348 results about "Microwave radiometer" patented technology

Apparatus and methods for characterizing atmospheric refractivity and its evolution in time and space utilizing passive radiation emission measurement devices are disclosed. Based on an instrument such as a passive microwave radiometer, ancillary meteorological measurements and other information and observations, the apparatus and methods provide useful signatures for characterizing atmospheric refractivity. The system can observe to any vector in the sky, giving directional as well as zenithal measurements of the refractivity profile, its spatial and temporal gradients, and the spatial and temporal trending of the profile and its gradients.

The invention provides a nonlinear calibrating method for a foundation microwave radiometer, and the nonlinear calibrating method can be used for realizing noise injected multi-point brightness temperature on the basis of foundation microwave radiometer noise injected two-point calibration. In the method, periodical calibration is performed on drifting of noise temperature and gain of a receiver by utilizing multi-point brightness temperature values which are acquired by two known reference targets and the other two known noise injected reference targets, and a calibration equation acquired by nonlinear factors of a foundation microwave radiometer system can be determined for real-time measurement of the target brightness temperature. Meanwhile, the invention also provides a nonlinear calibrating device for the foundation microwave radiometer, and the nonlinear calibrating device comprises a noise injection module and a system built-in calibration blackbody, wherein the noise injection module comprises a noise source, a switch and a directional coupler; and the system built-in calibration blackbody provides standard brightness temperature equivalent to the environment temperature. By utilizing the method, nonlinear errors caused by the nonlinear power characters of a detector diode can be reduced, so that the detection accuracy can be improved.

The present invention relates to an oil spill identification system and oil spill identification sensors to be used in connection with this system. The system is used primarily on fixed offshore structures, but may also be used on fixed onshore constructions. The sensor comprises a combination of a radar and at least a microwave radiometer. The data collected are transmitted to a control station. Preferably, the transmittal takes place at pixel level between the sensors and the control station. The control station processes the data received at pixel level and transmits data to an end-user, preferably through the internet. The invention also relates to a method for utilizing the system and a use of the system.

The present invention provides an application data processing method of a spaceborne microwave radiometer. According to the application processing method, by inputting the global or regional profile data and the radiation brightness-temperature values in a matrix, adopting a wavelet neural network algorithm to train the data, and comparing the outputted atmosphere humiture profile and ground/sea surface parameters with the preset threshold indexes, the back propagation of the atmosphere humiture profile and ground/sea surface parameter errors is implemented; by correcting each layer of weights in an error gradient descent manner, the work of utilizing a data set to correct the inversion parameters locally is realized, the local correction capabilities of the equipment developers and users to the inversion software parameters are improved, and further the detection and inversion precision is improved further.

The invention provides an atmosphere profile inversion method based on a foundation hyperspectral microwave radiometer, and belongs to the technical field of microwave remote sensing. The atmosphere profile inversion method based on the foundation hyperspectral microwave radiometer comprises the following steps of setting system parameters of the foundation hyperspectral microwave radiometer, acquiring background parameters and background field errors, establishing a radiation transfer model, determining atmospheric radiation transmission brightness temperature, and inverting an atmosphere profile by using the iterative process of a variational method. Through the utilization of the atmosphere profile inversion method based on the foundation hyperspectral microwave radiometer, the accurately inverted atmosphere profile can be obtained through the foundation hyperspectral microwave radiometer, and the atmosphere profile inversion method is especially suitable for multi-channel radiometers and detection situations of insufficient prior data, enables a large amount of frequency band information provided by the foundation hyperspectral microwave radiometer to be used completely, and has strong adaptability and small detection errors.

The invention relates to a full-polarization synthetic aperture microwave radiometer, comprising an antenna array, a receiver array, a correlator unit, and a control and data processing unit which are connected in turn, wherein the control and data processing unit is connected with a computer or a data interface. The invention is characterized in that the antenna array adopts a one-dimension antenna array composed of parallel dual-polarized antenna units. The technical scheme of the invention comprises realizing the full-polarization measurement of one-dimension synthetic aperture, realizing the equal incident angle measurement of synthetic aperture microwave radiometer, and realizing the two-point calibration of the synthetic aperture microwave radiometer. The one-dimension aperture synthetic technique is simpler than two-dimension aperture synthetic technique. The single channel receiver polarization switch mode can satisfy the demands of light weight and low power consumption. The dual channel receiver mode can realize the radiometer of high sensitivity.

