30 results about "Ionospheric electron density" patented technology

The invention discloses an integrated real-time correction system for atmosphere convection layer and ionized layer radio wave refraction errors, which comprises a microwave radiometer, a single-station GPS (Global Positioning System) and an integrated real-time correction unit, wherein the microwave radiometer is used for detecting a convection layer refractivity profile; the single-station GPS is used for detecting an ionized layer electron density profile in real time; and the integrated real-time correction unit is used for calculating radio wave refraction error corrections in real time by adopting a ray tracing method based on the convection layer refractivity profile, the ionized layer electron density profile and the apparent distance and the apparent elevation angle parameter of a detection target, wherein the radio wave refraction error corrections comprise a distance error correction, an elevation angle error correction and a speed error correction. The integrated real-time correction device for atmosphere convection layer and ionized layer radio wave refraction errors overcomes the defect that the parameters of a convection layer and an ionized layer cannot be simultaneously detected by adopting the traditional method, realizes the real-time correction of the radio wave refraction errors of the convection layer and the ionized layer, has the advantages of high accuracy, good real-time performance, unattended operation, strong mobility, low cost, simplicity in operation and the like, and provides a technical support for improving the accuracy of systems for aerial survey, deep-space survey, ballistic trajectory measurement and the like in China.

The invention discloses a multi-source data fusion-based three-dimensional ionosphere chromatographic method, utilizes GNSS observation data, occultation observation data on low orbit satellites, Jason-1 and Jason-2 seasat altimetry data and ionosphere altimeter data for the first time, and develops research on ionosphere electron density tomography. An inversion result is compared with observation data of an incoherent scattering radar, and a result verifies effectiveness and reliability of the three-dimensional ionosphere chromatographic method provided by the invention in fusing multi-source data to perform inversion of ionosphere electron density and superiority of the method to use of GPS observation data alone to perform inversion.

The invention discloses a detection method for the electron density of an ionization layer based on radar echoes. The method is realized by the following steps that (1) original data is collected and stored; (2) non-coherent scattering echoes are extracted from the ionization layer; and (3) the electron density of the ionization layer is calculated. The disclosed detection method has great significance in radar wave environment adaptation and space environment monitoring and early-warning domestically; and compared with a present special-purposed electron density detection method for the ionization layer, the method of the invention is simple and economic. The method of the invention is also high in compatibility and transplantability, and is suitable for most space monitoring radars, and the radars need only to provide signal interfaces of original echo signals, emission pulse signals, main pulse signals and sampling clock and the like.

The invention relates to an ionized layer chromatography method and system based on multi-constellation GNSSs. The ionized layer chromatography method comprises the steps that multiple satellite navigation systems are adopted to carry out the ionized layer chromatography, firstly, an object region range is determined, observation data corresponding to all the satellite navigation systems within the object region range are selected; then total electron content corresponding to all the satellite navigation systems is calculated, and the relation between the total electron content of the satellite navigation systems and desired ionized layer electron density is obtained; and finally, the relation between the total electron content of the satellite navigation systems and the desired ionized layer electron density is subjected to inversion calculation, and the ionized layer electron density of the object region range is obtained by the calculation. The ionized layer chromatography operationis carried out through multiple different satellite navigation systems, and compared with an existing operation which is carried out only through one kind of satellite navigation systems, the accuracy of the ionized layer electron density obtained by the inversion is improved greatly, and the reliability of the ionized layer chromatography method is improved equally.

The invention discloses an ionized layer chromatography technology and an ionized layer delay correction method based on multi-scale subdivision. A three-dimensional space of an area ionized layer is subdivided according to different 'pixel' scales to obtain a plurality of different single-scale ionized layer chromatography models, unknown variables of the models are uniformly solved and weighted according to different weight factors to obtain solutions of a multi-scale chromatography model, and electron density distribution of the area ionized layer is reconstructed to obtain delay of the area ionized layer. The space activity rule of the reconstructed ionized layer is high in fitting degree, high in timeliness and convenient to use. According to the obtained area ionized layer, the delay quantity solution result is high in accuracy, so that the application range of CORS measurement results is enlarged. It is proved through a lot of project case application result analysis that the electron density distribution of the area ionized layer reconstructed through the method is more smooth and reasonable compared with a traditional single-scale ionized layer chromatography model, and ionized layer delay correction accuracy is improved by 30% on average.

