71 results about "Occultation" patented technology

The invention discloses a system for generating a satellite navigation occultation signal. The system comprises a parameter calculating and real-time updating module, a middle-frequency navigation signal generating module, a DAC (Digital to Analog Convertor) module and an upper frequency conversion module, wherein the parameter calculating and real-time updating module is used for receiving inputdirect star observing data and occultation observing data, generating an accumulative parameters and power control codes corresponding to the direct star observing data and the occultation signal observing data respectively, compensating for the accumulative parameters of the direct star observing data and the occultation observing data, and outputting the power control codes and the compensated accumulative parameters to the middle-frequency navigation signal generating module; and the middle-frequency navigation signal generating module is used for generating a direct star digital middle-frequency simulation signal and an occultation digital middle-frequency simulation signal according to the input power control codes and the compensated accumulative parameters, and outputting to the DAC module. Due to the adoption of the system, the problems of high field experiment cost, easiness of interference and uncontrollable and unrepeatable simulation scene are solved effectively.

A multimode occulting antenna with a stable phase center comprises a reflection cavity, a lower radiation paster, an upper radiation paster, four feed probe sleeves, four feed probe inner cores and two support columns. Each feed probe sleeve comprises a metal seat and filler, one end of the metal seat is a metal column, the other end of the metal seat is a cylindrical metal cavity, and the filler is used for filling the cylindrical cavity of the metal seat. The sleeve-shaped probes are coupled with feed through four points, probes are uniformly distributed on the circumference, an aerial radiation paster consists of an upper layer and a lower layer, the lower layer is coupled with the feed through the sleeve-shaped probes, the upper layer is coupled with the feed through the lower radiation paster, the middle is supported by the metal support columns, and the reflection cavity is of a round bowl-shaped structure and higher than the upper radiation paster. The occulting antenna is excellent in performance and structure, simple and reliable in process, wide in frequency band, capable of meeting use requirements of a GPS (global positioning system), BD-2, GALILEO and GLONASS, wide in beam coverage, high in gain, stable in phase center, excellent in axial ratio performance, and applicable to a precise obscuration detection system and other high-precision detection systems.

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 relates to globe positioning system GPS receiver technical field, in particular to a method for measuring the obscuration error of dual-frequency obscuration GPS receiver. The method uses two obscuration receivers in one antenna which are same object receivers, or one is provided with known measurement error, and another one is the object receiver, to use the two measurement errors of the two receivers to obtain the measurement error of the obscuration receiver. The method comprises that 1, the GPS signal via the antenna of the obscuration receivers receive real GPS signal, 2, setting the sample rate of the receivers, 3, analyzing the data of the two receivers, 4, calculating the high-load noise ratio measurement error and averaging, via the high-quality data, 5, calculating out the integral measurement error.

The invention provides a GNSS occultation ionospheric residual correction method and system, a device and a storage medium. The method comprises the steps of: preprocessing GNSS occultation original observation data, vTEC maps data and geomagnetic field observation data to obtain GNSS occultation geometric data, ionospheric data and geomagnetic field data; based on the GNSS occultation geometric data, a three-dimensional NeUoG ionospheric mode and the ionospheric data, calculating an electron density profile at the location of an ionospheric puncture point on an incident ray side and an emergent ray side; based on the GNSS occultation geometric data, an IGRF geomagnetic field mode and the geomagnetic field data, calculating a geomagnetic field intensity profile along a signal path at the location of the ionospheric puncture point on the incident ray side and the emergent ray side; based on the electron density and the geomagnetic field intensity along the signal path, calculating a bending angle ionospheric residual profile. The method of the invention can be used in the atmospheric parameter inversion of a single GNSS occultation event, weakens the influence of the ionospheric residual, obtains a high-precision GNSS occultation curved angular profile, and is efficient and reliable.

The invention discloses an SPSA meteorological parameter solution method based on assimilation of navigation satellite occultation data. The method is characterized by comprising the following steps that a cost function of occultation data assimilation is established, the first-order approximation gradient of the cost function is calculated, the atmosphere state vector is updated by utilizing the approximation gradient, the cost function value under the present atmosphere state vector is solved, whether an iteration stop condition is met is determined, and if yes, the solution of the atmosphere state vector is obtained. It is not required to design a tangent operator and an adjoint operator of an observation operator, the solution algorithm of the cost function is greatly simplified, the efficiency and feasibility for solving the atmosphere state vector are improved, and the method can be widely applied.

The invention provides a method for forward simulation of occultation. The method is applicable to the GNSS earth atmosphere occultation exploration constellation design and analysis application. According to the method, satellite orbit parameters serve as design input, constellation construction parameters are supplemented to serve as design input, and constellation design and analysis application are facilitated; influence of atmospheric refraction is taken into comprehensive consideration in the process of occultation event judgment and positioning, and occultation measuring point positioning accuracy is improved; ground data transmission station modeling is added, and downloading timeliness of occultation exploration data can be supplemented and analyzed.

