88 results about "Time inversion" patented technology

A time reversal process for determining a fault location in an electrical power network comprising multi-conductor lines, comprises measuring at an observation point located anywhere along one of the multi-conductor lines, for each of the conductors of the multi-conductor line, respectively a fault-originated electromagnetic transient signal; defining a set of guessed fault locations each having a different determined location in the electrical power network, and each of the guessed fault locations is attributed a same arbitrary fault impedance; defining a network model for the electrical power network, based on its topology and multi-conductor lines electrical parameters capable of reproducing in the network model the electromagnetic traveling waves; and computing for each conductor a time inversion of the measured fault-originated electromagnetic transients signal. The time reversal process method further comprises, as detailed herein, back-injecting a computed time inversion; calculating fault current signal energy; and identifying the fault location.

The invention relates to an electromagnetic-signal-time-inversion-based fault point positioning method for a transmission line. On the basis of an electromagnetic time inversion principle, a single observation point is set at any terminal in a power distribution network and a fault high-frequency transient signal within a limited period of time is measured and recorded; and time inverted sequenceprocessing is carried out on the measured signal, the processed signal is injected into a power distribution network simulation calculation model at an observation point, norm values at different guess positions in the power distribution network are calculated, and a fault position is determined by searching for a maximum peak value and a maximum energy root value. According to the method different form the traditional traveling wave determining method and impedance method, a power distribution network with a complex topological structure can be covered by one observation point without being affected by the fault impedance; and the excellent anti-noise performance is realized. The electromagnetic-signal-time-inversion-based fault point positioning method has the great practical value in fault positioning of the transmission line.

In some embodiments, apparatus and systems, as well as methods, may operate to acquire fluid signature data representing a plurality of nuclear magnetic resonance echo trains associated with fluids in a material, to simultaneously invert a plurality of relaxation time models to provide inverted results, and to determine fluid properties using the inverted results. The relaxation time models may be associated with the fluids using the fluid signature data after constraining ratios of T₁ relaxation times to T₂ relaxation times.

The invention discloses a laser methane concentration measuring method based on double-spectrum absorption line and waveform matching. A semiconductor laser performs wavelength linear scanning and covering on two specified absorption lines, laser passing through a gas to be measured is subjected to processing such as narrow-band band-pass filtering and high-speed acquisition by a receiving circuit and then subjected to waveform matching with a reference absorption line, various noises and interference removal and an actual absorption line retaining, and finally, real-time inversion of the concentration of the gas to be measured is carried out by adopting a double-spectrum absorption line concentration inversion algorithm. The laser methane concentration measuring method disclosed by the invention solves the contradiction widely existing in the conventional application of a laser absorption spectrum technology in gas concentration measurement that measurement range and minimum detection limit are difficult to consider, expands the concentration measurement range while ensuring the minimum detection limit of laser methane concentration measurement, solves the problem of concentration misinformation of a measuring system caused by optical and electrical interference, and ensures the measurement accuracy.

The invention relates to the field of mine water damage monitoring and water resource protection, and provides a mine water damage microseismic monitoring time-space cluster analysis method. The mine water damage microseismic monitoring time-space cluster analysis method comprises the following steps: extracting microseismic waveform signals; preprocessing the microseismic waveform signals; picking up microseismic signal beginning time; positioning microseismic events; with a floor crushed zone and a floor limestone mark layer of a stope as benchmarks, selecting a benchmark point Qi (xi, yi, zi), calculating the spatial distance between a microseismic event set and the benchmark point, and if a FORMULA is met, obtaining microseismic space cluster subsets; sorting the space cluster subsets in time sequence respectively to obtain microseismic event time-space cluster subsets. For the microseismic event groups which are randomly developed and mingled together, regularization of the microseismic events is achieved in the time domain and the space domain, that is, a microseismic time-space cluster method for describing the forming and changing processes of a water guiding passage is achieved, continuous real-time inversion of the water guiding passage, which is one of key factors causing mine water damage, in the time domain and the space domain is achieved, and thus the intelligent mine water damage prewarning capacity is greatly enhanced.

The invention provides an ultrasonic transcranial focusing method. The utrasonic transcranial focusing method comprises obtaining a skull image of a patient and reestablishing a three-dimensional digital model of a skull of the patient; guiding the three-dimensional digital model of the skull into a three-dimensional printer to obtain a corresponding skull entity model; performing time inversion on the skull entity model to obtain an ultrasonic transcranial focusing emission sequence. Accordingly, the entity model of the skull of the patient is accurately copied by a three-dimensional printing technology, the personalized ultrasonic transcranial focusing emission sequence is established outside the body of the patient by a time inversion method, and accordingly the accurate focusing is implemented and the accuracy, the treatment efficiency and the safety of the utrasonic deep brain stimulation can be effectively improved.