The invention discloses a CORS-based regional ionospheric electron density three-dimensional real-time monitoring system and method. The real-time monitoring system comprises a CORS data real-time acquisition module, a Real-Time Service (RTS) real-time acquisition module, a real-time precise ephemeris generation module, a real-time data management module, an ionospheric data processing module, a display module and a product service module. The CORS-based regional ionospheric electron density three-dimensional real-time monitoring system and method has the significant effects that real-time three-dimensional ionospheric electron density products based on global satellite navigation systems such as GPS, GLONASS or Beidou system can be stably provided in real time through a GNSS reference station network and the ionospheric data processing module, and real-time monitoring of a regional ionosphere is realized; and the realization cost is low, ionospheric products with real-time and high spatial-temporal resolution are provided without increasing the construction cost, and the CORS-based regional ionospheric electron density three-dimensional real-time monitoring system and method is apowerful supplement to traditional ionospheric monitoring methods.

The invention discloses a ligand molecular compound with diversified steric configuration and Pi electron density. The compound is a ferrocenyl amido compound, and is prepared by a special three-stepreaction according to the certain sequence through changing the structure of the different reaction raw materials. The invention further discloses an application of the compound for synthesizing goldnanoparticles with large particle size. Proved by an experiment, the ligand molecular compound is used for synthesizing the gold nanoparticles with the large particle size through a one-step reaction.Compared with a conventional method of more than ten reaction steps, the obvious improvement and optimization are realized. In order to further research the action between nano materials with the different surface properties and a biological system, a model and a method are provided for the ligand molecular compound. The ligand molecular compound has the important reference significance to research the relation between the material surface properties and the biological effect and the relation formed with multiple diseases.

The invention relates to a method and device for detecting the ionosphere total electron density. In a to-be-tested area, two dual-frequency GPS receiver antenna with a spacing of about 10 meters are put up to receive GPS satellite signals, and the GPS satellite signals are transmitted into two dual-frequency GPS receivers by a coaxial cable wire, satellite signals are processed by the dual-frequency GPS receiver, the received data is saved through a communications cable wire in a computer, data for one day is taken, and processing is conducted on the data using a software program. A polynomial model is established to calculate the delays of the dual-frequency GPS receiver and the satellite hardware, skewed total electron density is obtained after the removal of the delays of the dual-frequency GPS receiver and the satellite hardware, the total electron density of two skewed dual-frequency GPS receivers is integrated, through a projection function, is converted to a vertical total electron density. By the adoption of the 10 meter rank short base line based on the foundation GPS double-station layout mode, the ionosphere total electron density is detected, the accuracy is high, and data storage, management and device maintenance are easy.

The invention relates to an ionosphere chromatography method and device, and the method comprises the steps: building a new combination quantity according to the combination quantity and intercept value in an MART algorithm, determining an iterative equation of the electron density of an ionosphere according to the new combination quantity, and carrying out the chromatography inversion of the ionosphere according to the iterative equation, so as to obtain the electron density. According to the invention, the intercept value and the electron content in the pixel are used as the combination quantity to construct a new combination quantity, and the electron content and the intercept value are comprehensively considered, so that the inversion precision is effectively improved, and the iteration result is more accurate.

The invention discloses a satellite-based ionospheric inversion method based on an electromagnetic satellite. The method comprises the steps: carrying out data extraction and separation of observationdata to obtain GPS obscuration observation data and BD obscuration observation data; performing quality detection and gross error elimination on the GPS obscuration observation data and the BD obscuration observation data; according to the processed GPS obscuration observation data and BD obscuration observation data, carrying out data interpolation and time synchronization calculation to obtainGPS obscuration orbits or BD obscuration orbits corresponding to all obscuration moments and LEO orbit data; carrying out TEC calculation on a signal propagation path; obtaining a corrected TEC'; inverting the ionospheric electron density according to the corrected TEC'; and discretizing the ionospheric electron density obtained by inversion to obtain an electron density profile. According to theinvention, the GPS ionospheric occultation event and the Beidou ionospheric occultation event can be detected at the same time, and the detected ionospheric occultation event can cover the world.

