147 results about "Wave separation" patented technology

A optical fiber gas sensor employs a optical fiber Fabry-Perot interferometer constituting a low reflection cavity lens and a measurement optical fiber to detect sound pressure wave signal generated by gas after absorbing light energy, and a realization method for optical acoustic gas sense technique is provided. Pulse modulated excited light is emitted by an excitation light source, passes through a band-pass filter and enters a gas cavity from a gas cavity window; the excited light emitted into the gas cavity generates a sound pressure wave which strength corresponds to measured gas concentration in the gas cavity after absorbing by the measured gas; the sound pressure wave is transmitted to vibration of a vibrating film sheet by the vibrating film sheet which is equipped at other end of the gas cavity; a measuring light signal emitted by measuring light source driven by a first drive power supply passes through a optical fiber wave combination equipment, a transmission optical fiber and a optical fiber wave separation equipment and enters a measuring optical fiber of the Fabry-Perot interferometer; concentration value of the measured gas is obtained by optical path difference of the return light beam and the light beam directly reflected by an optical end face.

An apparatus and a method that achieve physical separation of sound sources by pointing directly a beam of coherent electromagnetic waves (i.e. laser). Analyzing the physical properties of a beam reflected from the vibrations generating sound source enable the reconstruction of the sound signal generated by the sound source, eliminating the noise component added to the original sound signal. In addition, the use of multiple electromagnetic waves beams or a beam that rapidly skips from one sound source to another allows the physical separation of these sound sources. Aiming each beam to a different sound source ensures the independence of the sound signals sources and therefore provides full sources separation.

The invention relates to a diffracted wave separation processing method based on reflection wave layer leveling extraction and elimination. The diffracted wave separation processing method comprises the following steps that (1) the processing is carried out; (2) the CDP (common depth point) gather record in the preprocessing is subjected to dynamic correction and static correction processing, and the shot gather record is generated according to trace header information; (3) the target level picking is carried out according to superposition data, the level leveling time quantum is extracted, and the level leveling time information is reflected onto each trace record in the prestack shot gather record according to the relationship of each trace record in the CDP and shot gather record; (4) the reflection wave layer leveling processing of the prestack shot record is carried out according to the level leveling time quantum; (5) the reflection wave layer leveling shot gather is recorded, reflection waves are extracted and are subtracted from original records, and the diffracted wave shot record is obtained; (6) the diffracted wave shot record is subjected to reverse leveling processing; (7) the shot gather record is withdrawn to the CDP gather record, and the superposition processing is carried out; and (8) the velocity field obtained through velocity analysis is subjected to migration processing, and diffracted wave migration imaging result data is obtained.

The invention discloses a pile foundation quality detection method and device. The method comprises: connecting an output signal of an about-10cm interval geophone string formed by micro-speed or acceleration sensors with a multichannel synchronization elastic wave acquirer (3) by a signal cable (2); removing laitance on a pile head of a pile foundation (4), cleaning the pile head, and forming a detection hole (5) axially parallel to the pile foundation at the center of the pile head by a drilling machine, wherein the hole diameter is about 50cm and the hole depth is about 1m; placing the geophone string along the detection hole, and enabling geophones to be tightly attached on the wall of the detection hole by a machine or an inflation air bag (6); exciting elastic waves in modes of hammering (7) on the pile head and the like, recording elastic wave response signals by the multichannel synchronization elastic wave acquirer (3) through the signal cable, and repeatedly hammering to form signal superposition; and performing travelling wave separation on upward travelling waves and downward travelling waves in multichannel elastic wave response signals, pressing or filtering the downward travelling waves, reserving the upward travelling waves for reflecting defect reflected signals of the lower part of the pile foundation, and performing excursion superposition according to the correlation of the defect reflected upward travelling signals to form reflected signals excited and received on the pile top surface, thus obtaining positions and properties of defects at the lower part of the pile foundation. In the detection method, reliability of interpreting and extracting defect reflected signals in pile foundation detection is improved by comprehensive technologies of multiple excitation signal superposition, multi-sensor signal travelling wave separation, correlated reflected signal excursion superposition and the like, thus improving reliability of detection results.

