Method for remotely sensing and detecting horizontal wind field profile of atmosphere in intermediate layer of aventurine by using microwave limb radiometer

Abstract

The invention provides a method for remote sensing detection of a Jinstar intermediate layer atmosphere horizontal wind field profile by using a microwave limb radiometer, and the method comprises the steps: designing a detection channel of the Jinstar intermediate layer atmosphere horizontal wind field profile based on the characteristics of a Jinstar gas spectral line, obtaining radiation brightness temperature observation values of the detection channel at different tangent heights in two orthogonal directions through a microwave limb radiometer carried by a star orbiter; the characteristics of the golden star gas spectral lines are as follows: in a microwave frequency band, the golden star atmospheric trace gas spectral lines are rich and have obvious absorption peaks, and the high-speed atmospheric motion of the middle layer enables the gas absorption spectral lines to generate obvious Doppler frequency shift; and through physical iteration inversion, inversion is carried out based on the radiation brightness temperature observation value to obtain a golden star intermediate layer atmosphere horizontal wind field profile. The method has the advantages that back scattering and other intermediate processes are not needed, the method is basically not affected by ground surface high-temperature radiation, and continuous, stable, high-temporal-spatial-resolution and high-precision star intermediate layer atmosphere horizontal wind field profile information can be obtained all day long.

Description

Technical Field

[0001] The present application belongs to the field of microwave remote sensing, and specifically relates to a method for remotely sensing the horizontal wind field profile of the mesosphere of Venus using a microwave limb radiometer. Background Art

[0002] The complex atmospheric circulation in the 60-110km mesosphere of Venus is a hot spot for Venus exploration and research. The detection results of past Venus missions show that the circulation in this area is mainly a global atmospheric circulation from east to west along the equal latitude circle. At the top of the cloud layer of Venus (about 65km in altitude), the horizontal wind speed in the east-west direction can reach up to 120m / s, which is nearly 60 times faster than its surface rotation (243 Earth days). This phenomenon is called "super rotation". In addition to super rotation, the north-south circulation of the mesosphere is also very significant. At an altitude of 90-100km, the horizontal wind speed in the north-south direction can reach 100m / s. At the poles of Venus, the mesosphere also has a double eye structure and a huge vortex. Compared with the relatively stable lower atmosphere (below 60km), the diurnal variation of the wind in the mesosphere of Venus is large, and there are obvious differences between the day and night hemispheres and the equator and the polar regions, which brings great challenges to detection.

[0003] Existing remote sensing missions for the atmosphere of Venus mainly use visible light, infrared to ultraviolet spectrum remote sensing methods to obtain continuously observed cloud images, using clouds (distributed at 40-70km) as tracers to obtain atmospheric motion information. However, due to the reliance on clouds as tracers and the great atmospheric optical attenuation caused by dense sulfuric acid clouds, the main horizontal wind data obtained were near the cloud tops in the dayside hemisphere of Venus (65-70km). The existing detection data cannot fully describe the vertical profile and temporal and spatial variation information of the atmospheric wind of Venus, resulting in great uncertainty in the currently established atmospheric circulation model of Venus, which restricts human understanding of the causes and maintenance mechanisms of dynamic phenomena such as Venus' superrotation. Summary of the invention

[0004] In response to the current gaps in the detection of the horizontal wind field profile in the mesosphere of Venus, this application provides a method for remotely detecting the horizontal wind field profile in the mesosphere of Venus using a microwave limb radiometer, with the aim of achieving global continuous, high temporal and spatial resolution, and high-precision observation of the horizontal wind field profile in the mesosphere of Venus.

[0005] In order to achieve the above-mentioned purpose, the present application proposes a method for remotely sensing the horizontal wind field profile of the mesosphere of Venus using a microwave limb radiometer, comprising:

[0006] Step S1) designing a detection channel for the horizontal wind field profile of the mesosphere atmosphere of Venus based on the characteristics of the gas spectrum line of Venus, and obtaining radiation brightness temperature observation values ​​of the detection channel at different cut heights in two orthogonal directions by a microwave limb radiometer carried by the Venus orbiter; the characteristics of the gas spectrum line of Venus are: in the microwave frequency band, the spectrum lines of trace gases in the atmosphere of Venus are rich and have obvious absorption peaks, and the high-speed atmospheric motion in the mesosphere causes a significant Doppler frequency shift in the gas absorption spectrum line;

[0007] Step S2) Inverting the horizontal wind field profile of the middle atmosphere of Venus based on the radiation brightness temperature observation value through physical iterative inversion.

