Blackbody emissivity real-time monitoring method and device for satellite-borne microwave radiometer
By performing real-time two-point calibration using an integrated on-orbit device, the problem of the inability to monitor the emissivity of spaceborne blackbody in real time was solved. This enabled improved emissivity monitoring and calibration accuracy in a real-world on-orbit environment, ensuring the reliability and consistency of the data.
Patent Information
- Application Number
- CN202610125223.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-29
- Publication Date
- 2026-04-10
AI Technical Summary
Existing technologies cannot monitor the emissivity of spaceborne blackbody in real time in orbit, resulting in insufficient calibration accuracy, inability to trace and correct the source, and ground testing methods cannot truly reflect the in-orbit environment, leading to problems of environmental mismatch and insufficient long-term monitoring capabilities.
By using an integrated on-orbit device, real-time two-point calibration is performed using a matched load and noise source. Combined with a switch and data acquisition unit, the blackbody emissivity is monitored in real time, enabling real-time tracking and trend analysis of the blackbody emissivity, dynamic correction of the calibration benchmark, and improvement of calibration accuracy.
It enables blackbody emissivity monitoring in a real-world on-orbit environment, ensuring that the calibration benchmark is traced back to the actual physical state, correcting radiator gain drift in real time, improving calibration accuracy and data reliability, establishing a closed-loop traceability chain, and enhancing data consistency.
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Figure CN121829776A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of on-orbit calibration of microwave passive remote sensing radiometers, and particularly relates to a blackbody emissivity real-time monitoring method and device for a spaceborne microwave radiometer. BACKGROUND
[0002] With the increasing accuracy requirements of passive microwave quantitative remote sensing technology, the detection accuracy of spaceborne microwave radiometers is facing more severe challenges. Currently, spaceborne microwave radiometers generally use a two-point calibration method, taking the cosmic background (2.73K) as a low-temperature calibration source and a spaceborne blackbody as a high-temperature calibration source, and the linear calibration is used to retrieve the radiance temperature of the earth target. The accuracy of this method fundamentally depends on the accuracy of the radiance temperature of the spaceborne blackbody, which is directly determined by the physical temperature and the emissivity at the microwave frequency of the spaceborne blackbody. Therefore, the spaceborne blackbody must have a high and stable emissivity.
[0003] Currently, the calibration of the emissivity of the spaceborne blackbody completely depends on ground testing. The mainstream method is to use a set of standard radiometer systems with known accuracy in a microwave darkroom to observe standard high and low temperature blackbodies with known emissivity and the spaceborne blackbody to be tested, and to obtain the emissivity parameters of the blackbody to be tested by comparison calculation. However, this method has inherent and insurmountable limitations, which seriously restricts the traceability and accuracy of the on-orbit calibration of spaceborne microwave radiometers: First, there is an essential difference between the ground darkroom environment and the extreme space environment of the satellite in orbit, and the emissivity characteristics of the blackbody material may change with the environment. Therefore, the ground test results cannot truly and completely represent the emissivity performance of the blackbody in the actual working state in orbit.
[0004] Second, the blackbody emissivity may slowly degrade due to material aging, thermal cycling, space irradiation and other factors during long-term on-orbit operation. The existing ground test method is only a single or periodic offline measurement, and does not have the ability to continuously monitor the changes in the emissivity of the blackbody in orbit, resulting in the inability to trace and correct the calibration accuracy in orbit.
[0005] Third, this method relies on large darkroom facilities and a set of independent high-standard radiometer systems, which cannot be carried on the satellite platform, so it is not possible to perform on-orbit.
[0006] In summary, the existing technology has the defects of unrealistic test environment and inability to perform long-term monitoring in orbit, which results in the inability to obtain the emissivity of the spaceborne blackbody in the real working environment and its change rule, which has become a key bottleneck restricting the further improvement of the calibration accuracy of spaceborne microwave radiometers and the reliability of long-term data. SUMMARY
[0007] To solve the above problems, the application provides a blackbody emissivity real-time monitoring method and device for a spaceborne microwave radiometer, and through an on-orbit integrated device, real-time acquisition of on-orbit real performance parameters of the spaceborne blackbody emissivity is realized. Through periodic measurement of a driving switch, real-time tracking and trend analysis of long-term degradation rules of the blackbody emissivity are realized. Through double-reference real-time calibration and emissivity parameter dynamic correction, calibration accuracy of the radiometer and data traceability are improved. Through closed-loop monitoring and verification of the calibration reference, quantitative remote sensing data products are obtained.
