Method for acquiring horizontal propagation phase velocity of gravity wave based on networking of three same-series low-light satellites

Abstract

The invention belongs to the field of remote sensing technology analysis, and particularly relates to a method for acquiring the horizontal propagation phase velocity of gravity waves based on networking of three same-series low-light satellites. Comprising the steps that S1, night low-light data of three satellites are acquired, and the night low-light data comprise SVDNB and GDNBO; s2, preprocessing the night low-light data, and extracting gravity wave stripes in a night low-light image; s3, the gravity wave fringes are corrected through a parallax correction model, the corrected gravity wave fringes are drawn together for pairing, and the corresponding relationship of gravity wave propagation is obtained; and S4, extracting the spacing distance between the gravitational wave stripes, and further calculating the horizontal propagation phase velocity of the gravitational wave. According to the method, satellites for acquiring the low-light data are increased from NPP to NPP, JPSS-1 and JPSS-2, and the time resolution of the polar orbit satellite night low-light data is improved; a parallax correction method of the gravity wave position is provided, and after the position of the gravitational wave stripe after geometric correction is extracted for parallax correction, the horizontal propagation phase velocity of the gravity wave is calculated.

Description

Technical Field

[0001] The invention belongs to the field of remote sensing technology analysis, and specifically relates to a method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series. Background Art

[0002] The Visible / Infrared Radiometric Imager (VIIRS) can detect the radiance information of the light on the earth's surface at night, and then form light data to be transmitted back to the ground via satellite. In the past two decades, nighttime low-light detection sensors have been put into orbit one after another, and the research and application technology related to such light data has also developed rapidly. The S-NPP (Suomi-National Polar-orbiting Partnership) satellite launched by the United States in 2011 carries the VIIRS (Visible Infrared Imaging Radiometer Suite) / DNB (Day Night Band), a low-light payload with powerful nighttime detection capabilities. The satellite-borne low-light imager is originally used to image the atmosphere and ground environment under low-light conditions at night. Miller et al. (2012) first discovered that the existence of gravity waves at the mesosphere usually causes the airglow radiation near it to present obvious streak image characteristics, which provides a new method for the observation of gravity waves at the mesosphere. At present, the satellite-borne low-light imager is ushering in an era of accelerated development, and satellite low-light data are gradually becoming abundant. Following S-NPP, the United States launched JPSS-1 and JPSS-2 satellites carrying the same type of low-light payloads in November 2017 and 2022. The three satellites operate in the same orbit, which significantly improves the temporal resolution of low-light observation data. Three gravity wave observations will be carried out in about 50 minutes, and the gravity wave propagation phase velocity parameters can be extracted more accurately. The SDR dataset developed based on VIIRS observation data from S-NPP, JPSS-1 and JPSS-2 satellites can provide daily nighttime satellite light data. This product is publicly released by NOAA at:

[0003] https: / / www.aev.class.noaa.gov / saa / products / search?sub_id=0&datatype_family=VIIRS_SDR&submit.x=20&submit.y=5. This paper mainly uses the SVDNB and GDNBO products consisting of 3072×4064 pixels in the SDR dataset. Among them, the SVDNB product provides the entrance pupil radiance that has been calibrated for operational radiometric calibration; the GDNBO product provides observation geometry information such as the latitude and longitude corresponding to the entrance pupil radiance and the satellite zenith angle.

[0004] In the prior art, no research has been found that networks the low-light data observed by three satellites and uses them to calculate the horizontal propagation phase velocity of mesotope gravity waves. Therefore, this application proposes a method for obtaining the horizontal propagation phase velocity of gravity waves based on networking three low-light satellites of the same series. Summary of the invention

[0005] In view of the above-mentioned problems, the purpose of the present invention is to fill the gap in the prior art in calculating the horizontal propagation phase velocity of gravity waves using satellite low-light data, and to provide a method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three low-light satellites of the same series. The method can obtain the horizontal propagation phase velocity of gravity waves at the mesosphere based on nighttime low-light data.