[0008] As an improvement of the above method, the middle atmosphere of Venus in step S1) includes an atmosphere with an altitude range of 60-110 km.

[0009] As an improvement of the above method, the design of the detection channel of the horizontal wind field profile of the middle atmosphere of Venus in step S1) includes:

[0010] Step S1A-1) The microwave limb radiometer adopts a double-sideband receiver system, the receiver bandwidth is 1-5 GHz, and the receiver spectrum resolution is 500 KHz-5 MHz;

[0011] Step S1A-2) using the Venus atmospheric profile data, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory to obtain brightness temperatures at different limb tangent heights in the range of 60-110 km;

[0012] Step S1A-3) According to the spectral characteristics of brightness temperature, gas spectral lines with strong absorption peaks and spectral line center frequency intervals greater than the receiver spectral resolution are selected as candidate target spectral lines;

[0013] Step S1A-4) According to the position of the candidate target spectral line and the bandwidth of the receiver, the channel planning of the upper and lower sidebands is performed respectively, so as to cover as many strong absorption spectral lines as possible within the bandwidth to obtain high Doppler frequency shift signal detection capability;

[0014] Step S1A-5) Using the Venus atmospheric profile data, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory, and the influence of the upper and lower sideband aliasing effect on the brightness temperature spectrum characteristics is analyzed. If the spectral line absorption peak disappears due to the aliasing of the double sideband, the upper and lower sideband schemes are adjusted while ensuring the coverage of the strong absorption spectral line until the target spectral line absorption peak is still visible after the double sideband aliasing;

[0015] Step S1A-6) uses the Venus atmospheric profile data to simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory to obtain the sensitivity of the initially designed channel to changes in wind speed at different altitudes, that is, the changes in brightness temperature of each channel of the microwave limb radiometer caused by wind at different tangent altitudes. If the brightness temperature changes at each tangent altitude are less than the system sensitivity of the radiometer, the channel plan is adjusted and steps S1A-4) to S1A-6) are repeated until the brightness temperature changes at each tangent altitude of 60-110 km are greater than the sensitivity of the radiometer, thereby obtaining the final channel plan.

[0016] As an improvement of the above method, the microwave limb radiometer carried by the Venus orbiter in step S1) has a pair of vertically orthogonal antennas or antennas with the ability to rotate; the antenna has the ability to sweep up and down.

[0017] As an improvement of the above method, the step S1) obtains the radiation brightness temperature observation values ​​of the detection channel at different cut heights in two orthogonal directions by using the microwave limb radiometer carried by the Venus orbiter, including:

[0018] Step S1B-1) If the microwave limb radiometer has a pair of vertically orthogonal antennas, the two antennas are used to sweep up and down to observe the atmosphere in the altitude range of 60-110 km layer by layer; if the microwave limb radiometer has a rotatable antenna, the antenna is first swept up and down in one direction to observe the atmosphere in the altitude range of 60-110 km layer by layer, and then the antenna is rotated 90 degrees and the antenna is swept up and down again to observe the atmosphere in the altitude range of 60-110 km layer by layer again;

[0019] Step S1B-2) Through the calibration algorithm and in combination with the antenna radiation pattern, the electrical signals received by each channel of the microwave limb radiometer during the scanning process are converted into radiation brightness temperature observation values, and the observation values ​​of the two antennas or two vertical directions are combined to obtain the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions.

