An In-Orbit Calibration Method and System for the Emissivity of a Geostationary Orbit Microwave Radiometer Antenna

Abstract

The present invention discloses an on-orbit calibration method for the emissivity of a geostationary orbit microwave radiometer antenna, including: calculating the transmission equation of the antenna cascaded reflector according to the transmission equations of the three reflectors of the microwave radiometer antenna; obtaining the microwave loss equation of the antenna cascaded link according to the two-point calibration equation of the feed port surface and the transmission equation of the antenna cascaded reflector; using the antenna temperature control system to control the temperature gradients of the three reflectors of the antenna to the target values at the same time, and using the temperature control system to obtain the line-level cascaded losses corresponding to the temperature states of the two sets of antenna reflectors. Based on the microwave loss equation of the antenna cascaded link and the physical temperature corresponding spectral power density formula, calculate the relationship parameters between the surface reflectivity of the three reflectors of the antenna and the working surface temperature function. Realize the on-orbit real-time correction of the antenna self-radiation, conduct full cold sky observations on orbit by the microwave radiometer, and accurately obtain the antenna reflectivity and its function of changing with temperature.

Description

Technical Field

[0001] The present invention belongs to the technical field of on-orbit antennas, and particularly relates to a method, system, device and storage medium for on-orbit calibration of the emissivity of a geostationary orbit microwave radiometer antenna. Background Art

[0002] The large-aperture microwave radiometer is a geostationary orbit microwave payload. By monitoring the atmosphere and clouds at high frequencies, the vertical profiles of atmospheric temperature and humidity in the regions under typhoon, precipitation, thick cloud, thin cloud and clear sky conditions can be obtained, serving to improve weather analysis and forecasting, especially the accuracy of nowcasting and regional numerical weather forecasting; by monitoring typhoons, severe convections and other high-impact weather disasters at high frequencies in a three-dimensional manner, it provides services for meteorological disaster early warning and prediction of secondary disasters; by monitoring heavy precipitation, floods, high temperatures, cold snaps in real time and dynamically, it provides information services for ecological and environmental monitoring and governance; by generating various atmospheric physical parameters and quantitative products, it provides services for agriculture, aviation, aerospace, ocean, water conservancy, for national defense security, and for scientific research. Whether the geostationary orbit microwave radiometer can obtain valuable detection data, achieve quantitative applications and real operational use during on-orbit operation mainly depends on whether the microwave radiometer can be accurately calibrated. Currently, there are mainly two calibration methods for on-orbit microwave radiometers. One is the feed aperture calibration method represented by SSM / I, AMSR, TMI, etc., and the calibration path does not include the antenna. The other is the antenna aperture calibration method represented by ATMS. For the entire payload, the transmission paths of the calibration signal and the scene signal are exactly the same, which helps to improve the calibration accuracy.

[0003] The antenna aperture of the geostationary orbit microwave radiometer is 5m, and the important working frequency bands are 54GHz, 183GHz, and 425GHz. The antenna consists of three reflecting surfaces and does not participate in the calibration path. The external heat flux environment outside the geostationary orbit is complex. The temperature fluctuation range of the antenna reflecting surface is -130°C to +130°C, and the temperature gradient is large at the same moment. The antenna reflectivity changes greatly with temperature, and the self-radiation of the antenna has a great impact on the system calibration accuracy. The antenna reflecting surface cannot be tested for the emissivity on the ground with full frequency band, full temperature and high precision, resulting in large differences in the basic values of the antenna self-radiation correction in orbit and large residuals after self-radiation correction, seriously affecting the system calibration accuracy and unable to meet the requirements of high-precision detection. Summary of the Invention

[0004] The object of the present invention is to provide a method for on-orbit calibration of the emissivity of a geostationary orbit microwave radiometer antenna, realizing real-time on-orbit correction of the self-radiation of the antenna, performing full cold sky observations on-orbit by the microwave radiometer, and accurately obtaining the antenna reflectivity and its function of changing with temperature. The forward radiation pattern of the radiometer antenna and the cold sky mirror observes the cold sky, and the backward radiation pattern of the three reflecting surfaces of the antenna observes the cold sky. An antenna temperature measurement system and an antenna temperature control system are used to obtain two sets of working conditions with the best temperature gradients of the antenna reflecting surface. Combining the two-point calibration equation of the feed port surface, the antenna cascade loss under the two sets of working conditions is obtained. Combining the measured value of the working surface temperature of the reflecting surface, the constant term coefficient and the first-order term coefficient of the linear function of the antenna reflectivity changing with the working temperature are established. According to the linear function of the antenna reflectivity and temperature, the reflectivity at any working temperature within -130°C to +130°C of the reflecting surface can be obtained in real time, and then the self-radiation of the antenna can be corrected to improve the calibration accuracy of the system.