The invention discloses a variable-step-size obscuration forecasting method. The variable-step-size obscuration forecasting method comprises the steps of: firstly, defining a satellite-target source coordinate system and establishing a conversion matrix corresponding to a WGS-84 coordinate system; then establishing a criterion of obscuration events of a satellite in the satellite-target source coordinate system; if the criterion is satisfied, further judging whether a vector of a connecting line between the satellite and a target source is within an observable range of a satellite obscuration antenna; if so, considering that an obscuration event occurs, and further performing effective forecasting on the obscuration event. The obscuration generation process is converted into a geometrical problem that a fixed-point rotating ray cuts the circumference within the satellite-target source plane by adopting a coordination conversion idea, so that the physic principle of the generation of the obscuration event is revealed substantially; the variable-step-size obscuration forecasting method is a variable-step-size obscuration forecasting algorithm which can efficiently improve the calculation efficiency; through the combination with the installation of the satellite obscuration antenna, the variable-step-size obscuration forecasting method is suitable for the practical project application and is particularly suitable for forecasting the sun or the GPS obscuration event for a long time.

The invention discloses a satellite-borne occultation real-time forecasting method. The method comprises the steps of: obtaining the position velocity of a spacecraft according to the positioning device of an occultation detector; calculating the orbit parameter of the spacecraft; calculating the position velocity of the spacecraft and all navigation stars after 10s; calculating the pitch angle, the azimuth angle, the tangent point height of all navigation stars and the antenna azimuth angle of the spacecraft; judging whether the obtained pitch angle Elv, the tangent point height Hight and theantenna azimuth angle satisfy the threshold of the occultation event extrapolating the time for 30 s and 1 min, repeating the above calculation and determination processes if satisfied; and determining that the navigation star is the occultation if all are satisfied. The method of the invention adopts a continuous arc to judge the occultation event through an inertial navigation device, and enhances the accuracy of the forecasting result. The method is simple and easy to implement, and has important application value for real-time forecasting.

The invention relates to the technical fields of satellite navigation, atmospheric sounding and parallel computation, and in particular relates to a data treatment method of parallelization Abel transformation atmospheric parameters. Because no time dependence on data treatment exists among occultation events generated by an LEO asterism occultation system, the back calculation of the Abel transformation atmospheric parameter of each occultation event is mutually independent. Based on the point, the data treatment method of the parallelization Abel transformation atmospheric parameters is provided by the invention, and the back calculation of the Abel transformation atmospheric parameter is realized by adopting a high-efficiency parallelization method with fine granularity. Aiming at the condition that no time dependence exists within the back calculation process of the Abel transformation atmospheric parameter, the atmospheric parameter back calculation on the multiple occultation events is carried out by completely adopting a fine granularity parallel mode, thus the invention has the characteristics of high efficiency, simple method and high execution efficiency, is suitable for computer systems, and can effectively improve the core part of the asterism occultation data system, i.e. the work efficiency of the atmospheric parameter back calculation.

The invention discloses a cloud-base height inversion method based on radio occultation detection data, comprising the following steps of: firstly, giving statistics of distribution characteristics within the worldwide COSMIC occultation vertical sounding scope and calculating the probability of the cloud-base height inversion influenced by the COSMIC sounding scope; secondly, reading temperaturedata and water vapour pressure data from COSMIC occultation detection moist air data; thirdly, acquiring cloud-base height information with the combination of relative humidity variation profile inversion based on the method brought forward by Wang for determining the cloud-base height by using relative humidity profile data; finally, based on the method brought forward by Wang for determining the cloud-base height by using the relative humidity profile data, carrying out the cloud-base height inversion by the adoption of radiosonde detection data, and calculating the relative difference between the radiosonde cloud-base height inversion result and the COSMIC cloud-base inversion result. The cloud-base height inversion method provided by the invention makes up the defects that previous satellite remote sensing can not provide bottom cloud-base height information and the reliability of field observation is poor for the detection of the medium cloud-base height and the high cloud-base height.

The invention proposes a lighting headlamp for a motor vehicle, comprising a light source, a reflector of the elliptical type, a first focus of which is arranged in the vicinity of the source and a second focus of which is arranged in the vicinity of the focal plane of a convergent lens, and a movable mask which is mounted so as to pivot, with respect to a fixed mounting, about an overall transverse axis, and which is capable of occupying an angular occultation position, in which it is arranged substantially vertically in the vicinity of the focal plane of the lens so as to form a cutoff in the light beam produced by the headlamp, and a retracted angular position, a spring forcing the movable mask into its occultation position, wherein it also comprises at least one locking means acting between the mounting and the mask in order to hold the mask in its occultation position.