[0020] As an improvement of the above method, the physical iterative inversion in step S2) includes:

[0021] Step S2-1) using the initial estimated values ​​of the horizontal wind speed profiles of the mesosphere of Venus in two orthogonal directions, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory, and initial simulated values ​​of the radiation brightness temperature of each detection channel at different cut heights in the two orthogonal directions are simulated respectively;

[0022] Step S2-2) constructs a cost function based on the Tikhonov regularization method, and substitutes the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions and the corresponding initial simulation values ​​of the radiation brightness temperature into the following cost function J(X):

[0023]

[0024] Here, the operator ||A|| B Indicates A T BA, T represents matrix transposition; X represents the inversion parameter, i.e., the horizontal wind speed profile of the middle atmosphere of Venus; F(X) represents the simulated value of radiation brightness temperature; Y m Observed radiation brightness temperature; S o represents the measurement error covariance matrix; S a represents the background field error covariance matrix; X 0 represents the initial estimate of the horizontal wind speed profile in the mesosphere of Venus; λ represents the regularization parameter.

[0025] Step S2-3) by solving the minimum value of the cost function, the Newton iteration method is used to iteratively solve the vertical distribution of atmospheric wind speed in two orthogonal directions; in the iterative inversion, the first-order derivative matrix is ​​used as the regularization matrix, and the initial regularization parameter uses the singular value decomposition result of the partial derivative matrix based on the inversion target parameter. In the process of iterative inversion of the atmospheric wind profile, the L curve method is used to optimize the selection of the regularization parameter λ;

[0026] Step S2-4) Combine the vertical distribution inversion results of atmospheric wind speed in two orthogonal directions to obtain the horizontal wind field profile of the middle layer of Venus.

[0027] Compared with the prior art, the advantages of this application are:

[0028] The method of the present invention can obtain continuous, stable, high-temporal and spatial resolution, high-precision horizontal wind field profile information of the mesosphere of Venus all day long. The present invention uses the microwave limb radiometer carried by the Venus orbiter to obtain the horizontal wind field profile information of the mesosphere of Venus. Since the detection of the microwave limb radiometer does not rely on light sources and tracer clouds, does not require intermediate processes such as backscattering, and is basically not affected by the high temperature (470°C) radiation of the surface, it has unique advantages in the detection of the mesosphere of Venus. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Shown is a flow chart of a method for remotely sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer. DETAILED DESCRIPTION

[0030] The technical solution of the present application is described in detail below with reference to the accompanying drawings.

[0031] In view of the lack of existing remote sensing detection methods for the horizontal wind field profile of the mesosphere of Venus, the present invention provides a method for remote sensing detection of the horizontal wind field profile of the mesosphere of Venus using a microwave limb radiometer, which can realize global continuous detection of the horizontal wind profile of the mesosphere of Venus and its temporal and spatial variation information.

[0032] like Figure 1 As shown, the present invention provides a method for remotely sensing the horizontal wind field profile of the middle layer of the atmosphere of Venus using a microwave limb radiometer, comprising:

[0033] Step 1: In the microwave frequency band, the spectral lines of trace gases in the Venusian atmosphere are very rich and have very obvious absorption peaks. The high-speed atmospheric motion in the mesosphere will cause a significant Doppler shift in the gas absorption spectral lines. Based on this characteristic, the microwave limb radiometer is used to detect the Doppler shift of the trace gas spectral lines to detect the horizontal wind field profile of the mesosphere atmosphere of Venus;

[0034] Step 2: According to the application requirements and the detection principle obtained in step 1, determine the remote sensing detection scheme of the horizontal wind field profile of the Venus mesosphere using the microwave limb radiometer.

[0035] This step further includes the following processing method:

[0036] According to the detection principle obtained in step 1, the required microwave radiometer should be carried on the Venus orbiter to carry out remote sensing detection of the horizontal wind profile of the Venus mesosphere atmosphere. The orbit of the Venus orbiter should adopt a low Venus circular orbit as much as possible.

[0037] According to the detection principle obtained in step 1, in order to obtain wind field (including wind speed and wind direction) information, the required microwave limb radiometer should have a pair of vertically orthogonal antennas or the antenna should have the ability to rotate, and the antenna should have the ability to swing up and down;

[0038] According to the detection principle obtained in step 1, the required microwave limb radiometer scanning mode is limb scanning, and the radiation brightness temperature observation value is obtained at the top of the atmosphere;

[0039] According to the application requirements of the horizontal wind field profile data of the Venus mesosphere, combined with the detection capabilities of the Venus orbiter, and considering the constraints of deep space exploration on the volume and weight of the instrument, the system design of the microwave radiometer is carried out to determine various system parameters, such as antenna aperture, antenna gain, radiation sensitivity, integration time, etc.