[0005] To solve the above problems, the technical solution of the present invention is: a method for on-orbit calibration of the emissivity of a geostationary orbit microwave radiometer antenna, including: calculating the antenna cascade reflecting surface transmission equation according to the transmission equations of the three reflecting surfaces of the microwave radiometer antenna; obtaining the microwave loss of the antenna cascade link according to the two-point calibration equation of the feed port surface and the antenna cascade reflecting surface transmission equation Equation; using the antenna temperature control system, controlling the temperature gradients of the three reflecting surfaces of the antenna to the target value at the same time, and using the temperature control system to obtain the line cascade loss corresponding to the temperature states of the two sets of antenna reflecting surfaces Based on the microwave loss Equation and the physical temperature corresponding spectral power density formula, calculate the relationship parameters of the surface reflectivity and the working surface temperature function of the three reflecting surfaces of the antenna.

[0006] Preferably, the calculating the antenna cascade reflecting surface transmission equation according to the transmission equations of the three reflecting surfaces of the microwave radiometer antenna includes: the main reflecting surface transmission equation is: Among them, is the average spectral power density output by the main reflecting surface of the antenna, is the average spectral power density input forward by the main reflecting surface of the antenna, is the average spectral power density input backward by the main reflecting surface, the spectral power density corresponding to the physical temperature of the main reflecting surface, η1 is the forward radiation efficiency of the main reflecting surface, η2 is the forward radiation efficiency of the first sub-reflecting surface, and ρ1 is the reflectivity of the main reflecting surface of the antenna; the transmission equation of the first sub-reflecting surface is: Among them, the above formula is the average spectral power density output by the first sub-reflecting surface of the antenna, is the average spectral power density input backward by the first sub-reflecting surface, The physical temperature of the first sub-reflector corresponds to the spectral power density, η3 is the forward radiation efficiency of the second sub-reflector, and ρ2 is the reflectivity of the first sub-reflector. The transmission equation of the second sub-reflector is: in, is the average spectral power density output by the second sub-reflector of the antenna, is the average spectral power density of the second sub-reflector backward input, The physical temperature of the second sub-reflector corresponds to the spectral power density, and ρ2 is the reflectivity of the second sub-reflector. Substitute the transmission equation of the main reflector into the transmission equation of the first sub-reflector, and then substitute the transmission equation of the first sub-reflector into the transmission equation of the second sub-reflector to obtain the transmission equation of the antenna cascade reflector:

[0007] Preferably, the influence of the input average spectral power density of the antenna main reflector, the first sub-reflector, and the second sub-reflector is ignored, and the transmission equation of the antenna cascade reflector is simplified to:

[0008] Preferably, the antenna cascade link microwave loss is obtained according to the two-point calibration equation of the feed port surface and the antenna cascade reflection surface transmission equation. The equations include: The two-point calibration equation of the feed port surface is: in, is the cold sky spectral power density, and the cold sky background radiation brightness temperature is T c =2.73K, Spectral power density corresponding to the physical temperature of the cold air reflector C S is the output count of the feed aperture observation antenna, C W is the output count of the heat source on the feed aperture observation satellite, C C is the output count of the heat source on the feed aperture observation satellite, ρ C is the reflectivity of the cold air reflector. In the ground vacuum calibration test, the output counts of the vacuum low-temperature variable temperature source observed through the feed port and the cold air reflector are compared to accurately obtain ρ. C Value, η C Precise ground testing of the forward radiation efficiency of cold air reflectors;

[0009] Antenna cascade link microwave loss The equation is:

[0010]

