities..
|Method and device for range imaging|
A method for range imaging allows determining respective distances to multiple objects, based on a single image. The image is captured through a component having a transmittance function of which the fourier transform is inscribed on a circle within a plane of spatial frequencies.
|Ofdm speed estimation|
Techniques are provided for deriving speed estimates by performing a convolution of the output of the fast fourier transform (fft) stage from different time windows in an orthogonal frequency-division multiplexing (ofdm) modulation scheme. Such techniques enable speed estimation to be performed in the frequency domain, requiring little or no modification to existing ofdm systems..
|Direct sound extraction device and reverberant sound extraction device|
A direct sound extraction device includes: a spectrum transform unit that transforms an input signal, which includes a reverberant sound in a direct sound and on which a fourier transform process has been performed, to a first amplitude spectrum signal lfa; a low-pass filter unit (10) that performs a low-pass filtering process on the first amplitude spectrum signal lfa for each frequency to generate a second amplitude spectrum signal lfa1; a first subtraction unit (18) that calculates a third amplitude spectrum signal by subtracting the second amplitude spectrum signal lfa1 from the first amplitude spectrum signal lfa; and an inverse fourier transform unit that generates a direct sound signal lfd from a frequency spectrum signal calculated based on a phase spectrum signal and the third amplitude spectrum signal.. .
|Light extraction transparent substrate for organic el element, and organic el element using the same|
A light extraction transparent substrate for an organic el element includes a transparent supporting substrate; a diffraction grating having a first concavity and convexity layer having first concavities and convexities formed on a surface thereof, which is located on a surface of the transparent supporting substrate, and a microlens having a second concavity and convexity layer having second concavities and convexities formed on a surface thereof, which is located on a surface of the transparent supporting substrate. When a fourier-transformed image is obtained by performing two-dimensional fast fourier transform processing on a concavity and convexity analysis image obtained by analyzing the shape of each of the first and second concavities and convexities by use of an atomic force microscope, the fourier-transformed image shows a circular or annular pattern substantially centered at an origin at which an absolute value of wavenumber is 0 μm−1..
|Whitening filter configuration method, program, and system|
A system is configured so that signals passed through an all-pass filter using warp parameter λ are whitening-filtered, and so that the frequency axis is restored by an all-pass filter using warp parameter λ. This optimizes the whitening filter by determining the optimum λ.
|Method and system for burst formatting of precoded egprs2 supporting legacy user multiplexing|
A method and system for burst formatting of precoded epgrs2 supporting legacy user multiplexing, the method generating, at a transmitter, a burst containing a plurality of inverse discrete fourier transform (‘idft’) precoded symbols and plurality of non-idft precoded mid-amble symbols, wherein the idft precoded symbols are addressed for a first mobile device, and the non-idft precoded mid-amble symbols contain data addressed to a second mobile device.. .
|Mimo beamforming-based single carrier frequency division multiple access system|
A multiple-input multiple-output (mimo) beamforming-based single carrier frequency division multiple access (sc-fdma) system is disclosed. At the transmitter, a fast fourier transform (fft) is performed on transmission data to generate frequency domain data.
|Active sonar apparatus, active sonar signal processing method, and recording medium storing signal processing program thereof|
An active sonar apparatus which emits a sound wave and detects a target object based on a sound reflected by this target object including an fft part which performs the fast fourier transform of the received sound wave to derive a frequency spectrum and outputs this as an fft signal, a normalization part which normalizes the fft signal and outputs this signal as a normalized signal, and a noise elimination unit which performs a plurality of smoothing processes to the normalized signal, combines the signals to which the smoothing processes are performed to generate a combined signal, and outputs the combined signal in which a noise received together with the reflected sound is suppressed.. .
|System and method for correlating received signal over time and frequency|
A system is provided for use with a frequency band including a transmission frequency and a received frequency. The transmission frequency includes a transmission signal having a transmitted unique word therein.
|Multi-tap iq imbalance estimation and correction circuit and method|
A system (55-1) for correcting gain imbalance and phase imbalance between first (iout) and second (qout) signals which are 90° out of phase, including circuitry (32) for estimating the phase mismatch (φ) and gain mismatch (Δ) between the first signal and the second signal signals in a plurality of frequency bands. An inverse fast fourier transform is performed on each of a number of arrays of the phase mismatch estimates and the gain mismatch estimates to generate correction filter coefficients (h[n]) for a n tap correction filter (61).
|Apparatus and method for generating synchronization channel in a wireless communication system|
A synchronization channel (sch) transmission method includes generating a primary sch (p-sch) sequence according to supplementary information. The supplementary information includes at least one of base station (bs) type information, fast fourier transform (fft) size information, bandwidth (bw) information, group information, sector information, and carrier type information.