The invention discloses an occultation atmospheric detection system based on a tail sub-level cluster, and the system is characterized in that a GNSS occultation detection load is loaded on an orbit-remaining tail sub-level cluster provided with an orbit-remaining platform, and the orbit-remaining tail sub-level cluster comprises a plurality of orbit-remaining tail sub-levels on a sun-synchronous orbit task and an inclined orbit task; the orbit remaining tail sub-levels adjust the attitude through an orbit remaining platform, receive a direct signal of a GNSS navigational star and an ascending occultation signal and a descending occultation signal of GNSS occultation through a GNSS occultation detection load, and analyze parameter data including ionosphere electron density, atmospheric refractive index and temperature and humidity profile to realize atmospheric detection. The orbit remaining tail sub-level under high-density launch of a carrier rocket is fully utilized to carry out adaptive modification, the orbit remaining tail sub-level and an existing GNSS occultation detection satellite constellation form a giant hybrid detection network, and the temporal-spatial resolution and the detection precision of GNSS occultation atmosphere detection can be effectively improved.

The invention discloses an ionized layer irregular shape body diffraction imaging method based on p band satellite borne synthetic aperture radar (SAR), and relates to a radar imaging technique. The steps are as follows. (1). An ionized layer signal is separated from a time domain echo signal of satellite borne p band SAR. (2). SAR diffraction imaging is used to confirm a rough range and a location of a target. (3). The relationship between radar echo and ionized layer electron density is built according to an electric-field integral equation. (4). Diffraction imaging method is used to image an irregular shape body. The ionized layer irregular shape body diffraction imaging method based on p band satellite borne SAR is simple and easy, and solves a problem of a big calculated amount and a big storage volume in an ionized layer irregular shape body diffraction imaging method.

The invention discloses an ionosphere detection method and system; the method comprises the following steps: using a USRP to emit electromagnetic waves of a set frequency and to receive electromagnetic wave reflected by the ionosphere, and recording emitted and received electromagnetic wave information; allowing the USRP to communicate with a computer through a gigabit internet access, and the computer uses the emitted and received electromagnetic wave information to calculate the ionosphere height, ionosphere electron density and ionosphere electron radial speed under the set electromagnetic wave emission frequency; changing the USRP emitted electromagnetic wave frequency, obtaining the ionosphere heights, ionosphere electron densities and ionosphere electron radial speeds under different electromagnetic wave emission frequencies, and drawing an ionosphere distribution map. The advantages are that the USRP communicates with the computer through the gigabit internet access, thus emitting and receiving electromagnetic waves, and primarily processing the signals; the computer can calculate complex signal processes and related detection targets, and the USRP and the programmed computer can detect the ionosphere with low cost; the ionosphere detection method is flexible, convenient, high in opening degrees, and easy to maintain.

The invention discloses an ACMART method for GNSS ionosphere chromatography. The method comprises the following steps: S1, building a new iterative model through the multiplication of the intercept ofa ray passing through a grid and the electron density of the grid, and redistributing an error between a measured value and an inversion value of the total electron content of an ionosphere in gridswith different electron densities; S2, developing a self-adaptive iteration factor; and S3, carrying out smooth constraint according to the continuity and smoothness distribution characteristics of the electron density of the ionized layer between the adjacent grids. The method has important application value in GNSS navigation positioning precision improvement and disaster reduction and prevention capability of the space environment.

The invention belongs to the field of signal and information processing, and specifically relates to an ionospheric electron density inversion method, system, and device based on the CLEAN algorithm, aiming at solving the large amount of calculation of incoherent scattered plasma spectral lines and the insufficient accuracy of electron density profile inversion The problem. The method of this system includes: obtaining the IQ digital signal; extracting and deleting the signal part collected during the pulse transmission in the IQ digital signal, and constructing a two-dimensional matrix; decoding and calculating the signal power spectrum of each range gate height through the frequency domain FFT algorithm; iteratively obtaining each distance Accumulate the power spectrum data of the gate height, and denoise through the system frequency response function; deconvolute the denoised power spectrum data based on the CLEAN algorithm; obtain the plasma spectral line of the entire height profile by the spline interpolation method, and The ionospheric electron density profile was obtained by fitting the Langmuir dispersion relation. The invention improves the real-time calculation of plasma spectral lines and the precision of electronic density profile inversion.