[0008] The first aspect of the application provides a blackbody emissivity real-time monitoring device for a spaceborne microwave radiometer, comprising: a feed for receiving microwave radiation energy emitted by a blackbody; a matching load for generating a low-radiation brightness temperature signal of a low-temperature reference object; a noise source for generating a high-radiation brightness temperature signal of a high-temperature reference object; a radiation receiver for receiving the blackbody microwave radiation energy or the low-radiation brightness temperature signal or the high-radiation brightness temperature signal to obtain a blackbody radiation electric signal corresponding to the blackbody microwave radiation energy or a low-temperature electric signal corresponding to the low-radiation brightness temperature signal or a high-temperature electric signal corresponding to the high-radiation brightness temperature signal; a switch for selectively connecting the radiation receiver with the feed or the matching load or the noise source; a data acquisition unit for acquiring the blackbody radiation electric signal or the low-temperature electric signal or the high-temperature electric signal to obtain a blackbody radiation remote sensing signal corresponding to the blackbody microwave radiation energy or a low-temperature remote sensing signal corresponding to the low-radiation brightness temperature signal or a high-temperature remote sensing signal corresponding to the high-radiation brightness temperature signal; a radiation calibration unit for receiving the low-temperature remote sensing signal or the high-temperature remote sensing signal or the blackbody radiation remote sensing signal to obtain a temperature value and an emissivity of the blackbody through calculation.
[0009] The second aspect of the application provides a blackbody emissivity real-time monitoring method for a spaceborne microwave radiometer, applied to the blackbody emissivity real-time monitoring device for the spaceborne microwave radiometer, comprising: acquiring remote sensing data through the data acquisition unit by outputting voltage data of the radiation receiver; calculating a brightness temperature signal of the low-temperature reference object based on the remote sensing data of the low-temperature reference object, and obtaining a brightness temperature signal of the high-temperature reference object based on the high-temperature remote sensing data of the high-temperature reference object and a super-noise ratio of the noise source; calculating a gain of the radiation receiver based on the brightness temperature signal of the low-temperature reference object, the brightness temperature signal of the high-temperature reference object and the voltage data; calculating a temperature value of the blackbody based on the gain of the radiation receiver, the brightness temperature signal of the high-temperature target, and the voltage data; calculating an emissivity of the blackbody based on the remote sensing data and the temperature value of the blackbody.
[0010] Preferably, the step of acquiring voltage data by the radiation receiver and acquiring remote sensing data by the data acquisition unit further comprises: periodically switching the switcher to be connected with the feed source, the matching load, or the noise source to acquire voltage data or remote sensing data, and the specific rules are as follows: if the switcher is connected with the feed source, acquiring a voltage signal of the blackbody by the radiation receiver and acquiring remote sensing data of the blackbody by the data acquisition unit; if the switcher is connected with the matching load, acquiring a voltage signal of the low-temperature target by the radiation receiver and acquiring remote sensing data of the low-temperature target by the data acquisition unit; if the switcher is connected with the noise source, acquiring a voltage signal of the high-temperature target by the radiation receiver and acquiring remote sensing data of the high-temperature target by the data acquisition unit.
[0011] Preferably, the calculation expression for calculating the brightness temperature signal of the low-temperature target is: wherein, is an ambient temperature of the remote sensing data of the low-temperature target.
[0012] Preferably, the step of acquiring the brightness temperature signal of the high-temperature target based on the high-temperature remote sensing data of the high-temperature target and the super-noise ratio of the noise source further comprises: wherein, is the super-noise ratio, is an ambient temperature of the remote sensing data of the low-temperature target.
[0013] Preferably, the calculation expression for acquiring the gain of the radiation receiver is: wherein, , is a brightness temperature signal of the high-temperature target and is a brightness temperature signal of the low-temperature target, respectively, , is a voltage signal of the high-temperature target and is a voltage signal of the low-temperature target in the voltage data, respectively.