[0040] Step 3: Based on the detection principle of the horizontal wind field profile of the mesosphere of Venus obtained in step 1, it is necessary to obtain the fine vertical profile of the horizontal wind field in the 60-110km altitude range of the mesosphere of Venus by measuring the Doppler frequency shift of the strong absorption spectrum line, and design the detection channel of the horizontal wind field profile of the mesosphere of Venus according to this principle;

[0041] This step further includes the following processing method:

[0042] Step 3-1: In order to cover more gas spectral lines, the microwave limb radiometer adopts a double-sideband receiver system. Considering the maturity and complexity of the instrument, the receiver bandwidth is designed to be in the range of 1-5GHz, and the spectrum resolution is designed to be in the range of 500KHz-5MHz;

[0043] Step 3-2: Using the Venus atmospheric profile data, simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory to obtain the brightness temperature at different limb tangent heights (60-110km);

[0044] Step 3-3: According to the spectral characteristics of brightness temperature, select gas spectral lines with strong absorption peaks and spectral line center frequency intervals greater than the receiver spectral resolution as candidate target spectral lines;

[0045] Step 3-4: According to the position of the candidate target spectral line and the bandwidth of the receiver, the channel planning of the upper and lower sidebands is carried out respectively, so as to cover as many strong absorption spectral lines as possible within the bandwidth to obtain high Doppler frequency shift signal detection capability;

[0046] Step 3-5: Use the Venus atmospheric profile data to simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory, and analyze the impact of the upper and lower sideband aliasing effect on the brightness temperature spectrum characteristics. If the aliasing of the double sideband will cause the disappearance of the spectral line absorption peak, adjust the upper and lower sideband schemes while ensuring the coverage of the strong absorption spectrum line until the target spectral line absorption peak is still clearly visible after the double sideband aliasing;

[0047] Step 3-6: Using the atmospheric profile data of Venus, simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory to obtain the sensitivity of the initially designed channel to the wind speed changes at different altitudes, that is, the changes in the brightness temperature of each channel of the microwave limb radiometer caused by the wind at different tangent altitudes. If the brightness temperature changes at each tangent altitude are less than the system sensitivity of the radiometer, adjust the channel plan and repeat steps 3-4 to 3-6 until the brightness temperature changes at each tangent altitude of 60-110 km are greater than the sensitivity of the radiometer, and obtain the final channel plan.

[0048] Step 4: According to the system parameter scheme obtained in step 2 and the channel scheme obtained in step 3, the microwave limb radiometer is developed and loaded on the Venus orbiter, the Venus orbiter is launched, and the Earth-Venus orbit transfer is completed to the Venus orbiter orbit;

[0049] Step 5: Obtain the radiation brightness temperature observation values ​​of the detection channels at different cut heights in two orthogonal directions through the microwave limb radiometer carried by the Venus orbiter;

[0050] This step further includes the following processing method:

[0051] Step 5-1: If the microwave limb radiometer has a pair of vertically orthogonal antennas, the two antennas are swept up and down to observe the atmosphere layer by layer in the altitude range of 60-110 km; if the microwave limb radiometer has a rotating antenna, the antenna is first swept up and down in one direction to observe the atmosphere layer by layer in the altitude range of 60-110 km, and then the antenna is rotated 90 degrees and swept up and down again to observe the atmosphere layer by layer in the altitude range of 60-110 km again.

[0052] Step 5-2: Through the calibration algorithm and in combination with the antenna pattern, the electrical signals received by each channel of the microwave limb radiometer during the scanning process are converted into radiation brightness temperature observation values. By combining the observations of two antennas or two vertical directions, the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions are obtained;

[0053] Step 6: Establish a physical iterative inversion algorithm to invert the horizontal wind field profile of the middle atmosphere of Venus from the radiation brightness temperature observation value obtained in step 5.