The invention discloses an integrated real-time correction system for atmosphere convection layer and ionized layer radio wave refraction errors, which comprises a microwave radiometer, a single-station GPS (Global Positioning System) and an integrated real-time correction unit, wherein the microwave radiometer is used for detecting a convection layer refractivity profile; the single-station GPS is used for detecting an ionized layer electron density profile in real time; and the integrated real-time correction unit is used for calculating radio wave refraction error corrections in real time by adopting a ray tracing method based on the convection layer refractivity profile, the ionized layer electron density profile and the apparent distance and the apparent elevation angle parameter of a detection target, wherein the radio wave refraction error corrections comprise a distance error correction, an elevation angle error correction and a speed error correction. The integrated real-time correction device for atmosphere convection layer and ionized layer radio wave refraction errors overcomes the defect that the parameters of a convection layer and an ionized layer cannot be simultaneously detected by adopting the traditional method, realizes the real-time correction of the radio wave refraction errors of the convection layer and the ionized layer, has the advantages of high accuracy, good real-time performance, unattended operation, strong mobility, low cost, simplicity in operation and the like, and provides a technical support for improving the accuracy of systems for aerial survey, deep-space survey, ballistic trajectory measurement and the like in China.

The invention relates to a global ionospheric total electron content multi-layer analysis method based on low earth orbit satellites, and the method comprises the steps: calculating the ionospheric total electron content through the satellite navigation double-frequency observation quantity of a satellite-borne receiver through the global low earth orbit satellites distributed at different heightgroups; achieving multi-layer analysis of global ionospheric total electron content spatial distribution in combination with an output product of a ground satellite navigation observation network, andthen correcting a multi-layer analysis result by utilizing a vertical distribution profile of medium-low-layer ionospheric electron density obtained by an occultation receiver. Compared with a traditional global ionospheric total electron content distribution calculation method, the method has the advantages that distribution characteristics of ionospheric electron densities at different heightscan be effectively extracted, the space-time precision of two-dimensional ionospheric total electron content distribution is improved, and a good technical support is provided for global three-dimensional space distribution of comprehensive cognition of the ionospheric total electron content.

The invention relates to an ionosphere TEC combined prediction method combined with an ionosphere chromatography technology. The method comprises the following steps: calculating the ionized layer electron density of a prediction area by using an ionized layer chromatography algorithm, calculating the total electron content VTEC in the vertical direction, and calculating the VTEC of the prediction area by using an IRI model; constructing a combined prediction model based on the two VTECs, and achieving the model training, model prediction, and model test result and model precision analysis. The invention has the beneficial effects that the LSTM model is used for predicting the chromatography vertical total electron content VTEC, the BP neural network is further used for conducting nonlinear fitting on prediction results of the LSTM model and the IRI model, and therefore the defects of a single prediction model are overcome, and time sequence prediction of the ionospheric vertical total electron content VTEC is better achieved.

The invention discloses an ionospheric tomography technology based on multi-scale subdivision and an ionospheric delay correction method. The three-dimensional space of the regional ionosphere is subdivided according to different "pixel" scales, thereby obtaining multiple different The single-scale ionospheric tomography model, the unknown variables of these models are uniformly solved, and according to different weight factors, finally weighted to obtain the solution of the multi-scale tomography model, the ionospheric electron density distribution in the region is reconstructed, and the regional ionospheric electron density distribution is obtained. Ionospheric delay. The ionospheric space activity law reconstructed by the invention has a high degree of fitting, strong timeliness, and is convenient to use; the regional ionospheric delay amount calculation result obtained according to the invention has high accuracy, which expands the application range of CORS measurement results. After analyzing the application results of a large number of engineering examples, the ionospheric electron density distribution reconstructed by the invention is smoother and more reasonable than the traditional single-scale ionospheric tomography model, and the accuracy of ionospheric delay correction is increased by 30% on average.