The invention is a tunable wavelength selecting / locking optical dense wave division multiplex wave combining / separating device, including an input port and eight wave separation output ports, two wavelength tuning selection combining components, and the wavelength locking control structure includes optical-fiber coupler, optical FP etalon, fast wavelength tuning filter, two fast photoelectric conversion probes, and differential amplifier tracking signal processor. The wavelength locking control structure collects and processes two optical signals of a primary optical path and controls the wavelength tuning selection combining components in the primary optical path by circuit feedback. The wavelength tuning selection combining components are packaged with many optical resonance cavities in parallel on an optical shared surface, adopt the electrooptical effect of electrooptical polymer film and the multi-reflection coherence theory of optical resonance cavities to form tuned filtering characteristic, making the output of each wave separation port of the multiplexer meet the design requirements on wavelength selection and wideband tuning, and it makes locking control on the central wavelength of each channel, stable and reliable.

The invention provides an earthquake diffracted-wave separation method and device and relates to the technical field of earthquake exploration. The method comprises the steps that earthquake shot gather data carrying underground geological information in a preset geological area is obtained; single-shot preprocessing data obtained by preprocessing the earthquake shot gather data and a preset migration velocity model are input into a three-dimensional single-shot angle-domain imaging formula, wave field opposite-transmission processing is conducted on the earthquake shot gather data to obtain azimuth angles, emergence angles and amplitude information of propagation rays corresponding to underground imaging points in the preset geological area in a one-to-one mode; according to the azimuth angles, emergence angles and amplitude information of the propagation rays, a three-dimensional single-shot angle-domain imaging matrix is generated; low-rank matrix components are separated out of the three-dimensional single-shot angle-domain imaging matrix through a preset three-dimensional diffracted-wave separation model, and the low-rank matrix components are determined as earthquake diffracted waves. The integrity and waveform consistency of separated diffracted-wave amplitude are improved, and further the resolution ratio of geological structure imaging is improved.

The invention discloses a full-waveform inversion method for VSP seismic data converted waves. Uplink PS converted waves are separated through a global optimization parameter inversion method; transverse wave speed is claculated according to an empirical formula, and is subjected to smoothing processing to obtain an initial transverse wave speed model; an elastic wave equation of longitudianl andtransverse wave separation is solved to obtain a forward propagation longitduinal and transverse wave field and simulated VSP PS wave record of each time step; an accompanying elastic wave equation oflongitudinal and transverse wave separation is solved to obtain back propagation longitduinal and transverse wave field of each time step; a forward propagation longitudinal wave field and a back propagation transverse wave field are adopted to calculate a transverse wave speed gradient; a three-point parabola fitting method is adopted to obtain an iteration step size; a transverse wave speed model is updated through an L-BFGS method; and multi-scale inversion is performed from low frequency to high frequency by applying Wiener filtering. The full-waveform inversion method for VSP seismic data converted waves has the beneficial effect of improving the precision of the full-waveform inversion of the VSP seismic data converted waves and improving an inversion effect of a complex structure through a longitudinal and transverse wave separation strategy.

The invention belongs to the field of seismic signal processing in seismic exploration technologies, and specifically discloses a primary wave and multiple wave separation method based on an alternative splitting Bregman iterative algorithm. With regard to a multiple wave self-adaptive subtraction method based on a 3D matched filter, the primary wave and multiple wave separation method utilizes the alternative splitting Bregman iterative algorithm to solve an optimization problem of applying sparsity constraint on primary waves, achieves the estimation of the 3D matched filter, and utilizes the estimated 3D matched filter to separate the primary waves and the multiple waves in a 3D data window in a self-adaptive manner. Compared with the traditional iterative reweighted least squares algorithm, the alternative splitting Bregman iterative algorithm adopted by the primary wave and multiple wave separation method only needs to calculate matrix-matrix multiplication and matrix inversion once when estimating the 3D matched filter at each 3D data window, can effectively reduce the calculation complexity of solving the optimization problem, and improves the calculating efficiency of primary wave and multiple wave self-adaptive separation.

The invention discloses an acoustic covering layer echo reduction measuring method on the basis of a multichannel space-time inverse filtering technology. The method comprises the following steps: (1) generating a single channel space-time inverse filtering emission signal; (2) generating a multichannel space-time inverse filtering emission signal; (3) collecting a sample echo signal and an incident signal; (4) calculating the echo reduction measured value. By synchronously emitting the inversion signals of a circuit channel and underwater acoustic channel and multichannel inversion signals, the focusing of measuring signals in the space and time-domain pulse compression can be achieved, and the goals of reverberation inhibition, direct path wave separation, and multiple times of echoes of a multilayer sample can be realized.