[0054] This step further includes the following processing method:

[0055] Step 6-1: Using the initial estimated values ​​of the horizontal wind speed profiles of the mesosphere of Venus in two orthogonal directions, simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory, and simulate and obtain the initial simulated values ​​of the radiation brightness temperature of each detection channel at different cut heights in the two orthogonal directions;

[0056] Step 6-2: Construct a cost function based on the Tikhonov regularization method, and substitute the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions and the corresponding initial simulation values ​​of radiation brightness temperature into the following cost function J(X):

[0057]

[0058] Among them, ||A|| B =A T BA, X represents the inversion parameter, i.e., the horizontal wind speed profile of the middle atmosphere of Venus, F(X) represents the simulated value of the radiation brightness temperature, Y m Observed radiation brightness temperature, S o represents the measurement error covariance matrix, S a represents the background field error covariance matrix, X 0 represents the initial estimate of the horizontal wind speed profile in the middle atmosphere of Venus, λ represents the regularization parameter; T represents the matrix transpose.

[0059] Step 6-3: By solving the minimum value of the cost function, the vertical distribution of atmospheric wind speed in two orthogonal directions is iteratively solved according to the Newton iteration method. In the iterative inversion, the first-order derivative matrix is ​​used as the regularization matrix, and the initial regularization parameter uses the singular value decomposition result of the partial derivative matrix based on the inversion target parameter. In the iterative inversion process of the atmospheric wind profile, the L curve method is used to optimize the selection of the regularization parameter λ.

[0060] Step 6-4: Combine the inversion results of the vertical distribution of atmospheric wind speed in two orthogonal directions to obtain the horizontal wind field profile of the mesosphere of Venus.

[0061] In summary, the present application provides a method for remotely sensing the horizontal wind field profile of the mesosphere of Venus using a microwave limb radiometer, which uses a microwave limb radiometer to detect the Doppler frequency shift of trace gas spectral lines to obtain the horizontal wind field profile information of the mesosphere of Venus.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application is described in detail with reference to the embodiments, a person skilled in the art should understand that any modification or equivalent replacement of the technical solution of the present application does not depart from the spirit and scope of the technical solution of the present application and should be included in the scope of the claims of the present application.

Claims

1. A method for remotely sensing the horizontal wind field profile of the mesosphere of Venus using a microwave limb radiometer, comprising: Step S1) designing a detection channel for the horizontal wind field profile of the mesosphere atmosphere of Venus based on the characteristics of the gas spectrum line of Venus, and obtaining radiation brightness temperature observation values ​​of the detection channel at different cut heights in two orthogonal directions by a microwave limb radiometer carried by the Venus orbiter; the characteristics of the gas spectrum line of Venus are: in the microwave frequency band, the spectrum lines of trace gases in the atmosphere of Venus are rich and have obvious absorption peaks, and the high-speed atmospheric motion in the mesosphere causes a significant Doppler frequency shift in the gas absorption spectrum line; Step S2) Inverting the horizontal wind field profile of the middle atmosphere of Venus based on the radiation brightness temperature observation value through physical iterative inversion.

2. The method for remote sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer according to claim 1, characterized in that: The Venus mesosphere in step S1) includes an atmosphere with an altitude ranging from 60 to 110 km.

3. The method for remote sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer according to claim 1, characterized in that: The design of the detection channel for the horizontal wind field profile of the Venus mesosphere atmosphere in step S1) includes: Step S1A-1) The microwave limb radiometer adopts a double-sideband receiver system, the receiver bandwidth is 1-5 GHz, and the receiver spectrum resolution is 500 KHz-5 MHz; Step S1A-2) using the Venus atmospheric profile data, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory to obtain brightness temperatures at different limb tangent heights in the range of 60-110 km; Step S1A-3) According to the spectral characteristics of brightness temperature, gas spectral lines with strong absorption peaks and spectral line center frequency intervals greater than the receiver spectral resolution are selected as candidate target spectral lines; Step S1A-4) According to the position of the candidate target spectral line and the bandwidth of the receiver, the channel planning of the upper and lower sidebands is performed respectively, so as to cover as many strong absorption spectral lines as possible within the bandwidth to obtain high Doppler frequency shift signal detection capability; Step S1A-5) Using the Venus atmospheric profile data, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory, and the influence of the upper and lower sideband aliasing effect on the brightness temperature spectrum characteristics is analyzed. If the spectral line absorption peak disappears due to the aliasing of the double sideband, the upper and lower sideband schemes are adjusted while ensuring the coverage of the strong absorption spectral line until the target spectral line absorption peak is still visible after the double sideband aliasing; Step S1A-6) uses the Venus atmospheric profile data to simulate the brightness temperature of the limb radiometer according to the planetary atmospheric radiation transfer theory to obtain the sensitivity of the initially designed channel to changes in wind speed at different altitudes, that is, the changes in brightness temperature of each channel of the microwave limb radiometer caused by wind at different tangent altitudes. If the brightness temperature changes at each tangent altitude are less than the system sensitivity of the radiometer, the channel plan is adjusted and steps S1A-4) to S1A-6) are repeated until the brightness temperature changes at each tangent altitude of 60-110 km are greater than the sensitivity of the radiometer, thereby obtaining the final channel plan.