[0014] Preferably, the step of calculating the temperature value of the blackbody further comprises: wherein, , , , respectively are the blackbody voltage signal in the voltage data, the voltage signal of the high temperature target, the gain of the radiation receiver and the brightness temperature signal of the high temperature target.
[0015] Preferably, the calculation expression of the emissivity of the blackbody is: In the formula, , respectively are the temperature value of the blackbody and the ambient temperature of the blackbody remote sensing data.
[0016] The third aspect of the present application provides an electronic device, comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the computer program is executed by the processor to implement the blackbody emissivity real-time monitoring method for the spaceborne microwave radiometer.
[0017] The fourth aspect of the present application provides a computer readable storage medium, wherein instructions are stored on the computer readable storage medium, and the instructions are executed by a processor to implement the blackbody emissivity real-time monitoring method for the spaceborne microwave radiometer.
[0018] 1) The inherent defect that the measurement result cannot truly reflect the on-orbit performance of the blackbody due to the environmental mismatch of the ground test method is overcome. The device measures the blackbody in the real space environment to obtain the emissivity parameter of the blackbody in the real working state, so that the calibration reference is traced to the real physical state in orbit.
[0019] 2) Real-time two-point calibration is performed based on two stable internal references of the matched load and the noise source, the gain drift of the radiation receiver can be corrected in real time, the real radiation brightness temperature of the blackbody is accurately calculated in combination with the measured emissivity epsilon, and the accuracy of the calibration equation is greatly improved. The brightness temperature data of the target object obtained at each observation time can be traced back to the blackbody emissivity and the internal reference source corresponding to the time, a complete and closed on-orbit calibration trace chain is established, and the credibility and consistency of the data are enhanced. BRIEF DESCRIPTION OF DRAWINGS
[0020] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings, in which: Figure 1 It is a framework diagram of the blackbody emissivity real-time monitoring device for the spaceborne microwave radiometer in the present application; Figure 2 It is a flowchart of the blackbody emissivity real-time monitoring method for the spaceborne microwave radiometer in the present application. DETAILED DESCRIPTION
[0021] The application will be described in further detail below with reference to the drawings and specific embodiments. The advantages and features of the application will become more apparent from the following description and claims. It should be noted that the drawings are very simplified and are not drawn to scale, and are only used to facilitate, clarify and assist in the description of the embodiments of the application.
[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the application are only used to explain the relative position relationship, movement condition, etc. between the components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications will also change accordingly.
[0023] First embodiment Referring to Figure 1 The first aspect of the application provides a blackbody emissivity real-time monitoring device for a spaceborne microwave radiometer, comprising: a feed for receiving microwave radiation energy emitted by the blackbody; a matched load for generating a low-radiation brightness temperature signal of the low-temperature target; a noise source for generating a high-radiation brightness temperature signal of the high-temperature target; a radiation receiver for receiving the blackbody microwave radiation energy or the low-radiation brightness temperature signal or the high-radiation brightness temperature signal to obtain a blackbody radiation electrical signal corresponding to the blackbody microwave radiation energy or a low-temperature electrical signal corresponding to the low-radiation brightness temperature signal or a high-temperature electrical signal corresponding to the high-radiation brightness temperature signal; a switch for selectively connecting the radiation receiver with the feed or the matched load or the noise source; a data acquisition unit for acquiring a blackbody radiation remote sensing signal corresponding to the blackbody microwave radiation energy or a low-temperature remote sensing signal corresponding to the low-radiation brightness temperature signal or a high-temperature remote sensing signal corresponding to the high-radiation brightness temperature signal from the blackbody radiation electrical signal or the low-temperature electrical signal or the high-temperature electrical signal; a radiation calibration unit for receiving the low-temperature remote sensing signal or the high-temperature remote sensing signal or the blackbody radiation remote sensing signal to obtain the temperature value and the emissivity of the blackbody through calculation.
[0024] The matched load, the noise source and the switch are high-integration and small-size microwave circuit devices, which can be arranged inside the radiation receiving link and have on-orbit working capability. The radiation receiver in the device can obtain the radiation brightness temperature of the observation target in the microwave frequency band and convert the brightness temperature signal into a voltage signal for output, and the signal transmission process of the radiation receiver satisfies the linear law. In the present application, a microwave radiometer device suitable for the blackbody is used as the radiation receiver, which ensures the effectiveness of the spaceborne blackbody emissivity test results and ensures that the ground test state is consistent with the on-orbit working state.
