51 results about "Coherent wave" patented technology

The invention discloses a single-snapshot data-based coherent signal DOA estimating method and relates to the technical field of array antenna systems or methods capable of indicating different signal directions. The method comprises rearranging the single-snapshot received data of an array to obtain two pseudo-covariance matrixes, and then through two pseudo-covariance matrixes, expanding the covariance matrix of a subspace restructuring algorithm; performing singular value decomposition on the new pseudo-covariance matrixes to obtain a signal subspace and a noise subspace, and performing DOA estimation on incoming coherent wave signals through a MUSIC spectrum estimating method. The single-snapshot data-based coherent signal DOA estimating method can eliminate coherence among source signals under single-snapshot conditions and meanwhile further improve the DOA estimating precision. The single-snapshot data-based coherent signal DOA estimating method is mainly applied to rapid estimation of incoming directions of coherent signals under the single-snapshot conditions.

Coherent wave noise energy is removed from seismic data by modeling both the P-wave primary energy and the coherent wave noise energy. The P-wave primary energy is modeled first and then subtracted from the input data. The data with the P-wave primary energy removed is used as the input for coherent wave energy removal. The coherent wave energy is modeled and subtracted from the original input data, i.e. the data input into P-wave primary removal. This leaves a dataset with P-wave primary energy and noise energy not related to coherent waves. This method can be utilized to remove all types of coherent noise with a velocity difference to the desired P-wave primary energy or with a different type of moveout (change of time of arrival with source-receiver distance) such as, for example, linear moveout.

The invention provides a life form detection processing method and apparatus, and a terminal. The method comprises the following steps: emitting WiFi electromagnetic waves; receiving coherent waves of reflection waves of the WiFi electromagnetic waves and the WiFi electromagnetic waves; and according to the received coherent waves, determining life form information. According to the invention, the problems of inconvenient user operation, low popularization rate and low versatility existing in life form detection in related arts are solved, and the effects of high portability, easy use and timely use are achieved.

A system and method for providing coherent sources for phased arrays are provided. One method includes providing a plurality of transceivers configured to transmit signals and defining an array of nodes. The method also includes providing a plurality of beacons at different frequencies to one of aim or focus phase coherent energy generated by the transmitted signals from the plurality of transceivers, wherein the phase coherent energy is transmitted at a direction and a frequency determined with phase conjugation and independent of the location of the plurality of beacons.

Coherent wave noise energy is removed from seismic data by modeling both the P-wave primary energy and the coherent wave noise energy. The P-wave primary energy is modeled first and then subtracted from the input data. The data with the P-wave primary energy removed is used as the input for coherent wave energy removal. The coherent wave energy is modeled and subtracted from the original input data, i.e. the data input into P-wave primary removal. This leaves a dataset with P-wave primary energy and noise energy not related to coherent waves. This method can be utilized to remove all types of coherent noise with a velocity difference to the desired P-wave primary energy or with a different type of moveout (change of time of arrival with source-receiver distance) such as, for example, linear moveout.

A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface. The guide tip is further adapted to be placed against the tissue surface with the guide tip slidable along the tissue surface in atraumatic sliding engagement with the discharge bore opposing the tissue surface. The lesion formation tool is manipulated to draw the guide tip over the tissue surface in a pathway while maintaining the discharge bore opposing the tissue surface to form a transmural lesion in the tissue extending a length of the pathway.

A coherent radiation imaging system that produces digital images with a reduced amount of speckle. Radiation from a long coherence length source is used to form an image of a sample. The output coherent wave is temporally divided into a plurality of wavelets. The spatial phase of each wavelet is then modulated a known and different amount. Each phase modulated wavelet illuminates the sample and is perturbed by its interaction with the sample. A spatial phase map of each perturbed wavelet is then created and converted to a sample image with an image reconstruction program. The plurality of sample images thus formed is statistically averaged to form a final averaged image. The high frequency speckle that is not optically resolvable tends to average to zero with continual statistical averaging, leaving only the optically resolvable lower frequency phase information.