The invention discloses a target location method in specific environment and based on an active radio frequency identification device (RFID) and a system thereof, which adopt the mode of time inversion, are capable of conducting real-time high-accuracy location on an active RFID label on the premise that indoor environment is not modified, conduct simulation of the communication process of electromagnetic wave after the time inversion in a simulation environment, determine the position of a target to be located by reading peak value of energy of an electromagnetic field, and overcome the shortcoming that the traditional location accuracy relies on complexity of environment. The time inversion process is not finished on the target to be located, so that complexity and cost of the target to be located are reduced. A real transmitter is not required, so that complexity and cost of a signal processing mechanism are reduced. The simulation environment built in the signal processing mechanism corresponds to the real specific environment, and the multi-diameter and multi-scattering conditions can all be fully utilized in the time inversion process. Compared with the prior location mode, the method and the system reduce arrangement number of fixed antenna and reduce system cost.

The invention relates to a precoding technique in a massive MIMO network based on time inversion, specifically relates to the fusion and improvement of the time inversion technique and the precoding technique in the massive MIMO network, and achieves the purpose of interference inhibition. The channel optimization of the technique is performed on the basis of the time inversion technique, and thetechnique achieves the energy gathering through the spatiotemporal focusing of the time inversion technique. The improvement is achieved on the basis of the zero-forcing precoding technique, and the technique reduces the inter-user interference and co-channel interference in the massive MIMO network through the zero-forcing precoding technique in a multi-path environment, thereby achieving the interference inhibition. A receiving end antenna can obtain the channel state information of a multi-path channel at a base station antenna end through the channel detection, and the up-sampling is performed on the base station antenna so as to reduce the signal transmission rate. The inter-user interference and co-channel interference are reduced under the condition of the multi-path channel throughthe zero-forcing precoding technique, so the technique provided by the invention can enable the mean bit error rate to be reduced, and remarkably improves the SINR (Signal to Interference plus NoiseRatio) and the achievable rate of the massive MIMO system.

The present invention discloses a magnetotelluric synchronizing detection and real-time inversion method and system. The system comprises a detection inversion host (M) with a wireless networking function and N<2>-1 detection inversion extensions (Si) with wireless communication functions, wherein the distance between each two detection inversion extensions is D, i=1, 2, ..., N<2>-1, and N is an odd number. The detection inversion host is used for collection of magnetic field signals and electric field signals of measurement points, wireless networking and cooperation, synchronizing detectionand real-time inversion control of the detection inversion extensions in a detection area, and the detection inversion extensions are used for synchronizing collection of electric field signals of themeasurement points and real-time inversion of detection data of the measurement points under the cooperative control of the detection inversion host. The detection inversion host and the detection inversion extensions synchronously perform detection and inversion in real time to avoid that a time-space factor influences improvement of observation data quality while improving the work efficiency,and therefore the magnetotelluric synchronizing detection and real-time inversion method and system can be widely used in fields of underground mineral resource detection, construction detection of the earth's crust and the upper mantle and the like.

The present invention relates to the technical field of wireless communications, in particular to a spatial multiplexing TR equalizer design based on a SIMO-UWB system, which comprises that a transmitting end transmits a detected signal; a receiving end estimates a channel type according to a channel state; according to different channel types, a channel transmission model is established, and channel parameters are estimated; the estimated channel parameters are fed back to the transmitting end and a time inversion mirror by the receiving end; the equalizer is designed by using the space-timefocusing characteristic of the time inversion technology; power control is carried out on the equalizer, and TR pre-filter cascade is used for the SIMO-UWB system. According to the equalizer design inthe invention, multi-code stream interference and inter-symbol interference in the SIMO-UWB system are reduced under the premise of ensuring normal communication of the system, the system complexityis reduced, and the performance of the system is greatly improved.

The invention discloses a method used signal focalizing to monitor engineering structure connecting failure. It includes the following steps: collecting structure response signal; time inversion processing; sensing signal focalizing; characteristic parameter extracting and structure health identifying. It can increase sensitivity for the structure connecting failure monitoring method based on acoustic excitation, be good for the practicality of the technique, and actualized method.