[0025] Optionally, the data acquisition cycle of the data acquisition unit matches the switch switching cycle of the switcher, so that the blackbody remote sensing data, the low-temperature remote sensing data and the high-temperature remote sensing data are acquired in one switch cycle, and the blackbody voltage signal, the low-temperature target voltage signal and the high-temperature target voltage signal output by the radiation receiver are matched and transmitted to the data acquisition unit.
[0026] The blackbody emissivity real-time monitoring device for the spaceborne microwave radiometer is composed of seven parts, i.e., a feed source, a switcher, a matching load, a noise source, a radiation receiver, a data acquisition unit and a radiation calibration unit. The feed source, the switcher, the matching load, the noise source and the radiation receiver are connected by a waveguide structure, and the radiation receiver, the data acquisition unit and the radiation calibration unit are connected by a cable. A thermistor is used as a temperature sensor of the matching load, the noise source and the spaceborne blackbody to be measured to acquire temperature data. After the device is built, the radiation receiver, the data acquisition unit and the radiation calibration unit are powered on and started, and the emissivity of the blackbody is measured in real time after the working state is stable.
[0027] The microwave circuit including the matching load, the noise source and the switcher is integrated on the satellite, so that the monitoring device is stably carried on the satellite platform for a long time and has working capability. The switcher is periodically switched and the data is synchronously acquired, so that all the temperature and voltage signals of the blackbody and the high- and low-temperature reference sources are quickly and synchronously acquired in one measurement cycle. The spaceborne microwave radiometer matched with the blackbody is used as the radiation receiver, so that the consistency between the ground test and the on-orbit working state is realized, and the effectiveness and direct applicability of the emissivity test result are ensured. The radiation calibration unit processes the synchronously acquired temperature and voltage data in real time, so that the on-line and real-time calculation and output of the radiation brightness temperature and the emissivity of the spaceborne blackbody are realized.
[0028] Second embodiment Reference Figure 2 The second aspect of the present application provides a blackbody emissivity real-time monitoring method for a spaceborne microwave radiometer, which is applied to the blackbody emissivity real-time monitoring device for the spaceborne microwave radiometer and includes the following steps. The voltage data are output by the radiation receiver, and the remote sensing data are acquired by the data acquisition unit; The brightness temperature signal of the low-temperature target is calculated based on the remote sensing data of the low-temperature target, and the brightness temperature signal of the high-temperature target is acquired based on the high-temperature remote sensing data of the high-temperature target and the super-noise ratio of the noise source; The gain of the radiation receiver is calculated based on the brightness temperature signal of the low-temperature target, the brightness temperature signal of the high-temperature target and the voltage data; The temperature value of the blackbody is calculated based on the gain of the radiation receiver, the brightness temperature signal of the high-temperature target and the voltage data; The emissivity of the blackbody is acquired based on the remote sensing data and the temperature value of the blackbody.
[0029] Preferably, the switching period of the switcher is set to be the switching period, the blackbody is provided with a temperature control strategy, and the temperature control strategy is that the temperature change rate of the blackbody is ≤0.2℃ / h, so that the switching period of the switcher is less than the blackbody temperature change time. The switching period of the switcher in the embodiment is set to be 1.8s, and can also be other parameters. The radiation receiver collects the blackbody signal of the microwave radiation energy, the low-radiation brightness temperature signal and the high-radiation brightness temperature signal in one period, respectively receives the blackbody voltage signal, the voltage signal of the low-temperature target and the voltage signal of the high-temperature target through the data acquisition unit, and simultaneously collects the corresponding telemetry data.
[0030] By accurately matching the switching period of the switch and the blackbody thermal stabilization time, the blackbody physical temperature is approximately constant in a single measurement process, which provides a key prerequisite for accurate calculation of the emissivity. By designing the standardized calculation process of obtaining the reference brightness temperature, calculating the gain of the radiation receiver, calibrating the blackbody brightness temperature and solving the emissivity, efficient and reliable calculation from the original signal to the final performance parameter is realized. By using the inherent engineering parameter of the noise source excess noise ratio (ENR), the device physical temperature telemetry value is accurately converted into a standard high-temperature radiation brightness temperature signal, which ensures the accuracy and traceability of the reference.