Disclosed is a method for producing a surface structure which is antireflective for a wavelength range with a minimal wavelength lambdaM, having a supporting coat on which a light-sensitive material is applied which is exposed with at least two mutually coherent wave fields with a wavelength of lambdaB in order to obtain a stochastically distributed interference field, whereby during or after exposure, said surface structure is formed by means of selective removal of materials. The invention is distinguished by mutually interfering, coherent wave fields directed at the light-sensitive coat of material forming an angle alpha, for which applies: alpha>2 arcsin(lambdaB / (2.lambdaM))

The invention belongs to the field of electromagnetic wave and novel artificial electromagnetic materials and particularly relates to a dynamically tunable broadband polarization converter, comprising a dielectric layer and a novel artificial electromagnetic material layer. The novel artificial electromagnetic material layer is located on the surface of the dielectric layer, wherein novel artificial electromagnetic material is square diagonal split rings arranged periodically, and the novel artificial electromagnetic material is of sub-wavelength structure; dynamical tunability is based on the principle of coherent control and is finished through two coherent waves, namely a signal wave and a control wave, the two waves have the same amplitude and wavelength and propagate face to face in a direction perpendicular to the novel artificial electromagnetic material, and a phase difference between the signal wave and the control wave is changed. The converter has the advantages of portability, light weight, ease of integration and the like and is of single layer, small thickness, light weight and conformal proneness when compared with a traditional polarization conversion material.

A coherent radiation imaging system that produces digital images with a reduced amount of speckle. Radiation from a long coherence length source is used to form an image of a sample. The output coherent wave is temporally divided into a plurality of wavelets. The spatial phase of each wavelet is then modulated a known and different amount. Each phase modulated wavelet illuminates the sample and is perturbed by its interaction with the sample. A spatial phase map of each perturbed wavelet is then created and converted to a sample image with an image reconstruction program. The plurality of sample images thus formed is statistically averaged to form a final averaged image. The high frequency speckle that is not optically resolvable tends to average to zero with continual statistical averaging, leaving only the optically resolvable lower frequency phase information.

The invention provides an active and passive ultrasonic composite imaging method and system for focused ultrasonic irradiation on phase change nanometer liquid drops. After passive ultrasonic originalradio frequency signals are subjected to time delay compensation processing, a cross-correlation coefficient matrix and a passive amplitude coherent wave beam forming energy matrix are obtained respectively through two complementary square wave apodizing functions and an amplitude coherent coefficient; after the two matrixes are subjected to point multiplication, a high-resolution passive ultrasonic imaging result is obtained; phase change microbubble group mother wavelets are constructed through a phase change microbubble group vibration model; active wave beam forming radio frequency signals obtained after the mother wavelets are used for performing time delay superposition on the active ultrasonic original radio signals are subjected to continuous wavelet transformation to obtain a high-contrast active ultrasonic imaging result; and a composite image is obtained after the high-resolution passive and high-contrast active ultrasonic imaging results are compounded. The method and thesystem can be used for performing whole-process monitoring on cavitation activities in the focused ultrasonic irradiation process of the phase change nanometer liquid drops and the residue phase change microbubbles when the irradiation is stopped.

The invention is a phase unwrapping method to process coherent waves. The feature is: first to do vector filter on the phases containing remnant pixel, then to unwrap phases with reliability phase unwrapping method. The mentioned vector filter is to compute sine and cosine value of each pixel in the phase, and perform the average filtering on the continuous sine and cosine images, finally obtain the phase value of filtered interference image by inverse mapping; then wrap the phases with reliability phase unwrapping method: first construct the reliability, then wrap the phases in order according to the value of reliability.

The invention discloses a PWM (pulse-width modulation) module which is applied to a flyback type switching power supply topology, can cause reverse voltage of D-S two ends of the topology to be lower and can always alternatively generate an interruption mode and a critical mode. The PWM module comprises a PWM control circuit and a sawtooth generator, and further comprises a zero current detection and start synchronizing circuit and a load weight sawtooth wave frequency conversion circuit, wherein the PWM control circuit is used for switching off fixed clock start peak current; the zero current detection and start synchronizing circuit can generate phase coherent waves; after the coherent waves and sawtooth waves are iterated, the PWM control circuit can start another alternative PWM signal output; and when a flyback circuit works in a current continuous mode, the sawtooth waves work under different frequencies by the load weight sawtooth wave frequency conversion circuit. According to the PWM module disclosed by the invention, the flyback circuit always works in a current interruption mode and critical mode alternatively generating state; the reverse voltage generated by the D-S two ends of a switching tube is reduced to 1.2-1.5 times of power source voltage; and the PWM module has a simple structure, the controlled flyback topology switching on-off loss is small, the service life is long and a few of ultraharmonics are generated.