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 method for inversing soil moisture content from AMSR-E (Advanced Microwave Scanning Radiometer-EOS) data, which can be used for the remote sensing application departments of monitoring weather and environment, managing land, monitoring a drought and a crop growing situation, monitoring disasters, and the like. The method comprises the following four steps of: firstly, simulating the most part of situations on the earth surface and establishing a database by using a theoretical model; secondly, establishing an inverse algorithm by using a simulation database; thirdly, carrying out the inverse calculation of passive microwave data AMSR-E; and fourthly, carrying out proper evaluation, analysis and modification by using observation data of a meteorological department, thereby increasing the precision and the applicability of the algorithm. The method for inversing soil moisture content from the AMSR-E data can be used for the departments of forecasting weather, monitoring environment, agricultural situations and disaster situations, and the like. The microwave radiation frequency arrangement carried by a Fengyun 3 satellite of China is basically similar to the AMSR-E, and the invention can be applied to the Fengyun 3 satellite of China and a microwave radiometer transmitted by China in the future after being modified.

The invention relates to the technical field of satellite communication and particularly relates to an acquisition method for sea ice concentration on the basis of the Ocean No. II satellite scanning microwave radiometer. The acquisition method for the sea ice concentration on the basis of the Ocean II satellite scanning microwave radiometer comprises the following steps: according to a first brightness temperature data of a typically characteristic area, a brightness temperature characteristic value is obtained; the typical characteristic area comprises a characteristic area of one-year ice, a characteristic area of multiyear ice and characteristic area of sea water; the first brightness temperature data is acquired through the Ocean II satellite scanning microwave radiometer; according to the brightness temperature characteristic value and a second brightness temperature data of a monitored area, dynamic brightness temperature characteristic value of the monitored area is acquired; the second brightness temperature data is acquired through the Ocean No. II satellite scanning microwave radiometer; according to the dynamic brightness temperature characteristic value of the monitored area, the dynamic sea ice concentration of the monitored area is acquired. The acquisition method for sea ice concentration on the basis of the Ocean II satellite scanning microwave radiometer overcomes the technical problem that the sea ice concentration of a correspondingly monitored area cannot be acquired on the basis of the data acquired by the Ocean II satellite in the prior art.

The invention relates to a data processing and controlling apparatus used for a ground-based microwave radiometer. The data processing and controlling apparatus comprises a scaling module, a data quality control module, an atmosphere parameter inversion module, a derivative data product generation module and a data management module. The scaling module is used for realizing scaling operation of the ground-based microwave radiometer, and first-level brightness temperature data are obtained. The data quality control module is used for controlling the original data collected by other apparatus. The atmosphere parameter inversion module generates a troposphere temperature profile, a boundary layer temperature profile, a relative humidity and steam density profile according to the brightness temperature data after being scaled and the voltage data of each auxiliary apparatus. The derivative data product generation module performs simulation computation on the atmosphere integration steam and cloud liquid water content through the atmosphere temperature and humidity profile provided by the history sounding data, computes cloud base temperature and height, atmosphere integration steam and the cloud liquid water content. The data management module is used for realizing internal data file backup and compiling system state information and controlling management log.

The present invention relates to the application of microwave remote sensing technology, and is especially microwave radiometer method of monitoring soil moisture. The method includes the following steps: 1. preparing operation environment and radiometer data; 2. inverting to obtain field surface dielectric constant of the observed point and forming grids; 3. calculating the soil moisture based on the dielectric constant; and 4. mapping soil moisture distribution and saving as common graph format.