4. The method for remote sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer according to claim 1, characterized in that: The microwave limb radiometer carried by the Venus orbiter in step S1) has a pair of vertically orthogonal antennas or antennas with rotation capability; the antennas have the capability of sweeping up and down.

5. The method for remote sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer according to claim 1, characterized in that: The step S1) of obtaining the radiation brightness temperature observation values ​​of the detection channel at different cut heights in two orthogonal directions by the microwave limb radiometer carried by the Venus orbiter includes: Step S1B-1) If the microwave limb radiometer has a pair of vertically orthogonal antennas, the two antennas are used to sweep up and down to observe the atmosphere in the altitude range of 60-110 km layer by layer; if the microwave limb radiometer has a rotatable antenna, the antenna is first swept up and down in one direction to observe the atmosphere in the altitude range of 60-110 km layer by layer, and then the antenna is rotated 90 degrees and the antenna is swept up and down again to observe the atmosphere in the altitude range of 60-110 km layer by layer again; Step S1B-2) Through the calibration algorithm and in combination with the antenna radiation pattern, the electrical signals received by each channel of the microwave limb radiometer during the scanning process are converted into radiation brightness temperature observation values, and the observation values ​​of the two antennas or two vertical directions are combined to obtain the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions.

6. The method for remote sensing the horizontal wind field profile of the middle atmosphere of Venus using a microwave limb radiometer according to claim 1, characterized in that: The physical iterative inversion of step S2) comprises: Step S2-1) using the initial estimated values ​​of the horizontal wind speed profiles of the mesosphere of Venus in two orthogonal directions, limb radiometer brightness temperature simulation is performed according to the planetary atmospheric radiation transfer theory, and initial simulated values ​​of the radiation brightness temperature of each detection channel at different cut heights in the two orthogonal directions are simulated respectively; Step S2-2) constructs a cost function based on the Tikhonov regularization method, and substitutes the radiation brightness temperature observation values ​​of each detection channel at different cut heights in two orthogonal directions and the corresponding initial simulation values ​​of the radiation brightness temperature into the following cost function J(X): Among them, the operator ||A|| B Indicates A T BA, T represents matrix transposition; X represents the inversion parameter, i.e., the horizontal wind speed profile of the middle atmosphere of Venus; F(X) represents the simulated value of radiation brightness temperature; Y m Observed radiation brightness temperature; S o represents the measurement error covariance matrix; S a represents the background field error covariance matrix; X0 represents the initial estimate of the horizontal wind speed profile of the middle atmosphere of Venus; λ represents the regularization parameter; Step S2-3) by solving the minimum value of the cost function, the Newton iteration method is used to iteratively solve the vertical distribution of atmospheric wind speed in two orthogonal directions; in the iterative inversion, the first-order derivative matrix is ​​used as the regularization matrix, and the initial regularization parameter uses the singular value decomposition result of the partial derivative matrix based on the inversion target parameter. In the process of iterative inversion of the atmospheric wind profile, the L curve method is used to optimize the selection of the regularization parameter λ; Step S2-4) Combine the inversion results of the vertical distribution of atmospheric wind speed in two orthogonal directions to obtain the horizontal wind field profile of the middle layer of Venus.

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