A conductivity image reconstructing method for magneto-thermoacoustic coupled tomography includes: acquiring a thermoacoustic source distribution of a conductive object by means of time inversion according to an electromagnetic ultrasonic signal received, and performing reconstruction according to the thermoacoustic source distribution to obtain a conductivity distribution of the conductive object. Specially, the method includes: acquiring a thermoacoustic source on a certain level by means of time inversion, acquiring a thermoacoustic source of the conductive object by means of interpolation, performing calculation by means of Biot-Savart's law according to excitation current to obtain a spatial component A1 of primary magnetic vector potential, subjecting the conductive object to spatial discretization, giving an initial value [Sigma]<0> of conductivity, according to the theorem of current continuity, solving a spatial component [Phi] <1> of scalar potential with the initial value [Sigma]<0> and the spatial component A1, substituting the spatial component [Phi]<1> of the scalar potential to a relation which the thermoacoustic source and conductivity meet so as to obtain updated conductivity [Sigma]<1>, replacing the initial value [Sigma]<0> with the updated conductivity [Sigma]<1>, repeating the process above, and stopping iteration until a relative error of the conductivity meets an equation: Sigma=||([Sigma]1-[Sigma]0)/[Sigma]0||2<=Sigma0.

The invention discloses a multi-antenna diversity receiving method and device based on time inversion. The method comprises the following steps of: firstly, carrying out down-conversion treatment on radio frequency signals received by antennas respectively to obtain multiple unrelated compound baseband signals; next, carrying out channel evaluation respectively according to the obtained compound baseband signals to obtain independent transmission channel parameters of receiving antennas; then, working out time inversion conjugate formulae of channels according to the evaluated channel parameters; and then, carrying out convolution operation on the compound baseband signals received by the antennas and the time inversion conjugate formulae of corresponding transmission channels respectively; finally, processing the convolution result by an equal gain combination method to obtain a final multi-antenna diversity result. According to the method and device disclosed by the invention, the signal-to-noise ratio of the received signal can be increased, combination and balance strategies are simplified, and the performance of the wireless communication system is improved.

The invention provides a real-time inversion analysis method of concrete dam block surface heat emission coefficient. The real-time inversion analysis method monitors climatic conditions around a damblock, dam block surface temperature and a temperature inside the dam block in real time; temperature variation parameters inside the dam body are calculated by a direct solution method, by combiningwith shape parameters and material thermodynamic and mechanical parameters of the dam body, an interpolation and iteration method is used for inversely analyzing and determining the dam block surfaceheat emission coefficient based on a finite element method, temperature control and cracking prevention can be carried out better, and the accuracy and calculation efficiency are higher.

The invention relates to a method for performing focusing shaping control on a distorted femtosecond laser pulse. The method is characterized in that an optical inverse diffusion algorithm is writtenaccording to a time inversion principle; a phase shift holographic algorithm is written according to a holographic interference principle; light beams output from a laser 1 are incident on a beam splitter 2 and are divided into two parts, one part entering a sample light path 3.1-8 and the other part entering a reference light path 3.2-8. The light beams in the reference light path 3.2-8 are reflected onto an isosceles prism 10 by a second mirror 3.2 and a third mirror 3.3, the light beams are reflected to a fourth mirror 3.4 by the isosceles prism 10, and the light beams are reflected by thefourth mirror 3.4 and then input to a two-dimensional spectrometer 8. According to the method in the invention, the spatial freedom of the wave-front in a spatial light modulator is controlled by running the optical inverse diffusion algorithm through a computer, thereby realizing simultaneous focusing shaping control on the spatial distortion and time distortion of the femtosecond laser pulse.

The invention discloses an autonomous dynamic wireless power receiving device and method based on time inversion, and belongs to the technical field of wireless power transmission. According to the invention, the device achieves the uplink and downlink isolation of an energy transmission request signal and a time inversion return signal by using a transceiving isolation module, and achieves the transmission of the energy transmission request signal and the receiving of a time inversion return signal are transmitted through the same port of the same antenna, thereby eliminating the channel difference between the transmission process of the energy transmission request signal and the return process of the time inversion signal, and improving the wireless energy transmission efficiency. According to the invention, the device can control the starting stage, the stable transmission stage and the terminating stage of wireless electric energy transmission and the re-transmission of electric energy due to the movement of the receiving device and the change of transmission channel parameters, and achieves the purpose that a mobile receiving terminal autonomously completes the whole process of inversion of wireless electric energy receiving. According to the invention, the device can achieve the high-efficiency, movable and manual intervention-free autonomous time inversion wireless electric energy receiving.