[0011] Preferably, based on the microwave loss of the antenna cascade link The equation and the spectral power density formula corresponding to the physical temperature are used to calculate the parameters of the function relationship between the surface reflectivity of the three reflector surfaces of the antenna and the operating surface temperature, including: The linear functions of the surface reflectivity of the three reflector surfaces of the antenna and the operating surface temperature are the same: where a and b are the constant term coefficient and the first-order term coefficient of the linear function of the surface reflectivity of the antenna and the temperature respectively; Substitute the linear function of the surface reflectivity of the three reflector surfaces of the antenna and the operating surface temperature into the microwave loss of the antenna cascade link equation, and obtain: where The spectral power densities corresponding to the physical temperatures of the main reflector surface, the first sub-reflector surface, and the second sub-reflector surface of the antenna are respectively: Based on the adoption of the antenna temperature control system, the temperature gradients of the three reflector surfaces of the antenna are respectively controlled to the target values at the same time, and the line-level cascade losses corresponding to the temperature states of the two sets of antenna reflector surfaces are obtained by using the temperature control system Calculate the coefficients a and b, so as to obtain the function relationship between the surface reflectivity of the three reflector surfaces of the antenna and the operating surface temperature, and then correct the self-radiation of the antenna.

[0012] Based on the same inventive concept, the present invention provides an on-orbit calibration system for the emissivity of a geostationary orbit microwave radiometer antenna, including: a cascade reflection calculation module, configured to calculate the antenna cascade reflector transmission equation according to the transmission equations of the three reflector surfaces of the microwave radiometer antenna; a microwave loss calculation module, configured to obtain the microwave loss of the antenna cascade link according to the two-point calibration equation of the feed port plane and the antenna cascade reflector transmission equation equation; a parameter calculation module, configured to use the antenna temperature control system to control the temperature gradients of the three reflector surfaces of the antenna to the target values at the same time, and use the temperature control system to obtain the line-level cascade losses corresponding to the temperature states of the two sets of antenna reflector surfaces Based on the microwave loss of the antenna cascade link equation and the spectral power density formula corresponding to the physical temperature, calculate the parameters of the function relationship between the surface reflectivity of the three reflector surfaces of the antenna and the operating surface temperature.

[0013] Based on the same inventive concept, the present invention provides an electronic device, including: a memory, the memory is used to store a processing program; a processor, when the processor executes the processing program, implements the on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna.

[0014] Based on the same inventive concept, the present invention provides a readable storage medium, on which a processing program is stored, and when the processing program is executed by a processor, the on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna is implemented.

[0015] Due to the adoption of the above technical solutions, the present invention has the following advantages and positive effects compared with the prior art:

[0016] 1. The on-orbit calibration method for the emissivity of the antenna of the geostationary orbit microwave radiometer in the embodiment of the present invention has the technical characteristics of full temperature, full frequency band, and high precision. It can obtain the variation function of the reflectivity of the three reflecting surfaces of the antenna at any operating temperature within -130°C to +130°C with respect to the operating surface temperature on orbit, and perform real-time correction on the self-radiation of the antenna in the normal operating mode of the microwave radiometer, greatly improving the system calibration accuracy and solving the problem of full temperature, full frequency band, and high-precision emissivity testing on the ground.

[0017] 2. The on-orbit calibration method for the emissivity of the antenna of the geostationary orbit microwave radiometer in the embodiment of the present invention has a certain generality. It can not only be used for on-orbit calibration of the emissivity of the three-reflecting-surface antenna of the geostationary orbit microwave radiometer, but also be widely applied to on-orbit calibration of the emissivity of the single-reflecting-surface antenna of the low-earth orbit microwave radiometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the antenna of the geostationary orbit microwave radiometer of the present invention;

[0019] Figure 2 is a flowchart of the on-orbit calibration method for the emissivity of the antenna of the geostationary orbit microwave radiometer of the present invention;

[0020] Figure 3 is a graph of the function of the antenna reflectivity varying with temperature of the present invention.

[0021] DESCRIPTION OF THE REFERENCE NUMERALS:

[0022] 21: main reflecting surface of the antenna, 22: first sub-reflecting surface of the antenna; 23: second sub-reflecting surface of the antenna; 3: feed port surface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following further details a method and system for on-orbit calibration of the emissivity of the antenna of a geostationary orbit microwave radiometer proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will be clearer according to the following description and the claims.

[0024] Refer to Figure 1 , the schematic diagram of the antenna of the geostationary orbit microwave radiometer, Figure 2 is a schematic diagram of the on-orbit calibration method for the emissivity of the antenna of the geostationary orbit microwave radiometer.