Methods and systems are provided to form a single coherent beam of light from a plurality of smaller beams of light. In one implementation a beam combiner comprising a beam director is configured to direct a seed beam of coherent light and a plurality of pump beams of coherent light; and a nonlinear converter is configured to combine the seed beam and the plurality of pump beams directed by the beam director to produce a substantially coherent wave front.

The invention provides a denoising method and device for a brake system. The denoising method for the brake system comprises steps as follows: acquiring noise signals; screening the noise signals, and obtaining a low-frequency brake noise signal; analyzing the low-frequency brake noise signal, and generating a denoising signal coherent with the low-frequency brake noise signal according to coherent wave coherent conditions; playing the denoising signal. According to the technical scheme, an active denoising technology is adopted, low-frequency brake noise can be effectively reduced in the principle of sound wave interference, and the noise optimizing period is short.

The invention discloses a water-based interlayer metasurface adjustable coherent wave absorber. The water-based interlayer metasurface adjustable coherent wave absorberis of a novel structure and achieves real-time dynamic adjustment of frequency and amplitude of a coherent absorption peak and regulation and control of absorption channel regularity of incident coherent wave beams in different polarization states through low-cost materials. Micro-units are periodically arranged to form an overall structure of the water-based interlayer metasurface adjustable coherent wave absorber, each micro-unit is of a sandwich structure formed by a PCB substrate with double-opening split resonance ring metal patterns etched on the two sides, and a water intermediate dielectric layer, and the water layer and the substrate are equal in length and width. By adjusting the relative orientation of the openings of the resonant rings on the two sides of each micro-unit, complete coincidence and separation of incident coherent wave absorption channels in different polarization states are achieved, and the method has important application value in frequency filtering and polarization selective permeability. By changing the phase difference between the water temperature and the incident coherent wave beam, the wave absorbing characteristics such as the absorption frequency point and the absorption rate can be dynamically regulated and controlled in real time, and the regulation and control capability of the coherent wave absorber is improved.

The invention relates to a maritime radio communication monitoring and direction finding system which is characterized by comprising a vertical polarization monitoring and direction finding antenna array, a five-channel signal switching module, an amplification module, a five-channel receiver, a digital signal processor (DSP) processing module, a computer, a monitoring and direction finding controller, a 3rd generation (3G) antenna, a radio station antenna, a 3G router, a digital broadcasting station, a switchboard, an electronic compass, a global positioning system (GSP) module and a GSP antenna. The maritime radio communication monitoring and direction finding system has the advantages that: an interfering signal can be monitored better due to the working frequencies ranging from 30 to 500MHz; simultaneous direction finding of several coherent waves is realized; simultaneous direction finding and ultrahigh-resolution digital direction finding of transmitting signals with same frequency and different directions are realized; direction finding of digital frequency hopping, a spread spectrum and a burst signal is realized; monitoring and measuring on different frequency domains, different time domains and different modulation domains can be simultaneously performed during measuring due to respective local oscillation of five channels; the problem of cross coupling among all antenna array elements is solved; the coupling and the phase ambiguity among unit antennas are removed; and dynamic application ranges of received signals are expanded.

The invention discloses an audio playing device and a mobile terminal. The audio playing device comprises at least two loudspeakers, wherein sound waves sent by each loudspeaker are coherent waves, a phase difference of the sound waves which are sent by any two loudspeakers and arrive at a first target region is an integer multiple of 2pi, and the phase difference of the sound waves arriving at a second target region is an odd number of pi. Therefore, the coherent phase of the sound waves sent by the loudspeakers in the first target region is long, the sounding power of each loudspeaker is superimposed efficiently, the loudness of the sound in the target region is improved, the sound effect of the region is enhanced greatly, consequently, the peak power of single loudspeaker can be reduced, the user experience is improved, and the energy is saved. The coherence of the sound waves sent by the loudspeakers is cancelled in the second target region, so that the sound in the target region is suppressed, directional propagation of the sound is realized, avoiding of accidental leakage of information is benefited, privacy of a user is protected, and meanwhile other persons are also prevented from being disturbed.