The invention provides a single-phase electric energy metering chip. The single-phase electric energy metering chip comprises a full-waveform module which is connected with a sampling and analog-to-digital conversion module, a fundamental wave separation module which is connected with the full-waveform module, an effective value calculation module which is connected with the full-waveform module and the fundamental wave separation module, an active power calculation module which is connected with the full-waveform module and the fundamental wave separation module, a reactive power calculation module which is connected with the full-waveform module and the fundamental wave separation module, an apparent power calculation module which is connected with the effective value calculation module, a power factor calculation module which is connected with the apparent power calculation module and the active power calculation module, an Nth-degree harmonic separation calculation module, and an energy calculation module. The single-phase electric energy metering chip can flexibly choose the calculation of the active power, the reactive power, the apparent power and the power factor of full-wave, fundamental wave and each harmonic and the electric energy metering of active, reactive and apparent energy.

The invention provides a method for separating variable offset vertical seismic profile (VSP) wave fields. The method comprises the following steps of: inputting the collected original seismic wave field data of the variable offset VSP in a computer; performing t2 stretching treatment on the original seismic wave field data to form t2 stretching processing data; performing discrete positive parabolic radon transformation on the t2 stretching processing data to form tau-q domain up-going wave separation data and tau-q domain down-going wave separation data; performing discrete reverse parabolic radon transformation on the tau-q domain up-going wave separation data and the tau-q domain down-going wave separation data to form x-t2 domain data; and performing reverse t2 stretching treatment on the x-t2 domain data to separate the up-going wave and down-going wave of the variable offset VSP.

A high-frequency circuit has a duplexer and a filter. The duplexer performs wave separation of send and received signals as input thereto. The filter filters the input send signal. When the send and received signals of the first modulation method are input, the send signal and the received signal of the first modulation method are wave-separated and output by the duplexer. When the received signal of the first modulation method is input, the send signal and the received signal of the first modulation method are wave-separated and output by the duplexer, and the send signal of the second modulation method is filtered by the filter.

The invention belongs to the field of seismic data migration imaging processing methods, and particularly relates to a diffraction wave imaging method based on anti-stationary phase filtering which can improve the imaging resolution of a heterogeneous diffraction target body. The scheme comprises the steps of carrying out conventional pre-stack Kirchhoff migration on a shot record after seismic data is acquired so as to acquire a full-wave-field imaging profile, extracting inclination angle information at each imaging point from a full-wave-field imaging result by using plane wave structure filtering technologies, constructing an anti-stationary phase filter by using the extracted inclination angle information, and using the constructed anti-stationary phase filter to act as a pre-stack Kirchhoff migration weight function so as to acquire a migration result only containing diffraction energy. According to the invention, the anti-stationary phase filter is introduced into conventional Kirchhoff migration, specular reflection meeting the Snell law is enabled to be effectively suppressed, and the diffraction energy is reserved, thereby improving the imaging resolution of the heterogeneous diffraction target body, being conducive to improving the interpretation precision of the seismic data, and being a diffraction wave separation and imaging technology which is practical and convenient to operate.

The invention belongs to the technical field of seismic wave information processing, and particularly relates to a longitudinal wave and transverse wave separation method and system. The longitudinal wave and transverse wave separation method comprises the steps that step a: a total vector displacement wave field U is simulated by utilizing an elastic wave equation numerical value in an isotropic medium; step b: all the components of the vector displacement wave field U are inputted, and a longitudinal wave separation equation vp=-alpha(Nabla*U) and a transverse wave separation equation vs=-beta(NablaxU) are obtained through calculation, wherein vp refers to a longitudinal wave speed wave field of a time-space domain, vs refers to a transverse wave speed wave field of the time-space domain, and alpha and beta respectively refer to propagation speed of longitudinal wave and transverse wave; and step c: the longitudinal wave field and the transverse wave field are respectively calculated by utilizing the longitudinal wave separation equation vp=-alpha(Nabla*U) and the transverse wave separation equation vs=-beta(NablaxU). According to the longitudinal wave and transverse wave separation method and system, the separated longitudinal wave field and the transverse wave field have clear physical meaning with no requirement for correction of amplitude and phase again so that error and interference caused by positive and negative transformation of the numerical value can be avoided.