The invention discloses a same-time same-frequency duplex electromagnetic communication method based on time reversal, relating to the technical field of microwave. The time-space focusing and super-resolution focusing properties of time reversal electromagnetic wave are used, only through the separation of a sub wavelength interval of the receiving and transmitting ends of two communication parties, the effective inhibition of self interference signals of the receiving and transmitting ends of a same communication party can be realized. At the same time, since the time inversion technology is used, even the interval between antenna units is in a sub wavelength state, the corresponding receiving and transmitting channels are still independent, thus according to the method provided by the invention, the communication module complexity can be reduced, the communication rate can be increased, and the system capacity is increased.

The invention provides a monitoring and early warning system for a comprehensive pipe gallery. An intelligent sensing original part and monitoring equipment are arranged in the comprehensive pipe gallery. The monitoring and early warning system for the comprehensive pipe gallery comprises a data and information module, a numerical value calculating module, an artificial intelligence analyzing module and a monitoring and early warning module, wherein the data and information module is used for collecting and sorting data acquired by the intelligent sensing original part and the monitoring equipment; the numerical value calculating module is used for carrying out real-time inversion analysis on the data; the artificial intelligence analysis module is used for intelligently analyzing characteristics and rules of the data acquired by the intelligent sensing original part and the monitoring equipment; and the monitoring and early warning module is used for carrying out safety analysis on the comprehensive pipe gallery, establishing a pipe gallery safety evaluation model, and providing safety evaluation and health diagnosis reports. According to the monitoring and early warning system for the comprehensive pipe gallery, the artificial intelligence analysis module is utilized to carry out intelligent analysis, the numerical value calculating module is used to carry out real-time inversion analysis on the data, and thus, real-time diagnosis and early warning on the health state of the comprehensive pipe gallery are realized.

The invention relates to a microseismic damage reconstruction based mining-induced stress evaluation method, and is suitable for use in the field of microseismic monitoring in the field of mine safety. The method specifically comprises the steps of carrying out grid partition on an evaluation area; calculating cumulative deformation energy Epsilon Ei and a microseismic event number or a coal rockloading time Delta ti of each grid node by adoption of an accumulation method; finding out a maximum cumulative deformation energy value max {Epsilon Ei} of the evaluation area and calculating averagecumulative deformation energy Epsilon F; and obtaining mining-induced stress distribution on the basis of calculating damage parameter D distribution. The method has obvious physical and mechanical significance, has involved parameters which are clear and strong in universality and operability, is suitable for programming, has good application feasibility, and can realize approximate real-time inversion of mining-induced stress in coal seam mining processes.

The invention discloses a method for generating a non-diffraction Bessel wave based on time inversion and relates to the field of electromagnetic beamforming. The method comprises a step 1 of selecting a cross section as an initial wave emission surface according to the electric field and magnetic field distribution of the Bessel wave, obtaining the initial wave emission surface field distributionand calculating the maximum non-diffraction distance of the initial wave according to the field distribution; a step 2 of emitting the initial wave to propagate the initial wave in a free space, andintercepting an electric field at the maximum non-diffraction distance to obtain electric field values at various positions of the initial wave emission surface; and a step 3 of performing, after theelectric field value of the initial wave emission surface is discretized, a time inversion operation to obtain an inversion Bessel wave, emitting the inversion Bessel wave to propagate the inversion Bessel wave in the same free space and to generate a non-diffraction Bessel wave. The method solves the problem that the existing non-diffraction distance of the Bessel wave generated in the microwavefrequency band is short, and achieves an effect of greatly increasing the non-diffraction distance of the Bessel wave field.

The invention discloses a time-inversion super-resolution pipeline leakage monitoring method. Compared with the prior art, the invention has the advantages as follows: in allusion to the defect that ametamaterial component is required to be used near a signal source for achieving super-resolution imaging positioning in a conventional scheme, a time-inversion super-resolution time domain adjustment function is provided and designed, and through adjustment of the function, the resolution can be increased and a resolution diffraction limit can be broken through. By the time-inversion super-resolution pipeline leakage monitoring method, super-resolution is achieved by an algorithm and the metamaterial component is not required to be used, so that the time-inversion super-resolution pipeline leakage monitoring method has higher practicality and lower cost than the conventional time-reversion super-resolution imaging positioning scheme. Therefore, by using the novel technology, low-cost andsuperhigh-resolution leakage monitoring of a long-distance gas pipeline can be achieved.