An adaptive optics system comprises a beamsplitter configured to divide an incoming beam with an aberrated wave front into a first input beam and a second input beam, a microelectromechanical system configured to reflect the first input beam onto an image plane, and a self-reference wave front generator configured to spatially filter the second input beam to form a reference beam, and to interfere the reference beam with the first input beam on the image plane to form a hologram. The system further comprises an imaging device configured to capture an image of the hologram on the image plane, and one or more processors. The one or more processors are configured to perform the steps of Fourier transforming the captured image to generate a transform including a first object image, a conjugate object image, and an auto-correlation image, truncating the transform to exclude the conjugate object image and the auto-correlation image, inverse Fourier transforming the truncated transform to generate amplitude and phase information about the aberrated wave front, generating control signals for mitigating aberrations in the aberrated wave front via phase conjugation based on the amplitude and phase information, and providing the control signals to the microelectromechanical system.

The present invention employs one or two radiation arrays to motivate a higher-mode TEn0 mode (n is an integer larger than or equal to 2) as much as possible at the front portion, the rear portion orthe upper portion of a heating cavity of a transversely uniform microwave oven so as to form standing waves in the heating cavity. The at least one radiation array comprises at least two lines of radiators in a Z direction. The at least one radiation array radiates the microwave energy to the heating cavity through a floor. The radiators on any one radiation array are uniformly distributed in theX direction and the Z direction. The radiated microwaves in all the radiators on the same radiation array are coherent waves. In order to further improve the heating uniformity, a rotary table with transverse translation or processing around a vertical axis of the heating cavity is employed. The microwave mode in the cavity of the transversely uniform microwave oven is controlled to improve the heating uniformity of the transversely uniform microwave oven in the three-dimensional space.

The invention discloses a wave steep function component judgment-based sea wave number spectrum reconstruction method. The method comprises the following steps that: each Doppler spectrum is estimatedby adopting a spectral moment method to obtain central frequencies; the obtained central frequency sequence is converted into a speed sequence, primary Fourier transform is performed to obtain a speed spectrum, and the speed spectrum is multiplied by an analytic function to obtain an original sea wave number spectrum; a judgment threshold is determined by adopting a wave steep function componentjudgment criterion, the right side of the judgment threshold of the wave number spectrum is a stormy wave component, and the left side of the judgment threshold is a non-stormy wave component; effective wave height and full-spectrum peak energy P2 are calculated according to a wind speed simulation PM wave number spectrum; if peak energy P1 is smaller than the peak energy P2 of a stormy wave system on the right side of the original spectrum, the non-stormy wave component on the left side of the threshold is replaced with the corresponding part of the Gauss wave number spectrum; and if the PM peak energy P1 is greater than the PM peak energy P2, the non-stormy wave component on the left side of the threshold is replaced with a corresponding part of the PM wave number spectrum. The sea waveinversion precision of a coherent wave-measuring radar can be improved. The method is suitable for shore-based and shipborne microwave Doppler radar systems of various coherent systems.

A phase-shift holographic device based on a phase-type vortex lens and an imaging method are disclosed. The device comprises a light source, a beam splitter, a rotating lens frame, a phase-type vortexfocusing lens, a collimating lens, a first reflecting mirror, a beam combiner, a first three-dimensional translation stage, an imaging detector, a computer, a second reflecting mirror, a second three-dimensional translation stage and a measured object. The phase-type vortex focusing lens used in the invention can be used for a coherent wave band from visible light to a Terahertz wave band. In theinvention, the space-bandwidth product of the imaging detector can be fully used, the accurate reproduction of the measured object can be rapidly realized, the conjugate image of a reproduction result can be effectively restrained, and the reproductive image quality of the measured object can be obviously increased.

The invention discloses a broadband high-sensitivity millimeter wave receiving system based on carrier suppression, which is characterized in that a dual-wavelength generation structure based on carrier suppression comprises that a single-tone signal generated by a microwave source directly drives an intensity modulator, and the intensity modulator works at a carrier suppression point to generate two coherent wave beams; a microwave photon down-conversion structure based on the intensity modulator comprises the following steps: modulating a radio frequency carrier signal to a beam of light wave in a carrier suppression dual-wavelength generation structure by using the intensity modulator, and keeping a-1-order sideband by using fiber bragg grating filtering; and a homodyne coherent detection unit which is used for performing homodyne coherent detection by using the other light wave beam generated by the carrier suppression dual-wavelength generation structure and a-1-order sideband output by the microwave photon down-conversion, so as to realize photoelectric conversion and complete demodulation from the millimeter wave radio frequency signal to the baseband signal. According to the invention, down-conversion of any millimeter wave radio frequency signal is realized, large-capacity and long-distance transmission of millimeter wave wireless communication is supported, the principle is simple, and the application value is high.