The invention relates to a voltage control and phase shift compensation method for a three-phase grid connection current transformer under power grid failure conditions. The method includes the following steps that collected three-phase power grid voltages undergo Clarke transformation, and U<alphad> and U<betad> are obtained as feedforward quantities of a first set of power grid voltages for direct feedforward; Park transformation trapped wave separation is performed on the U<alphad> and the U<betad> to obtain the positive-sequence components and the negative-sequence components of the power grid voltages, the inherent delay angle theta<delay> is calculated according to low-pass filtering, AD sampling and a DSP, the components of the phase shift compensation quantities of the positive sequence and the negative sequence of the power grid voltages in a power grid positive and negative DQ coordinate system are respectively calculated, iPark transformation is performed on the positive and negative sequence phase shift compensation quantities through the angles + / -(omega*t+theta<delay>) which are compensated for, and the feedforward compensation quantities of a second set of power grid voltalges are obtained. The voltage control and phase shift compensation method for the three-phase grid connection current transformer under power grid failure conditions has the advantages that under power grid failure conditions, the feedforward control quantities of the power grid voltages can be responded to fast and accurately, and thus stable and reliable operation of the three-phase grid connection current transformer can be guaranteed, and high-voltage and low-voltage failure ride-through of a power grid is achieved.

The invention discloses an antenna layout structure for a concentric circle (or a coaxial circular table) uniform circular array vortex electromagnetic wave MIMO system. The structure is formed by nesting multiple uniform circular array antennas having the array element interval of lambda / 2 concentrically or coaxially. The invention discloses a multi-mode vortex electromagnetic wave MIMO signal separation method suitable for the antenna in the invention; namely, channel estimation is carried out by responses of No.0 array elements of arrays in various layers; then, MIMO solution is carried out according to a channel obtained by estimation and responses of layer-by-layer array elements of the antenna; a row vector corresponding to the layer is obtained from an MIMO solution matrix; mode separation of the row vector is carried out; independent modulation information carried in a multi-mode vortex signal propagated by the antenna corresponding to the layer can be obtained; and all layers of a receiving antenna are traversed, so that the MIMO gain and the mode multiplexing gain of the antenna disclosed by the invention can be obtained. Simultaneously, the invention discloses a vortex electromagnetic wave MIMO signal separation method and an implementation device based on a concentric circle (or a coaxial circular table) uniform circular array.

The invention provides a method for separating positive and negative sequence components on basis of OVPR under a non-ideal micro-grid condition. The method comprises the following steps of: transforming micro-grid voltage from a three-phase a / b / c coordinate system to a two-phase static <alpha> / <beta> coordinate system through Clark transform; and obtaining a positive sequence component and a negative sequence component of the voltage through a signal separation subsystem: carrying out subtraction on the micro-grid voltage transformed to the two-phase static <alpha> / <beta> coordinate system and sum of components obtained through separation, forming negative feedback through a fundamental wave positive sequence detection unit and a negative sequence detection uniform formed by a first-order vector resonant controller, and taking output of each unit as the positive sequence component and negative sequence component of the voltage. The method has the characteristics of being relatively rapid in response, free of instant symmetric component separation and simple to realize, and is capable of rapidly, correctly and directly realizing positive sequence, negative sequence and harmonic wave separation. Simulation results and analysis prove the correctness and effectiveness of the method.

The invention belongs to the technical field of wireless communication, and relates to a voltage-controlled oscillator (VCO) in a phase-locked loop, in particular to a Class-F voltage-controlled oscillator. The oscillator comprises a first resonant cavity, a cross coupling tube pair and a second resonant cavity, the first resonant cavity resonates at omega1, and the second resonant cavity resonates at 3omega1; that is to say, two separated inductors are adopted to form two resonant cavities, third harmonics and fundamental waves are separated, and a waveform similar to square waves is still formed at the drain electrode and the source electrode of the cross coupling tube. Moreover, the two resonant cavities replace a transformer structure, thereby avoiding repeated adjustment of the size of the transformer to ensure the performance requirements of the circuit, greatly simplifying the design process, and enabling the actual design to be more convenient. Meanwhile, a tail current sourceand a filter capacitor are removed, so that the circuit structure is simpler, and the problem of phase noise deterioration caused by the tail current source and the filter capacitor in the circuit iseffectively avoided.

A method for processing seismic data acquired using the same seismic survey setup over long periods of time includes acquiring sets of seismic data using the same seismic survey setup over multiple days, the sets being gathered as repeated seismic data. The method further includes estimating a time-variable wavelet corresponding to unwanted waves, and determining a propagation of the time-variable wavelet, which propagation is assumed to be constant in time, by solving an inverse problem using the repeated seismic data and the estimated time-variable wavelet. The method also includes extracting signal data by subtracting a convolution of the estimated time-variable wavelet and the propagation from the repeated seismic data.