[0025] The satellite maneuvers at a certain angle in orbit, and the main reflecting surface, the first sub-reflecting surface, and the second sub-reflecting surface of the antenna all observe the cold sky backward. The transmission equation during cold sky observation is as follows:

[0026] 1. Transmission equation for the main reflecting surface of the antenna observing the cold sky backward:

[0027] The average spectral power density of the cold sky observed from the back of the main reflector of the antenna. The average spectral power densities of the cold sky in the three frequency bands of 54 GHz, 183 GHz, and 425 GHz are respectively:

[0028] The back radiation efficiencies of the main reflector of the antenna are respectively: η2 - η1 = 0.015 @ f = 54 GHz, η2 - η1 = 0.001 @ f = 183 GHz, η2 - η1 = 0.001 @ f = 425 GHz;

[0029] The average input spectral power densities of the cold sky observed from the back of the main reflector of the antenna are respectively:

[0030] Therefore, when observing the cold sky with the antenna, the last term of the cold sky transmission equation observed from the back of the main reflector of the antenna is not greater than 0.024 K, and the influence can be ignored and simplified to:

[0031] 2. Cold sky transmission equation for the back observation of the first sub-reflector of the antenna:

[0032] The average spectral power density of the cold sky observed from the back of the first sub-reflector of the antenna The average spectral power densities of the cold sky in the three frequency bands are respectively:

[0033] The back radiation efficiencies of the first sub-reflector of the antenna are respectively: η3 - η2 = 0.01 @ f = 54 GHz, η3 - η2 = 0.001 @ f = 183 GHz, η3 - η2 = 0.001 @ f = 425 GHz;

[0034] The average input spectral power densities of the cold sky observed from the back of the first sub-reflector of the antenna are respectively:

[0035] Therefore, when observing the cold sky with the antenna, the last term of the cold sky transmission equation observed from the back of the first sub-reflector of the antenna is not greater than 0.016 K, and the influence can be ignored and simplified to:

[0036] 3. Cold sky transmission equation for the back observation of the second sub-reflector of the antenna:

[0037] The average spectral power density of the cold sky observed from the back of the second sub-reflector of the antenna The average spectral power densities of the cold sky in the three frequency bands of 54 GHz, 183 GHz, and 425 GHz are respectively:

[0038] The backward radiation efficiencies of the second secondary reflector of the antenna are respectively: 1 - η3 = 0.01 @ f = 54 GHz, 1 - η3 = 0.001 @ f = 183 GHz, 1 - η3 = 0.001 @ f = 425 GHz;

[0039] The average spectral power density of the backward input of the second secondary reflector of the antenna is respectively:

[0040] Therefore, when observing the cold sky with the antenna, the last term of the backward observation cold sky transfer equation of the second secondary reflector of the antenna is not greater than 0.016 K, and the influence can be ignored and can be simplified as:

[0041] Substitute the above backward observation cold sky transfer equation of the main reflector of the antenna into the backward observation cold sky transfer equation of the first secondary reflector of the antenna, and then substitute the backward observation cold sky transfer equation of the first secondary reflector of the antenna into the backward observation cold sky transfer equation of the second secondary reflector of the antenna. Therefore, the cascade transfer equation of the full cold sky observation of the antenna can be expressed as:

[0042] A linear function of the surface reflectivity and temperature of the antenna is established, and the coefficients are a and b respectively, as follows:

[0043]

[0044]

[0045]

[0046] According to the temperature field distribution in the full cold sky observation state of the antenna reflector, two sets of temperature field distributions are selected, as follows:

[0047]

[0048]

[0049]

[0050] According to the microwave loss of the antenna cascade link

[0051]

[0052] Assume the losses under two sets of temperature field distributions are 5.27 K and 3.35 K respectively;

[0053] According to two sets of loss values and their corresponding temperature field distributions, calculate the coefficients a and b of the linear function of the antenna surface reflectivity and temperature. a = 0.99827 and b = -0.00001;

[0054] See Figure 3 , the function graph of the antenna reflectivity varying with temperature, that is: This curve is basically the same as the curve of the 425 GHz antenna reflectivity varying with temperature.