The invention relates to a digital correlator. The digital correlator comprises a sampling module, a multiplexing module, a correlation calculation module, a synchronous sampling clock module and a synchronous control module, wherein the sampling module is realized by adopting an analog-digital converter with the sampling rate being equal to or higher than 5GHz; the multiplexing module, the correlation calculation module and the synchronous control module are realized on an FPGA chip with the main frequency being higher than 400MHz; different sampling units in the sampling module are used for carrying out high-speed sampling on external input signals respectively and obtaining two paths of digital signals which are input into the correlation calculation module after being multiplexed by the multiplexing module; the correlation calculation module is used for carrying out speed reduction and correlation calculation on inputted digital signals; the synchronous sampling clock module is used for ensuring consistent phase of sampling clocks reaching the different sampling units in the sampling module, and the synchronous control module is used for controlling synchronous working among the different sampling units in the sampling module.

The invention provides a sea surface salinity retrieval method and a sea surface salinity retrieval device. The sea surface salinity retrieval method comprises the following steps: simulating atmosphere top brightness temperature so as to acquire a multi-incident angle brightness temperature simulation value of an ionopause above the atmosphere layer at an L wave band, a C wave band and a K wave band of a preset multi-angle radiation model, and a backscatter coefficient simulation value of the L wave band; respectively acquiring a multi-incident angle brightness temperature measuring value of the ionopause above the atmosphere layer at the L wave band, the C wave band and the K wave band, and a backscatter coefficient measuring value of the L wave band; performing sea surface salinity retrieval calculation according to the simulated multi-incident angle brightness temperature simulation value and the backscatter coefficient simulation value of the L wave band, and the acquired multi-incident angle brightness temperature measuring value and the backscatter coefficient measuring value of the L wave band. By adopting the sea surface salinity retrieval method, the accuracy rate of the retrieval calculation result can be improved.

The invention provides a microwave high spectrum radiometer. A rotatable platform is used to adjust a rotation angle of a microwave reflector device to change working wave beam directing of a receiving antenna device to realize measuring of atmospheric radiation spectrum. Incident microwave energy is reflected in the receiving antenna device through the microwave reflector device, and directing of the antenna wave beam is changed by rotating the microwave reflector device by 360 degrees. Elevation of the antenna wave beam can be accurately measured by an elevation positioner, and when a computer or a remote computer issues a series of observation instructions of the microwave radiometer, the rotatable platform device instructs the microwave reflector device to rotate to a specified elevation and an azimuth. A microwave high spectrum digital processing and control device enables a microwave high spectrum receiver device to be arranged into a needed passage, simultaneously orders the microwave high spectrum receiver device to start to observe the sky, and then transmits observed data to the computer or the remote computer to be inverted into meteorological parameter curves.

The invention relates to a scaling method of a foundation microwave radiometer. The scaling method comprises: obtaining voltage values output through each channel in different attenuation values, calculating corresponding equivalent brightness temperature values through attenuation values, calculating system non-linear factors and noise source injection noises according to corresponding relation between each equivalent brightness temperature value and the output voltage of each channel, and completing preliminary scaling; according to sounding profile data matching with time and place, establishing a corresponding relation of atmosphere optics thickness and atmosphere quality, substituting scaling parameters, obtaining a scaling relation curve, determining the scaling parameters according to the scaling relation curve; observing cold air and cold air coupling noises at each attenuation value, obtaining voltage values output through each channel at different attenuation values and fitting the attenuation values and the voltage values; calculating the equivalent noise temperature when an antenna aligns with the cold air through the relation of the attenuation values and the output voltage values of the attenuator, and determining the brightness temperature values corresponding to the cold air observed by the foundation microwave radiometer in different time and places.

The invention provides a multi-channel microwave radiometer system control device and a control method. The control device comprises an FPGA development board part, a data acquisition circuit part, an automatic gain control (AGC) circuit part, a system switch control circuit part and a level switching circuit part, wherein the FPGA development board part receives an instruction packet of a remotecomputer through a serial bus, determines a system working mode according to an injection instruction, simultaneously provides corresponding time sequences for the data acquisition circuit part, the AGC circuit part and the system switch control circuit part, sends a control instruction to the system, controls a plurality of channels of a microwave radiometer to acquire scientific data and temperature data, and is responsible for downloading the acquired scientific data packet to the remote computer. In the invention, the control method of combining the existing FPGA development board with other control circuits is adopted, thus the multi-channel microwave radiometer system control device has the advantages of reduced cost, shortened development cycle, better flexibility and expandabilityand wider application range.