The disclosure relates to the field of holographic technology, and specifically provides a method for manufacturing an interference fringe mold and a mold and replication method thereof. The method comprises the following steps: (1) composite coherent wave sensitive material on the surface of a three-dimensional mold; (2) record interference fringes through a three-dimensional optical path, so that the composite sensitive material layer of the three-dimensional mold is loaded with interference fringes; the recording method of the three-dimensional optical path is as follows: The characteristics of recording information content Set up a suitable three-dimensional space optical path, and record information on the sensitive material layer according to requirements; (3) Repeat the three-dimensional mold with interference fringes for multiple inverse copies, and finally obtain an interference fringe mold with a certain hardness. It solves the problems in the prior art that the holographic illusion pattern is deformed or disappears due to the deformation of the plane template into a three-dimensional template to copy interference fringes, and the copied holographic illusion image has only a single viewing direction and a narrow viewing angle.

Provided in the embodiments of the present application are a network node and an up-and-down wave unit, used to reduce a cost of a coherent division multiplexing network system. The embodiments of the present application comprise: a receiver, a first up-and-down wave node, and a first centralized wave lock module; the first up-and-down wave node is connected to the first centralized wave lock module; the first up-and-down wave node comprises a first input port, a first wave-selection port, a first pass-through port, a first output port, and a first up-and-down wave port; the first up-and-down wave port and the first wave-selection port have a same filter window. The receiver comprises: a first tunable laser module, a 90 degree optical mixer Hybrid, and a first optical splitter; the first optical splitter is connected to the 90 degree Hybrid; the first tunable laser module, the first optical splitter, the first up-and-down wave node, and the first centralized wave lock module are connected successively; a light wave emitted by the first tunable laser module is sent to the first centralized wave lock module by means of the first wave-selection port so as to generate a first target light wave c which has a same wavelength as a second target optical signal.

The invention discloses a ship attitude motion component removal method based on spatial displacement. The method comprises the following steps of: establishing an expression of comprehensive Dopplerfrequency shift measured by a shipborne coherent radar; calculating six-degree-of-freedom ship motion amplitude response factors on the basis of sea wave frequency component distribution characteristics according to the style data of a ship body under the condition that the ship body is excited by waves of a unit wave height; based on a sea wave frequency spectrum measured by the radar at the lastmoment, obtaining the fluctuation rule of a ship by constructing a wave surface equation of a regular sea surface, and then obtaining the sea surface wave height displacement of the position of the ship body; performing six-degree-of-freedom coordinate conversion under an earth coordinate system and a ship coordinate system; calculating the spatial displacement of a radar antenna in a time periodaccording to the space coordinate difference between a previous moment and a next moment; finally solving the additional Doppler frequency shift caused by the attitude motion component of the ship body, and removing the component from the radar echo Doppler frequency shift. The method can effectively improve the extraction effect of the radial velocity of real water quality points of sea waves, and improves the precision of coherent wave-measuring radar sea wave parameter inversion.

The invention provides an active and passive ultrasonic composite imaging method and system for focused ultrasonic irradiation on phase change nanometer liquid drops. After passive ultrasonic originalradio frequency signals are subjected to time delay compensation processing, a cross-correlation coefficient matrix and a passive amplitude coherent wave beam forming energy matrix are obtained respectively through two complementary square wave apodizing functions and an amplitude coherent coefficient; after the two matrixes are subjected to point multiplication, a high-resolution passive ultrasonic imaging result is obtained; phase change microbubble group mother wavelets are constructed through a phase change microbubble group vibration model; active wave beam forming radio frequency signals obtained after the mother wavelets are used for performing time delay superposition on the active ultrasonic original radio signals are subjected to continuous wavelet transformation to obtain a high-contrast active ultrasonic imaging result; and a composite image is obtained after the high-resolution passive and high-contrast active ultrasonic imaging results are compounded. The method and thesystem can be used for performing whole-process monitoring on cavitation activities in the focused ultrasonic irradiation process of the phase change nanometer liquid drops and the residue phase change microbubbles when the irradiation is stopped.