[0055] Based on the same concept, the present invention also provides a system for on-orbit calibration of the emissivity of a geostationary orbit microwave radiometer antenna, including: a cascaded reflection calculation module for calculating the transmission equation of the antenna cascaded reflecting surface according to the transmission equations of the three reflecting surfaces of the microwave radiometer antenna; a microwave loss calculation module for obtaining the microwave loss of the antenna cascaded link according to the two-point calibration equation of the feed port surface and the transmission equation of the antenna cascaded reflecting surface equation; a parameter calculation module for using the antenna temperature control system to control the temperature gradients of the three reflecting surfaces of the antenna to the target values at the same time, and obtaining the line cascaded losses corresponding to the temperature states of the two sets of antenna reflecting surfaces by using the temperature control system Based on the microwave loss equation of the antenna cascaded link and the physical temperature corresponding spectral power density formula, calculate the relationship parameters of the surface reflectivity of the three reflecting surfaces of the antenna and the operating surface temperature function.

[0056] Based on the same concept, the present invention also provides an electronic device, including: a memory for storing a processing program; a processor for executing the method for on-orbit calibration of the emissivity of the geostationary orbit microwave radiometer antenna.

[0057] Based on the same concept, the present invention also provides a readable storage medium, on which a processing program is stored, and when the processing program is executed by a processor, the method for on-orbit calibration of the emissivity of the geostationary orbit microwave radiometer antenna is implemented.

[0058] When the on-orbit calibration method for the emissivity of the antenna of a geostationary orbit microwave radiometer is implemented in the form of program instructions and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this embodiment, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of software. This computer software is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present disclosure. The aforementioned storage medium includes: various media such as USB flash drives, external hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0059] Those skilled in the art can clearly understand that for the sake of convenient and concise description, the specific identification content executed by the above-described system and device can refer to the corresponding process in the foregoing method embodiments.

[0060] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, provided that these changes fall within the scope of the claims of the present invention and their equivalent technologies, they still fall within the protection scope of the present invention.

Claims

1. A method for on-orbit calibration of the emissivity of a geostationary orbit microwave radiometer antenna, characterized in that, Including: Calculating the antenna cascaded reflector transfer equation according to the transfer equations of the three reflectors of the microwave radiometer antenna; Obtain the microwave loss of the antenna cascaded link according to the two-point calibration equation of the feeding aperture plane and the antenna cascaded reflector transmission equation Equation; Adopt an antenna temperature control system to control the temperature gradients of the three reflecting surfaces of the antenna to the target values simultaneously at the same moment, and use the temperature control system to obtain the line-level cascade losses corresponding to the temperature states of the two sets of antenna reflecting surfaces Based on the microwave loss of the antenna cascade link According to the equation of the antenna cascade link microwave loss and the spectral power density formula corresponding to the physical temperature, calculate the relationship parameters between the surface reflectivity and the working surface temperature of the three reflecting surfaces of the antenna 2. The on-orbit calibration method for the emissivity of a geostationary orbit microwave radiometer antenna according to claim 1, characterized in that, The calculating the antenna cascaded reflector transfer equation according to the transfer equations of the three reflectors of the microwave radiometer antenna includes: The main reflector transmission equation is as follows: Wherein, is the average spectral power density output by the main reflector of the antenna, is the average spectral power density of the forward input of the main reflector of the antenna, is the average spectral power density of the backward input of the main reflector, is the spectral power density corresponding to the physical temperature of the main reflector, η1 is the forward radiation efficiency of the main reflector of the antenna, η2 is the forward radiation efficiency of the first sub-reflector, and ρ1 is the reflectivity of the main reflector of the antenna; The transmission equation of the first sub-reflector is as follows: Among them, the above formula is the average spectral power density output by the first sub-reflector of the antenna, is the average spectral power density of the backward input of the first sub-reflector, the spectral power density corresponding to the physical temperature of the first sub-reflector, η3 is the forward radiation efficiency of the second sub-reflector, and ρ2 is the reflectivity of the first sub-reflector; The transmission equation of the second sub-reflector is as follows: Wherein, is the average spectral power density of the output of the second sub-reflector of the antenna, is the average spectral power density of the backward input of the second sub-reflector, is the spectral power density corresponding to the physical temperature of the second sub-reflector, and ρ2 is the reflectivity of the second sub-reflector; Substituting the main reflector transfer equation into the first sub-reflector transfer equation, and then substituting the first sub-reflector transfer equation into the second sub-reflector transfer equation, to obtain the antenna cascaded reflector transfer equation as:

3. The on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna according to claim 2, wherein Ignoring the influence of the input average spectral power density of the antenna main reflector, the first sub-reflector and the second sub-reflector, simplifying the antenna cascaded reflector transfer equation to:

4. The on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna according to claim 3, wherein Obtain the microwave loss of the antenna cascaded link according to the two-point calibration equation of the feeding aperture plane and the antenna cascaded reflector transmission equation The equations include: The two-point calibration equation of the feed port surface is: Among them, represents the spectral power density of the thermal calibration source radiation, is the spectral power density of the cold sky, and the brightness temperature of the cold sky background radiation is Tc = 2.73 K, Spectral power density corresponding to the physical temperature of the cold sky mirror C S is the output count of the feed aperture observation antenna, C W is the output count of the feed aperture observation of the on-board heat source, C C is the output count of the feed aperture observation of the on-board heat source, ρ C is the reflectivity of the cold sky mirror. This value is accurately obtained by comparing the output counts of the feed aperture observing the vacuum cryogenic variable temperature source and the cold sky mirror observing the vacuum cryogenic variable temperature source in the ground vacuum calibration test. C value, η C Accurate ground test of the forward radiation efficiency of the cold sky mirror; Microwave Loss of Antenna Cascade Link The equation is as follows:

5. The on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna according to claim 4, wherein, Microwave Loss Based on Antenna Cascade Link Based on the equation and the spectral power density formula corresponding to the physical temperature, the parameters of the function relationship between the surface reflectivity of the three reflecting surfaces of the antenna and the operating surface temperature are calculated, including: The surface reflectivities of the three reflectors of the antenna and the working surface temperature have the same linear function as: where a and b are the constant term coefficient and the first-order term coefficient of the linear function of the antenna surface reflectivity and temperature respectively, represents the physical temperature of the main reflector, represents the physical temperature of the first sub-reflector, represents the physical temperature of the second sub-reflector; Substitute the linear function of the surface reflectivity and the operating surface temperature of the three reflecting surfaces of the antenna into the microwave loss of the antenna cascade link Equation to obtain: Among them, the spectral power densities corresponding to the physical temperatures of the main reflector, the first sub-reflector, and the second sub-reflector of the antenna are respectively: Among them, h is Planck's constant, with a value of 6.63×10 -34 J·s, f is the frequency, with the unit Hz, k is the Boltzmann constant, which is 1.38×10 -23 J·K -1 ; Based on the adoption of an antenna temperature control system, the temperature gradients of the three reflecting surfaces of the antenna are simultaneously controlled to the target values at the same moment. The temperature control system is used to obtain the line-level cascade losses corresponding to the temperature states of the two sets of antenna reflecting surfaces. Calculate the coefficients a and b to obtain the functional relationship between the surface reflectivity and the operating surface temperature of the three reflecting surfaces of the antenna, and then correct the self-radiation of the antenna.

6. A on-orbit calibration system for the emissivity of a geostationary orbit microwave radiometer antenna, characterized in that, Including: A cascaded reflection calculation module, configured to calculate the antenna cascaded reflector transfer equation according to the transfer equations of the three reflectors of the microwave radiometer antenna; A microwave loss calculation module, which is used to obtain the microwave loss of the antenna cascaded link according to the two-point calibration equation of the feed port surface and the antenna cascaded reflector transmission equation Equation; The parameter calculation module is used to adopt the antenna temperature control system to control the temperature gradients of the three reflector surfaces of the antenna to the target values at the same time, and use the temperature control system to obtain the line-level cascade loss corresponding to the temperature states of the two sets of antenna reflector surfaces. Based on the microwave loss of the antenna cascade link Equation and the physical temperature corresponding spectral power density formula, calculate the relationship parameters between the surface reflectivity and the working surface temperature function of the three reflector surfaces of the antenna.

7. An electronic device, characterized in that, Including: A memory for storing a processing program; A processor, when the processor executes the processing program, implementing the on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna as described in any one of claims 1 to 5.

8. A readable storage medium, characterized in that, A processing program is stored on the readable storage medium, and when the processing program is executed by the processor, implementing the on-orbit calibration method for the emissivity of the geostationary orbit microwave radiometer antenna as described in any one of claims 1 to 5.

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