The invention relates to a spaceborne interferometic microwave radiometer comprising an earth observation antenna array, a cold sky calibration antenna, a public noise source, a noise-source multiway power divider, a cold sky multiway switch, receiver front-end multiway switches, Dick type receivers and earth observation receivers. The earth observation antenna array comprises multiple earth observation antennas, antenna beams of the earth observation antennas deviate from an antenna plane normal and obliquely point to the ground; the two earth observation receivers are mounted behind each earth observation antenna; antenna beams of the cold sky calibration antenna are opposite to the antenna beams of the earth observation antennas and constantly point to the cold sky; the cold sky calibration antenna is connected to all the receivers; the public noise source is connected with all the receivers; a matching load is mounted at the front end of each receiver; the Dick receivers are operated under the Dick mode; the earth observation receivers are connected with the cold sky calibration antenna, the earth observation antennas, the matching loads and the public noise source.

The invention discloses a multi-source satellite soil humidity inversion method which is characterized by comprising the following steps: collecting brightness temperature data of a multi-source satellite, and obtaining a uniformed brightness temperature product sequence of an identical spatial resolution; establishing a soil humidity microwave sensing inversion model, carrying out brightness temperature to emissivity conversion, and extracting grid emissivity of a microwave radiation meter scanning track one by one; ejecting and correcting influence of vegetation and ground surface roughness;converting soil dielectric constants into the emissivity, carrying out correlated thrust reversion on the converted dielectric constants and soil humidity, thereby obtaining remote sensing inversionon the soil humidity. Quasi real-time brightness temperature data observed by multiple satellite platforms are adopted as main input data, brightness temperature data of different satellite sources are cut and spliced, inversion and space-time reconstruction on moisture of soil on a surface layer are achieved, and continuous soil humidity products of high space-time resolutions can be acquired.

The invention relates to a configurable digital correlator for a complete polarization microwave radiometer system. At a radio frequency front end of the complete polarization microwave radiometer system, a signal after frequency-mixing amplification and orthogonal transformation is transformed to be a differential signal and then is input into four ultrahigh-speed ADC (Analog to Digital Converter) input ends to be converted into a digital signal after sampling conversion, and the digital signal after multi-path multiplexing is input into a digital correlative circuit; the digital correlativecircuit comprises a parameter selection module and a correlative calculation module, wherein the parameter selection module returns a command to modify a digital correlative digit parameter and an integration time parameter in an FPGA (Field Programmable Gate Array) through a serial port of a computer to configure the FPGA in real time so as to realize digital correlation from 2 bits to 12 bits and selection of the integration time from 5ms to 50ms; and the correlative calculation module executes deceleration and correlative calculation processing on the input digital signal after determiningquantization digit and the integration time and outputs a correlation result to a computer through a data format conversion and external interface circuit according to a required sequence.

The invention discloses an all-digital compensation microwave radiometer, which comprises an antenna, a matched load, a microwave switch, a full-power radiometer, a digital control unit, a communication unit and a display unit. According to the cycle detection of the input voltage of the matched antenna and the antenna and the practical temperature of the matched load, the influence on the performance of the radiometer caused by the gain uncertainty of a radiometer system and local noise fluctuation is balanced out through the digital compensation operator of the digital control unit. The all-digital compensation microwave radiometer not only greatly increases sensitivity and long-term stability, but also has simple structure and small volume; moreover, the radiometer can work for a long time after initial calibration, thereby avoiding the inconvenience of cycle calibration on ground basis, vacuous basis and satellite basis and greatly increasing target observation time and scope.

The invention relates to a complete-polarization microwave radiometer calibrating device which comprises a calibrating hot source, a calibrating cold source, a polarization separator and a phase generator. The calibrating hot source is arranged on a horizontal plane or a vertical plane, the plane where the calibrating cold source is arranged is perpendicular to the plane where the calibrating hot source is arranged, the polarization separator is arranged between the calibrating cold source and the calibrating hot source, the polarization separator forms an 45-degree angle with the horizontal plane, and the plane where the phase generator is arranged forms a certain angle with the plane where the polarization separator is arranged. The complete-polarization microwave radiometer calibrating device effectively reduces system errors and random errors and greatly reduces calibrating uncertainty.