The invention relates to a method for recording subsurface structure and directly imaging by utilizing micro-earthquake, micro-earthquake position and a wavelet are assumed to be known, reverse time migration is directly used, cross-correlation imaging conditions are adopted, a micro-earthquake event is served as a boundary condition for incident field reconstruction, a timeline-inversed micro-earthquake record is served as a boundary condition for scattered field reconstruction, and imaging is performed on a subsurface structure. According to the invention, the micro-earthquake event is served as the boundary condition for incident field reconstruction, the incident field precision of deep medium is effectively improved, and the deep medium imaging effect from the direct imaging method is effectively improved. Scattered micro-earthquake event can image without requirements of properties such as amount, density, distribution and the like of micro-earthquake; the micro-earthquake event is adopted to reconstruct the incident field, so that the incident field below a seismic source is more precise; a method for up and down wave separation and left and right wave separation is used for depressing high-frequency and low-frequency noises, solving wavelet shape is avoided, and plenty of calculation time is saved.

The invention discloses an imaging gather based diffracted wave separation imaging method. The method comprises the following steps of firstly, obtaining an imaging gather based diffracted wave separation method according to basic theoretical derivation and theoretical model research; secondly, in order for subsequent correct interpretive analysis, retaining a certain proportion of reflected waveenergy; and finally, improving the signal-to-noise ratio of a diffracted wave separation result by using an effective signal estimation method replacing wave filtration with inversion. As the calculation is necessarily carried out in different data domains, the calculation amount of directly solving the target function solution of a diffracted wave is too large; and an iterative way is adopted tosolve the solution in the method. By using such a method, not only is the calculation amount effectively reduced, but also, as the signal-to-noise ratio of an imaging gather is relatively higher, theseparation precision of a weak diffracted wave can be improved; and thus, the stability of the separation and the reliability of the separation result of a strong diffracted wave are enhanced.

The invention provides a diffracted wave separation method based on a kinematic wave field attribute, and belongs to the field of seismic exploration data processing. The method comprises (1) inputting a seismic data body, (2) performing automatic CMP superposition based on a CMP gather to obtain a parameter q and a ZO profile, (3) searching a parameter [beta] and a parameter R<N> based on the ZO profile, (4) calculating a parameter R<NIP> by utilizing the parameter q and the parameter [beta], and (5) performing wave field separation by utilizing the parameter R<N> and the parameter R<NIP> to obtain a diffracted superposition profile. A difference of a diffracted wave and a reflected wave in a kinematic characteristic is fully used, a filter formula of a separated diffracted wave is designed through the kinematic wave field attribute parameters obtained in a superposition process, and diffracted wave information is separated on the superposition profile.

The invention relates to the active filter current loop composite control technology field and especially relates to a composite-control active filter based on a high-compensated precision current loop and a control method thereof. The filter comprises an active-filter general control circuit connected to a sampling side power grid. The active-filter general control circuit comprises a harmonic wave separation module. An output terminal of the harmonic wave separation module is connected into a load side power grid successively through a current loop composite controller and a filtering module. An output terminal of the filtering module is connected to an input terminal of the current loop composite controller. By using the filter and the method of the invention, all the periodic errors contained in a stable closed loop can be effectively eliminated and stable state precision is increased.

The invention provides a wavelength-division-multiplexing-based ethernet passive optical network transmission system that is arranged on a circuit between a local-side optical line terminal and a client optical network unit and is used for transmitting a signal on a fiber. The system is composed of a first WDM-PON device, a first combiner / separator, a second combiner / separator, and a second WDM-PON device. To be specific, the first WDM-PON device is used for carrying out wavelength conversion on an optical signal; the first combiner / separator and the second combiner / separator are used for carrying out wave combination and wave separation on the signal; the second WDM-PON device is used for carrying out wavelength conversion on the optical signal. In addition, the invention also provides a wavelength-division-multiplexing-based ethernet passive optical network transmission method. According to the method, no modification on the original line and no laying of a new optical cable are required; and only a few of devices are added on the original line; and on the basis of wavelength conversion and wavelength division multiplexing of the ethernet passive optical network, transmission of a plurality of signals with different wavelengths is supported by one optical cable and thus the capacity of the user at the optical cable can be expanded by multiple times; and thus the heavy engineering load of reconstruction can be avoided under the circumstance that optical cable resources are insufficient.