The invention discloses a method for predicting change of very-low-frequency electric wave field intensity along with time in a high-precision mode. The method comprises the following steps that 1, ionosphere electron density Ne changing along with height is obtained in combination with an IRI model; step 2, obtaining an ionosphere reference height H and a gradient coefficient beta of the index model at each moment through the ionosphere electron density Ne; 3, deducing an electric field component Er of the very-low-frequency electromagnetic wave; 4, solving the complex dielectric constant of the ionized layer through the reference height H and the gradient coefficient beta of the ionized layer of the index model at each moment, and obtaining the reflection coefficient and the surface impedance of the ionized layer; and step 5, through the surface impedance and the electric field component Er, obtaining the field intensity of the very-low-frequency electric wave corresponding to different time periods, and accurately predicting the change condition of the field intensity of the very-low-frequency electric wave along with time. According to the method, index model parameters are inversed based on an IRI model, ionosphere reference height and gradient coefficients changing along with time are obtained, and on the basis of a waveguide mode theory, propagation characteristics of very-low-frequency electric wave field intensity changing along with time are analyzed and predicted.

The invention provides an edge-enhanced ionosphere chromatography method. The method comprises the following steps: step 1), jointly resolving a measured ionosphere TEC by using a GPS code observation value and a carrier phase observation value; step 2), establishing a virtual reference station, and calculating a virtual TEC value through triangular linear interpolation; 3) uniformly dividing the to-be-inverted region into grids according to the longitude, latitude and height directions, calculating the intercept of all observation signals in each grid, and arranging the observation signals according to the sequence of the grids and the observation times to form an observation matrix A; 4), adopting an IDW interpolation method as a horizontal constraint, and enabling the grids through which no signal rays pass to participate in chromatography iteration; and 5), constructing an edge function, and solving ionosphere electron density distribution through an ART iterative algorithm. According to the method, the situation of marginal area observation signal scarcity in actual inversion is fully considered, correction weighting is carried out on the ART algorithm to limit correction on the marginal area, and over-fitting is prevented.

The present invention provides a GNSS occultation ionospheric residual correction method and system based on ionospheric electron density. The method includes: preprocessing GNSS occultation raw observation data and ionospheric vTEC maps data, and obtaining GNSS occultation geometric data and ionospheric data; based on GNSS occultation geometric data, ionospheric data and three-dimensional NeUoG ionospheric model, calculate the electron density profile of the ionospheric puncture point on the "incoming ray" and "outgoing ray" sides; based on GNSS occultation geometric data and the electron density profile to calculate the curved angle ionospheric residual profile. The GNSS occultation ionospheric residual correction method and system of the present invention can be used in the inversion of atmospheric parameters of a single GNSS occultation event to weaken the influence of ionospheric residuals, thereby obtaining a higher-precision GNSS occultation bending angle profile, Efficient and reliable.

The invention discloses an ionospheric occultation inversion method based on double-parameter mixed regularization, which is characterized in that it includes: (1) preprocessing satellite observation data to obtain observation values; (2) using GPS precise ephemeris Interpolate the satellite coordinates at the desired moment; (3) utilize GPS dual-frequency observations to calculate the TEC on the propagation path; (4) double-parameter hybrid regularization method to invert ionospheric electron density; the present invention improves the calculation of ionospheric electron density. The accuracy of the density can greatly reduce the influence of measurement errors, thereby improving the inversion accuracy of the electron density.

The invention belongs to the field of signal and information processing, particularly relates to an ionized layer electron density inversion method, system and device based on a CLEAN algorithm, and aims to solve the problems of large incoherent scattering plasma spectral line calculation amount and insufficient electron density profile inversion precision. The method of the system comprises the following steps: acquiring an IQ digital signal; extracting and deleting a signal part acquired during pulse emission in the IQ digital signal, and constructing a two-dimensional matrix; decoding and calculating a signal power spectrum of each distance gate height through a frequency domain FFT algorithm; iteratively acquiring power spectrum data of each distance gate height for accumulation, and denoising through a system frequency response function; performing deconvolution on the denoised power spectrum data based on a CLEAN algorithm; obtaining a plasma spectral line of the whole height profile through a spline interpolation method, and obtaining an ionized layer electron density profile through Langmuir dispersion relation fitting. According to the invention, the real-time performanceof plasma spectral line calculation and the precision of electron density profile inversion are improved.