[0031] Preferably, the step of acquiring voltage data through the radiation receiver and acquiring telemetry data through the data acquisition unit further comprises: Periodically switching the switcher to be connected with the feed source, the matching load and the noise source to acquire voltage data or remote sensing data, and the specific rules are as follows: if the switcher is connected with the feed source, the blackbody voltage signal is acquired through the radiation receiver, and the blackbody telemetry data is acquired through the data acquisition unit; if the switcher is connected with the matching load, the voltage signal of the low-temperature target is acquired through the radiation receiver, and the low-temperature telemetry data is acquired through the data acquisition unit; if the switcher is connected with the noise source, the voltage signal of the high-temperature target is acquired through the radiation receiver, and the high-temperature telemetry data is acquired through the data acquisition unit.
[0032] Through programmed periodical switching of the switcher among the feed source, the matching load and the noise source, the order and complete collection of the high-temperature and low-temperature reference benchmark signals and the blackbody signal to be measured are realized, which provides a complete data basis for performing accurate two-point calibration. By synchronously collecting the voltage signal and the physical temperature telemetry data of the corresponding target in each switching state, strict one-to-one correspondence between the signal and the temperature data is realized, and the matching error caused by different time is eliminated from the source. Through high-speed and predetermined switching rules, fast polling collection of the three key target signals is realized, which provides stable and continuous data flow for real-time calculation and output of the emissivity.
[0033] Preferably, the calculation expression for calculating the brightness temperature signal of the low-temperature target is: wherein, the ambient temperature of the remote sensing data of the low temperature target.
[0034] The expression simplifies the thermal radiation physical process into a deterministic equation based on the physical characteristics of the matched load. This makes the system obtain a low temperature reference signal with accuracy only depending on the accuracy of temperature measurement and long-term stability, which provides a reliable starting point for the subsequent two-point calibration calculation. The expression avoids introducing additional and possibly changing parameters, and directly anchors the accuracy of the low temperature reference to a single measurement of ambient temperature. The simplified calculation model reduces error sources and makes the traceability path of the entire calibration link clear and direct, improving the reliability and credibility of the final emissivity calculation result.
[0035] Preferably, the step of obtaining the brightness temperature signal of the high temperature target based on the high temperature remote sensing data of the high temperature target and the excess noise ratio of the noise source further comprises: wherein, the excess noise ratio, the ambient temperature of the remote sensing data of the low temperature target.
[0036] The excess noise ratio in the embodiment is 25 dB. The brightness temperature signal of the high temperature target , while matching the load brightness temperature signal. The formula combines the physical characteristics of the noise source with the ambient temperature measurement value to accurately calculate the equivalent radiation brightness temperature output when it is turned on. It provides a high temperature reference signal with accuracy guaranteed by ENR calibration accuracy and temperature measurement accuracy, which together with the low temperature reference forms two highly reliable calibration bases. The ambient temperature in the formula is a real-time measurement value, which makes the calculated high temperature brightness temperature automatically adjust to the temperature change of the environment where the noise source is located, thereby eliminating the influence of ambient temperature drift on the high temperature reference signal and ensuring the long-term absolute accuracy of the reference. The excess noise ratio of the noise source and the ambient temperature of the remote sensing data of the low temperature target.
[0037] Preferably, the calculation expression for obtaining the gain of the radiation receiver is: wherein, , are the brightness temperature signal of the high temperature target and the brightness temperature signal of the low temperature target, respectively, , are the voltage signal of the high temperature target and the voltage signal of the low temperature target in the voltage data, respectively.
[0038] The two absolute known radiation brightness temperature references and their corresponding voltage outputs are used to realize real-time and online calibration of the transmission gain of the radiation receiver system. The gain determined by the two-point calibration method is used to accurately and linearly trace back the voltage signal output by the radiation receiver to the radiation brightness temperature physical quantity, thereby providing an accurate conversion coefficient for subsequent calculation of the real radiation brightness temperature of the blackbody. By recalculating the gain in each measurement period, real-time compensation and correction of the gain drift of the radiation receiver are realized, thereby ensuring long-term stability and reliability of the entire measurement link. The complex receiver response characteristics are characterized by a single gain parameter that can be updated in real time through algebraic relationship, thereby simplifying the system model and making the calibration process automatic and standardized, and ensuring the repeatability and consistency of the calculation results.