The invention provides a diffraction wave separation method and a diffraction wave separation device. The method comprises the steps of acquiring frequency domain seismic data of an area to be processed; performing singular value decomposition on the frequency domain seismic data, and performing energy entropy computation on the decomposed singular value to acquire an energy entropy correspondingto each singular value; determining a diffraction wave singular value in the singular value based on the energy entropy, and determining a diffraction wave singular value vector corresponding to the diffraction wave singular value; and based on the diffraction wave singular value and the diffraction wav singular value vector, determining a target diffraction wave signal. According to the method provided by the invention, reflected waves can be effectively suppressed, meanwhile, the diffraction wave signal is protected, and finally the acquired target diffraction wave signal has good amplitudepreservation; the diffraction wave acquired after separation is good in effect, and the technical problems that the diffraction wave acquired via separation by using the existing diffraction wave separation method is seriously distorted, and the diffraction wave acquired after separation is poor in effect are relieved.

The invention provides a novel belt-shaped electron beam traveling-wave tube output structure. The output structure comprises a double rectangular waveguide coupling structure, an arc-shaped waveguide bend, a monoclinic medium matched load and a linear-type gradual-changing section, wherein the double rectangular waveguide coupling structure comprises an upper waveguide and a lower waveguide, the upper waveguide is an electromagnetic wave channel, the two ends of the electromagnetic wave channel are an electromagnetic wave output port and a matched load port respectively, the lower waveguide is an electron beam channel, the two ends of the electron beam channel are an electron beam output port and an electron beam input port respectively, and a rectangular coupling seam is arranged between the wave channel and the electron beam channel; the arc-shaped waveguide bend is connected with the electromagnetic wave output port; the monoclinic medium matched load is arranged at the matched load port; the linear-type gradual-changing section is connected with the electron beam output port. According to the structure, beam and wave separation can be effectively achieved, a wide electron beam channel, an isolation high-frequency interaction region and an electron collector region can be provided and a wide frequency band can have a good transmission coefficient.

The invention discloses a reflection wave separation method of a nonlinear wave based on the principle of waveform superposition. Through using a single fixed wave height meter to measure an incident wave with enough duration and a synthesis wave with the superposition of the incident wave and a reflection wave, the principle of waveform linear superposition is applied, the excellent stability and repeatability of the incident wave created by a wave tank are considered, the synthesis wave is directly subtracted from the incident wave, a reflection waveform can be obtained, and thus the purpose of separating the reflection wave is achieved. According to the method, only the single fixed measurement instrument is needed, and the method is suitable for linear and arbitrary high-order nonlinear regular wave problems. The measurement method is simple, the solution process is easy, and the separation efficiency of the reflection wave is improved.

The invention discloses a common scattering angle gather-based scattering wave separation method. The method includes the following steps that: data are shifted to a scattering angle domain through common scattering angular shift, so that a common scattering angle gather can be generated; and reflected waves and scattered waves are separated from each other according to the different response features of the reflected waves and scattered waves in the common scattering angle gather. With the common scattering angle gather-based scattering wave separation method of the invention adopted, the scattered waves can be well preserved under a premise that the reflected waves are separated out, and therefore, a capacity for recognizing the scattered waves can be improved, and a capacity for distinguish a fracture-cavity reservoir can be enhanced.

The invention discloses a two-step seismic diffracted wave field pre-stack separation process. The process comprises the following steps of 1, carrying out decompilation and preprocessing on field seismic data; 2, extracting a common offset gather on the basis of the preprocessed full-wave-field shot record; 3, separating the diffracted wave with the large inclination angle; 4, separating the diffracted waves with the small inclination angle; 5, carrying out complete diffracted wave synthesis; 6, extracting a diffracted wave shot gather or a common midpoint gather; 7, obtaining an imaging result of the diffracted wave; and 8, on the basis of the full-wave-field pre-stack time and depth migration imaging result, performing comprehensive explanation in combination with the imaging result ofthe diffracted wave. According to the method, calculation efficiency is improved and the storage space is saved without additionally increasing the data volume; moreover, noise interference such as false frequency is also avoided; meanwhile, precision of small-dip-angle diffracted wave separation under the condition of an inclined stratum or a bent event is improved; the separated diffracted wavefield information is more complete, and the diffracted wave imaging result is higher in amplitude preservation.