A novel imaging method, line-field holoscopy is presented. A line of light is projected across an object to be investigated through an imaging system.
|Method of extracting zero crossing data from full spectrum signals|
Methods and apparatus for using fourier techniques to detect and isolate the fundamental frequency sweep of echolocation calls produced by bats, or of other narrow-band whistles as produced by other kinds of animals such as birds and whales. According to one example, a fourier transform is applied on blocks of input samples to produce output frames, and a narrowband frequency modulated signal is detected and traced through the output frames.
|Asynchronous distributed computing based system|
An embodiment of the invention includes asynchronous data calculation and data exchange in a distributed system. Such an embodiment is appropriate for advanced modeling projects and the like.
|Image reconstruction from incomplete fourier measurements and prior edge information|
Systems and methods of image reconstruction that can reduce the number of fourier transform measurements required to obtain an exact or stable reconstruction of target images, using prior edge information obtained from a reference image. Full-sampled, 2 or 3-dimensional fourier transform measurements are obtained for the reference image prior to performing a time series study.
|Method and system for an ofdm joint training and frequency tracking system|
Aspects of a method and system for an ofdm joint timing and frequency tracking system may include tracking carrier frequency and symbol timing in an orthogonal frequency division multiplexing (ofdm) signal based on at least a reference symbol set. A receiver frequency and timing may be adjusted based on the tracked carrier frequency and symbol timing.
|Radio access method for reduced papr|
A wireless communication system is disclosed. A method for performing a radio access in the wireless communication system includes dividing an available frequency band into a plurality of subbands, generating a plurality of frequency domain sequences from a plurality of data symbol sequences by independently performing a fourier transform process in each of the subbands, independently mapping each of the frequency domain sequences to a corresponding subband, generating one or more transmission symbols by performing an inverse fourier transform process on the plurality of frequency domain sequences mapped to the available frequency band, and transmitting the one or more transmission symbols to a receiver..
|Transmitter, receiver and method for estimating variable frame structure using preamble signals|
A transmitter for estimating a variable frame structure using preamble signals is provided, and the transmitter includes a subcarrier location modulator configured to modulate locations of subcarriers into predetermined locations based on information about a variable frame structure in an attempt to transmit preamble signals; and an inverse fast fourier transform (ifft) unit configured to perform ifft on the preambles carried on the subcarriers of which locations are modulated and wirelessly transmit the preamble signals on which ifft has been performed.. .
|Fourier transform spectrometer and fourier transform spectroscopic method|
A fourier transform spectrometer (da) of the invention extracts, in generating an integrated interferogram obtained by integrating a plurality of interferograms, an output of an interferometer (11a) within a predetermined range according to positioning information of a center burst in an interferogram measured at a time before measurement of an interferogram at the present time.. .
|Method and system for multiple training sequences for peak-to-average power ratio reduction in precoded bursts|
A method and apparatus for peak to average power ratio reduction, the method precoding the data symbols using an inverse discrete fourier transform (‘idft’), choosing, at a transmitter, a set of training sequence symbols from a plurality of sets of training sequence symbols, and creating, at the transmitter, an idft precoded burst by adding the idft of the data symbols and an idft of the chosen set of training sequence symbols. Further, a method and receiver, the method receiving a burst, performing a discrete fourier transform on the burst, choosing a training sequence among a known plurality of training sequences sets, the chosen training sequence resulting in the least noise estimate among the plurality of training sequence sets, and demodulating the burst with the detected pilot burst..
|Multi-user detection using equalization and successive interference cancellation|
A method and apparatus for multi-user detection is disclosed. A signal is received in a shared spectrum, and samples of the received signals are produced as a received vector.