[0039] Preferably, the step of calculating the temperature value of the blackbody further comprises: In the formula, , , , are the voltage data of the blackbody voltage signal, the voltage signal of the high-temperature reference, the gain of the radiation receiver, and the brightness temperature signal of the high-temperature reference, respectively.
[0040] The voltage signal of the blackbody is directly and accurately converted into its real on-orbit radiation brightness temperature by using the real-time calibrated receiver gain and the known high-temperature reference brightness temperature, thereby completing the calibration of the core observation quantity. Through the calculation model, the accuracy of the blackbody radiation brightness temperature is anchored to the high-precision high-temperature reference and the self-calibrated system, which are updated in real time in each measurement period. This step can automatically compensate and correct the system error caused by environmental changes or device aging, thereby ensuring that the obtained blackbody radiation brightness temperature is accurate and stable in the long term. Through the standardized linear inversion calculation, the complex radiation measurement process is converted into deterministic algebraic operation, thereby providing core algorithm support for realizing real-time and automatic output of the blackbody radiation brightness temperature.
[0041] Preferably, the calculation expression for obtaining the emissivity of the blackbody is: In the formula, , are the temperature value of the blackbody and the environmental temperature of the blackbody remote sensing data, respectively.
[0042] The real emissivity of the spaceborne blackbody is directly and essentially quantified by dividing the real-time calibrated blackbody radiation brightness temperature by its independently measured physical temperature. The real-time calculated emissivity value provides an instant and quantitative core criterion for judging the current performance state and long-term degradation trend of the blackbody, and realizes a key leap from monitoring signals to evaluation. Since the calculation does not depend on any complex theoretical model or assumption, but only on the ratio of two directly measured values, the acquisition process of the key parameter of emissivity is direct, transparent, and the result has high reliability and clear physical meaning.
[0043] Third embodiment The third aspect of the present application provides an electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, and the computer program is executed by the processor to implement the blackbody emissivity real-time monitoring method for a spaceborne microwave radiometer of any one of the above.
[0044] By solidifying the real-time monitoring method into an executable computer program and deploying it in a standard electronic device, the entire monitoring process is fully automated, highly reliable, and stably executed on orbit.
[0045] Fourth embodiment The fourth aspect of the present application provides a computer readable storage medium, and the computer readable storage medium stores instructions, and the instructions are executed by a processor to implement the blackbody emissivity real-time monitoring method for a spaceborne microwave radiometer of any one of the above.
[0046] By storing the execution instructions of the real-time monitoring method in the computer readable storage medium, the method is programmed, stably stored, and reliably loaded, ensuring that the monitoring system can repeatedly and consistently call and execute the complete calibration and calculation process during on-orbit operation.
[0047] In the description of the present application, it should be noted that the positions or location relationships indicated by the terms "inner", "outer" and the like are based on the positions or location relationships shown in the drawings, or the positions or location relationships of the products of the present application when they are usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", etc. are only used for differentiation and description, and cannot be understood as indicating or implying relative importance.
[0048] It should be noted that, unless otherwise explicitly specified and limited, the terms "set", "connected" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium; can be internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.
[0049] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific implementation of the system and device described above can refer to the corresponding process in the foregoing method embodiments.
[0050] The embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the above-described embodiments. Even if various changes are made to the present application, as long as the changes fall within the scope of the claims of the present application and the equivalent technology, they still fall within the protection scope of the present application.