A method of positioning a plurality of radar units in a defined area amongst one or more legacy radar units that provide legacy radar coverage in the defined area is disclosed. The steps of identifying a location of each legacy radar unit, setting a threshold altitude, and determining a legacy occultation of each legacy radar unit from a landscape level up to the threshold altitude are also disclosed. Mapping the legacy occultation of the legacy radar units to provide a three dimensional occultation map in the defined area and locating gaps below the threshold altitude in the legacy radar coverage as a function of the occultation map are also disclosed. Identifying a plurality of sites as a function of the gaps where the sites are accessible to receive a radar unit is also disclosed. Determining an anticipated radar coverage of a radar unit positioned at each of the sites and determining a reduction in the gaps as a function of the anticipated radar coverage are also disclosed. Selecting sites as a function of the reduced gaps is also disclosed. X band, C band or S band radar units can be positioned at the selected sites. The threshold altitude can be 10,000 or 15,000 feet. Affected populations and costs can also be considered in radar placement.

The invention relates to a temperature and pressure profile and tangent height joint inversion method, which is characterized by establishing a prior profile, a prior covariance matrix and an observation covariance matrix; inputting geographic and geometric information observed by a satellite into a forward radiation transfer model SCIATRAN to obtain an analog value and a weight function of the temperature; by combining the analog value, the weight function of the temperature, the prior profile, the prior covariance matrix and the observation covariance matrix, and based on an optimal estimation algorithm, obtaining a temperature profile; based on the optimal estimation algorithm, realizing temperature profile inversion of an occultation sensor, and in the inversion iteration process, realizing synchronous inversion of pressure and tangent height through a hydrostatic equilibrium equation; and finally, through iteration, obtaining a temperature profile, a pressure profile and corrected tangent height.

The invention relates to a supercontinuum light source-based atmospheric multi-component laser occultation detection device. A supercontinuum laser source is utilized to generate mid-infrared supercontinuum laser signals capable of covering a plurality of atmospheric component characteristic absorption lines, and the concentration of various gas components in the atmosphere is measured with an occultation laser detection and heterodyne receiving mode; the device includes a power stabilization circuit, a supercontinuum laser light source, a first beam splitter, an energy monitoring module, an optical transmitting antenna, an optical receiving antenna, an optical fiber switch, a second beam splitter, a frequency control circuit, a local oscillation laser array, a combiner array, a photodetector array, a radio frequency receiver array, a lock-in amplifier array, and a data processing module. The device has broad application prospects in global climate and environmental change field, atmospheric chemistry field and the like.

The invention relates to a solar occultation measurement method of inversion near space atmosphere density based on X-rays. The method is characterized by simultaneously measuring unattenuated solar X-ray intensity and attenuated X-ray intensity in a solar occultation path through the X-rays so as to fit the atmosphere density in a height range of 50-200km. The method has the advantages of large detection height range, low technical complexity, easy implementation and high measurement accuracy; meanwhile, the method is capable of monitoring the response of the near space atmosphere density change to the solar activity in real time; the establishment of a three-dimensional tomographic dynamic model of the near space atmosphere density is facilitated; the requirements on atmosphere parameters of development, verification and control of a near space aircraft can be met.

The embodiment of the invention discloses an occultation exploration system and method suitable for an aerostat. The occultation exploration system comprises a positioning antenna, an occultation receiving antenna, a radio frequency processing device and an occultation processing device; the radio frequency processing device is used for acquiring GNSS (global navigation satellite system) signals received by the positioning antenna and the occultation receiving antenna, and performing intermediate frequency processing on the GNSS signals, thereby obtaining a digital intermediate frequency signal; the occultation processing device comprises a SOC (system on chip); a FPGA (field programmable gate array) is used for obtaining original measurement data according to the digital intermediate frequency signal, and inputting the original measurement data into an ARM; the ARM is used for obtaining an occultation exploration result according to the original measurement data. By adopting the high-performance SOC chip and FPGA+ARM architecture loaded thereon, the exploration system miniaturization, high integration, standardization and low-cost design are realized, and the system is suitable for the aerostats in multiple volumes, and the space resource utilization rate is improved.