|Medical image display system|
A medical image display system is shown. The medical image display system includes, a fringe scanning type capturing apparatus or a fourier transformation type capturing apparatus; an image processing section; a display section; and a control section.
|Apparatus for transmitting and receiving data to provide high-speed data communication and method thereof|
In the present invention, data generated from a source unit are distributed to at least one bandwidth; the data distributed to the respective bandwidths are encoded in order to perform an error correction; the encoded data are distributed to at least one antenna; a subcarrier is allocated to the data distributed to the respective antennas, and an inverse fourier transform is performed; a short preamble and a first long preamble corresponding to the subcarrier are generated; a signal symbol is generated according to a data transmit mode; and a frame is generated by adding a second long preamble between the signal symbol and a data field for the purpose of estimating a channel of a subcarrier which is not used.. .
|Combined echo and crosstalk cancellation|
Combined echo and crosstalk cancellation is provided. Frequency domain adaptive filters are used to remove or reduce the effects of echo and crosstalk for a multi-channel and full-duplex communications system.
The present invention provides an inspection apparatus having a high throughput and high sensitivity with respect to a number of various manufacturing processes and defects of interest in inspection of a specimen such as a semiconductor wafer on which a pattern is formed. The apparatus illuminates with light the specimen having the pattern formed thereon, forms an image of the specimen on an image sensor through a reflective optics, and determines the existence/nonexistence of a defect.
|Computer-implemented system and method for user-controlled processing of audio signals|
A computer-implemented system and method for user-controlled processing of audio signals is provided. An audio signal including a reference segment and a segment preceding the reference segment is obtained.
|Method of determining the breaking stress in shear of a part of determined thickness|
A method of determining the breaking stress in shear for a part of determined thickness and made up of two elements that are bonded together by a layer of adhesive. A plane sensor emits an ultrasound wave at the part of determined thickness.
|Communication device and communication method|
A modulator performs a predetermined operation for making an absolute value of an operation result of at least one element of an input signal greater than 0 on the individual elements of the input signal. The modulator generates post-operation data by associating individual elements of the input signal with individual elements of a data series which is a set of pieces of data which are equal in number to the elements of the input signal and whose absolute values are equal to one another, and multiplying the individual elements of the input signal which are subjected to the predetermined operation by the elements of the data series.
|Synthetic hologram reading device and method|
The present invention involves a device for reading the source image of a synthetic hologram constituting the fourier transform of the source image formed on a support (40), comprising a lens (42) positioned for forming the fourier transform of the hologram on an image detection system (44), the relative positions of said lens and of said support being selected so that a desired number of replicas of the image are displayed on a plane of the detection system, said device further comprising a processing system (48) capable of performing a combination of replicas of the image.. .
|Software program for monitoring a hand tremor of an end-user via a computer mouse input device|
A computer receives movement information, wherein the movement information is sent by a computer mouse input device in response to an end-user moving the computer mouse input device. The computer determines a frequency at which an end-user typically tremors based on the movement information received during a specified time interval, by utilizing a fast fourier transform operation.
|Technique for transmitting on multiple frequency resources in a telecommunication system|
The present disclosure relates to a technique for transmitting modulation symbols on multiple frequency resources. A method aspect of this technique includes applying a discrete fourier transform (dft) coding per set of modulation symbols of two or more sets of modulation symbols, wherein a first set of modulation symbols from the two or more sets of modulation symbols is transmitted on a set of frequency resources handled by the same power amplifier.
A method of antenna array processing. Digitized time-series data from a plurality of antenna elements are divided into a plurality of time windows.
|Processing of signals to provide a delay doppler map|
An apparatus is disclosed for processing a sequence of samples of a received signal r reflected by a target surface and having a delay and a frequency shift relative to a reference signal d to obtain a delay doppler map for the reflected signal. A first correlation module can obtain partial correlations z(n′, k) between samples corresponding to the reflected signal r and a samples corresponding to the reference signal d, across a set of delays.
|Method and apparatus for efficient frequency-domain implementation of time-varying filters|
Embodiments are directed to efficient frequency-domain implementations of time-varying fir filters. More specifically, time-varying fir filters according to embodiments exploit the duality of the fast fourier transform that windowing in the time domain equals convolution in the frequency domain.