Claims
1. A blackbody emissivity real-time monitoring device for a spaceborne microwave radiometer, characterized by, The method comprises the following steps: a feed source for receiving microwave radiation energy emitted by a blackbody; a matched load for generating a low-radiation brightness temperature signal of a low-temperature target; a noise source for generating a high-radiation brightness temperature signal of a high-temperature target; a radiation receiver for receiving the blackbody microwave radiation energy or the low-radiation brightness temperature signal or the high-radiation brightness temperature signal to obtain a blackbody radiation electric signal corresponding to the blackbody microwave radiation energy or a low-temperature electric signal corresponding to the low-radiation brightness temperature signal or a high-temperature electric signal corresponding to the high-radiation brightness temperature signal; a switcher for selectively connecting the radiation receiver with the feed source or the matched load or the noise source; a data acquisition unit for acquiring the blackbody radiation electric signal or the low-temperature electric signal or the high-temperature electric signal to obtain a blackbody radiation remote sensing signal corresponding to the blackbody microwave radiation energy or a low-temperature remote sensing signal corresponding to the low-radiation brightness temperature signal or a high-temperature remote sensing signal corresponding to the high-radiation brightness temperature signal; a radiation calibration unit for receiving the low-temperature remote sensing signal or the high-temperature remote sensing signal or the blackbody radiation remote sensing signal to obtain a temperature value and an emissivity of the blackbody through calculation.
2. A blackbody emissivity real-time monitoring method for a spaceborne microwave radiometer, applied to the blackbody emissivity real-time monitoring device for a spaceborne microwave radiometer in claim 1, characterized in that, The method comprises the following steps: acquiring remote sensing data through the data acquisition unit by outputting voltage data through the radiation receiver; calculating a brightness temperature signal of the low-temperature target based on low-temperature remote sensing data of the low-temperature target and obtaining a brightness temperature signal of the high-temperature target based on high-temperature remote sensing data of the high-temperature target and an excess noise ratio of the noise source; obtaining a gain of the radiation receiver through calculation based on the brightness temperature signal of the low-temperature target, the brightness temperature signal of the high-temperature target and the voltage data; obtaining a temperature value of the blackbody through calculation based on the gain of the radiation receiver, the brightness temperature signal of the high-temperature target and the voltage data; obtaining an emissivity of the blackbody based on the remote sensing data and the temperature value of the blackbody.
3. The method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer of claim 2, wherein, The step of acquiring voltage data through the radiation receiver and acquiring remote sensing data through the data acquisition unit further comprises the following steps: periodically switching the switcher to be connected with the feed source, the matched load and the noise source to acquire voltage data or remote sensing data, and the specific rules are as follows: if the switcher is connected with the feed source, acquiring a blackbody voltage signal through the radiation receiver and acquiring blackbody remote sensing data through the data acquisition unit; if the switcher is connected with the matched load, acquiring a low-temperature target voltage signal through the radiation receiver and acquiring low-temperature remote sensing data through the data acquisition unit; if the switcher is connected with the noise source, acquiring a high-temperature target voltage signal through the radiation receiver and acquiring high-temperature remote sensing data through the data acquisition unit.
4. The method for real-time monitoring of blackbody emissivity for spaceborne microwave radiometers of claim 2, wherein, The calculation expression for calculating the brightness temperature signal of the low-temperature target is as follows: In the formulae, Ambient temperature of the remote sensing data for the cryogenic target.
5. The method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer of claim 2, wherein, The step of obtaining the brightness temperature signal of the high-temperature target based on the high-temperature remote sensing data of the high-temperature target and the excess noise ratio of the noise source further comprises the following steps: wherein is the super- noise ratio, is the ambient temperature of the cryogenic remote sensing data of the cryogenic subject.
6. The method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer of claim 2, wherein, The calculation expression for obtaining the gain of the radiation receiver is as follows: wherein , are the luminance signals of the high temperature object, respectively, the low temperature object, , are the voltage signals of the high temperature object, respectively, the low temperature object, in the voltage data.
7. The method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer of claim 2, wherein, The step of obtaining the temperature value of the blackbody through calculation further comprises the following steps: wherein , , , are the blackbody voltage signal, the high-temperature target voltage signal, the gain of the radiation receiver and the high-temperature target brightness temperature signal in the voltage data, respectively.
8. The method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer of claim 2, wherein, The calculation expression for obtaining the emissivity of the blackbody is as follows: wherein , are the temperature values of the black body, the ambient temperature of the black body telemetry data, respectively.
9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The computer program is executed by the processor to realize the blackbody emissivity real-time monitoring method for the satellite-borne microwave radiometer according to any one of claims 2-8.
10. A computer-readable storage medium having stored thereon instructions, the instructions comprising, The instructions, when executed by the processor, implement the method for real-time monitoring of blackbody emissivity for a spaceborne microwave radiometer as claimed in any one of claims 2-8.