The invention discloses a method, a device and a system for radio wave refraction correction. The method comprises the following steps of: based on historical meteorological sounding data and ground temperature-humidity-pressure data, obtaining troposphere refractive index profile in real time; based on a GNSS (Global Navigation Satellite System) signal acquired by a ground-based singular GNSS receiver, obtaining an ionized layer vertical total electron content measured value in real time, and based on the ionized layer vertical total electron content measured value, inversing the ionized layer electron density profile through a genetic non-linear optimization algorithm; calculating the radio wave environment refraction error through a ray tracing method according to the troposphere refractive index profile and the ionized layer electron density profile; and correcting the target detection data. The method, the device and the system can improve the radio wave environment sensory capability in engineering, accurately provide the radio wave environment refraction error and effectively improve the detection precision of a target.

The invention discloses a GNSS ionosphere delayed three-dimensional modeling method suitable for a global area. The GNSS ionosphere delayed three-dimensional modeling method comprises the steps of acquiring an empirical orthogonal function which is used for representing vertical distribution of ionosphere electrons, establishing an ionosphere model based on a spheric harmonics function and the empirical orthogonal function by means of an ionosphere TEC observation amount which has been accurately estimated, and constructing an accurate three-dimensional modeling method which is suitable for ionosphere delay of the global area. Compared with an existing method, the GNSS ionosphere delayed three-dimensional modeling method is advantageous in that the empirical orthogonal function is used for representing vertical density distribution of the ionosphere electrons; not only is limitation of an ionosphere delay two-dimensional model overcome, but also change information of ionosphere large-scale structure (such as equator abnormity, midlatitude trough and different ionosphere disturbance) can be effectively monitored; and furthermore the GNSS ionosphere delayed three-dimensional modeling method has important scientific meaning and application value in monitoring and researching different scale inhomogeneities, ionosphere environment, ionosphere temporal and spatial variation and monitoring the ionosphere in a global range.

The invention discloses an ionosphere modeling method based on ionosphere warp change characteristics, and the method comprises the following steps: S01, obtaining CORS base station observation data in a strip-shaped region distributed along a longitude line, according to the high-precision coordinates of the CORS base stations and high-precision satellite orbits, clock errors and other information issued by the IGS, ionospheric electron density information at the puncture point is obtained when different CORS base stations observe the same GNSS satellite at the same moment; and S02, grouping the ionosphere electron density information obtained in the step S01 according to time to obtain ionosphere puncture point electron density information in a strip-shaped region in sequential arrangement, and fitting the electron density information at each moment to obtain an ionosphere electron density model at different moments in the strip-shaped region. The problem that in the prior art, in order to obtain a high-precision ionosphere model, dense CORS base stations need to be established, and financial resources and material resources are wasted is solved.

The invention discloses a detection method for the electron density of an ionization layer based on radar echoes. The method is realized by the following steps that (1) original data is collected and stored; (2) non-coherent scattering echoes are extracted from the ionization layer; and (3) the electron density of the ionization layer is calculated. The disclosed detection method has great significance in radar wave environment adaptation and space environment monitoring and early-warning domestically; and compared with a present special-purposed electron density detection method for the ionization layer, the method of the invention is simple and economic. The method of the invention is also high in compatibility and transplantability, and is suitable for most space monitoring radars, and the radars need only to provide signal interfaces of original echo signals, emission pulse signals, main pulse signals and sampling clock and the like.

The invention relates to a method and device for detecting the ionosphere total electron density. In a to-be-tested area, two dual-frequency GPS receiver antenna with a spacing of about 10 meters are put up to receive GPS satellite signals, and the GPS satellite signals are transmitted into two dual-frequency GPS receivers by a coaxial cable wire, satellite signals are processed by the dual-frequency GPS receiver, the received data is saved through a communications cable wire in a computer, data for one day is taken, and processing is conducted on the data using a software program. A polynomial model is established to calculate the delays of the dual-frequency GPS receiver and the satellite hardware, skewed total electron density is obtained after the removal of the delays of the dual-frequency GPS receiver and the satellite hardware, the total electron density of two skewed dual-frequency GPS receivers is integrated, through a projection function, is converted to a vertical total electron density. By the adoption of the 10 meter rank short base line based on the foundation GPS double-station layout mode, the ionosphere total electron density is detected, the accuracy is high, and data storage, management and device maintenance are easy.