The invention discloses a field operation helmet which is characterized in that sound-proof earmuffs are arranged inside the helmet, an electronic clinical thermometer occultation band is embedded in the helmet, an interphone speaker and a micro LED anti-explosion flashlight are arranged outside the helmet, a photochromic ocular lens is adopted, and reflective materials and fluorescence materials are sprayed on a helmet body. The field operation helmet integrates multiple functions, namely, a use function, a comfortably wearing function, a head safety protection function, an illuminating function, a body temperature measuring function, a camera shooting function, a communication function, a sound recording function, an eye protection function and an ear protection function. An embedded type and an outside hung type are combined to form the assembly structure of all functional assemblies, convenience and simplicity are obviously displayed, and meanwhile complex functional combination is achieved. The field operation helmet has the advantages that the categories, the number and the weight of tools which are carried by engineering workers are reduced, complexity of achieving operation through a specific function is reduced, labor intensity of the workers is lowered, and labor productivity is improved.

The embodiment of the invention discloses an aerostat-based integrated occultation and reflection detection integrated device and method. The device comprises an integrated antenna array, a GNSS direct antenna, a radio frequency signal processing circuit, a digital signal processing circuit, an anti-fuse FPGA and a FLASH memory. The integrated antenna array and the GNSS direct antenna are connected with the radio frequency signal processing circuit. The radio frequency signal processing circuit is connected with the digital signal processing circuit. The digital signal processing circuit is connected with the anti-fuse FPGA. The anti-fuse FPGA is connected with the FLASH memory. According to the technical scheme, the effects of reducing detection cost, reducing device volume, configurableresources and sharing can be realized.

The invention relates to a large aperture and multiple mode extrasolar terrestrial planet detector. The large aperture and multiple mode extrasolar terrestrial planet detector comprises branch systems of an effective load system, a structure and mechanism system, a thermal control system, a solar wing system, a power supply and distribution system, a measurement control and data transmission system, an integrated electronic system, a GNC (global navigation chart) system, a propelling system and the like. Compared with traditional satellites, the detector achieves multifunctional integrated detection of occultation photometry, radial velocity measurement, planetary atmosphere transmission spectrum measurement and multiple ultraviolet wavelength detection, has space-based extrasolar planet exploration competence, can adapt to research demands of extrasolar planets and life exploration in future, and has the advantages of being integrated, large in aperture, multiple in mode, ultrahigh in precision, ultrahigh in stability and the like.

The invention relates to a method of correcting a tangent height based on an infrared occultation sensor. The method comprises steps: first-level data are acquired through the infrared occultation sensor, wherein the first-level data comprise multiple tangent heights and an atmospheric composition; the first-level data are subjected to wave number processing to remove abnormal tangent heights in the multiple tangent heights; sensitivity analysis is carried out on multiple gases in the atmospheric composition in a wave number range; and through the sensitivity analysis, after gases which affectthe wave number in the atmospheric composition are eliminated on the basis of the wave number range, and logarithmic gradient trigonometry is adopted to correct the tangent heights in the first-leveldata. The quick tangent height correction method can perform tangent height correction based on the occultation sensor features more simply, quickly and accurately.

A single-carrier multiple-antenna occultation signal generation system includes a direct star - occultation data real-time generation unit and a direct star - occultation signal real-time generation unit. The direct star - occultation data real-time generation unit is used to generate an accumulative parameter and a power control code corresponding to direct star and occultation observation data; and the direct star - occultation signal real-time generation unit uses the inputted accumulative parameter and power control code to generate a five-way radio frequency signal output which respectively includes a direct star channel, a front neutral atmosphere channel, a front ionized layer channel, a rear neutral atmosphere channel, and a rear ionized layer channel. The single-carrier multiple-antenna occultation signal generation system can simulate a navigation positioning signal, an ionized layer occultation signal and a neutral atmosphere occultation signal, so that the single-carrier multiple-antenna occultation signal is truly realized; and the occultation signal source parallel with the simulation network can be formed to carry out the multi-star occultation signal simulation.

Provided is a satellite borne obscuration receiver quick positioning method based on a satellite platform system. A GPS receiver receives a signal of a GPS satellite constellation, processes the signal to obtain GPS ephemeris information, time information, satellite position information and GPS constellation distribution forecast information; the GPS receiver receives an auxiliary information poll instruction sent out by a satellite service dispatching unit and outputs the obtained GPS ephemeris information, time information, satellite position information and GPS constellation distribution forecast information to a first-level CAN bus of a network on a satellite; the satellite service dispatching unit outputs the GPS ephemeris information, time information, satellite position information and GPS constellation distribution forecast information to a second-level CAN bus of the network on the satellite; a satellite borne obscuration receiver receives the GPS ephemeris information, time information, satellite position information and GPS constellation distribution forecast information obtained from the second-level CAN bus of the network on the satellite and first verifies the information, and if the information is effective, then quick locating is achieved through the information. According to the satellite borne obscuration receiver quick positioning method based on the satellite platform system, the locating time for the first time in starting and work of a specified arc section of the obscuration receiver is reduced, and the availability ratio of obscuration observation data is improved.