[0006] In order to achieve the above technical effects and the above objectives, the present invention provides a method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series, comprising:

[0007] S1: Obtain nighttime low-light data from three satellites, including SVDNB and GDNBO;

[0008] S2: Preprocess the nighttime low-light data and extract gravity wave stripes from the preprocessed nighttime low-light images;

[0009] S3: Correcting the extracted gravity wave stripes through a parallax correction model, drawing the corrected gravity wave stripes together for pairing, and obtaining the corresponding relationship of the gravity wave stripes;

[0010] S4: Based on the corresponding relationship of gravity wave fringes in S3, the interval distance between gravity wave fringes is extracted, and then the horizontal propagation phase velocity of gravity waves is calculated.

[0011] Preferably, the nighttime low light data preprocessing of S2 includes:

[0012] S2.1: Based on SVDNB, obtain the entrance pupil radiance;

[0013] S2.2: Based on GDNBO, obtain the observation geometry information of the longitude and latitude corresponding to the entrance pupil radiance and the satellite zenith angle;

[0014] S2.3: Based on the geographic information contained in GDNBO, a GLT file is constructed in ENVI software, the entrance pupil radiance of S2.1 is geometrically corrected, and the geometrically corrected gravity wave fringes are extracted.

[0015] Preferably, the correction performed by the S3 parallax correction model includes:

[0016] S3.1: The height of the satellite from the surface is H; the radius of the earth is R; the height of the mesosphere where the gravity wave is located from the ground is h; the pixel resolution of the low-light image is d; O is the center of the earth; S is the satellite; A is the sub-satellite point position; W is the true position of the gravity wave; T is the corresponding position of the gravity wave on the surface; E is the observed position of the gravity wave in the low-light image, and the corresponding row number in the observed data is r E , the number of columns is c E ; The length of the arc ET is the distance deviation between the gravity wave at the observation position and the corresponding position on the surface;

[0017] The satellite zenith angle θ is known, then:

[0018] ∠OES=π-θ

[0019] ∠OES is the angle between the center of the Earth and the satellite, with the observation position of gravity waves in the low-light image as the vertex;

[0020] S3.2: In the ΔOES consisting of the Earth's center, the observed position of gravity waves in the low-light image, and the three satellite points, and the ΔOWS consisting of the Earth's center, the true position of gravity waves, and the three satellite points, the sine theorem yields:

[0021]

[0022]

[0023] so:

[0024] (R+H)sin∠OSE=Rsin(π-θ)

[0025]

[0026] Then ET is:

[0027] ET=R·∠WOE

[0028] Among them, ∠OSE is the angle formed by the center of the earth and the observed position of gravity waves in the low-light image, with the satellite as the vertex; ∠OWS is the angle formed by the center of the earth and the satellite, with the real position of gravity waves as the vertex; ∠WOE is the angle formed by the center of the earth as the vertex, the real position of gravity waves and the observed position of gravity waves in the low-light image;

[0029] S3.3: Based on S3.2, the number of pixels N of the deviation is,

[0030]

[0031] Where, d represents the pixel resolution of the low-light image;

[0032] S3.4: The number of rows r of gravity waves at the corresponding position T on the surface after processing by S3.1-S3.3 T and the number of columns c T They are:

[0033] r T =r E

[0034]

[0035] S3.5: The number of gravity waves at the corresponding position T on the surface obtained from S3.4: T and the number of columns c T , we can find the longitude and latitude of the corresponding position T of the gravity wave on the surface according to GDNBO.

[0036] Preferably, step 4 is specifically:

[0037] Based on the distance D between the longitude and latitude of the corresponding position T on the surface of the S3.5 gravity wave and the satellite scanning interval T, the horizontal propagation phase velocity is defined as V, then:

[0038]

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention uses a satellite data source different from the past. The number of satellites for obtaining low-light data has increased from NPP to NPP, JPSS-1 and JPSS-2, thereby improving the temporal resolution of low-light data of polar-orbiting satellites at night. A method for observing gravity waves based on a network of three polar-orbiting satellites in the same orbit is proposed. A parallax correction method for the position of gravity waves is proposed, and the position of gravity wave stripes after geometric correction is extracted for parallax correction, and then the horizontal propagation phase velocity of the gravity waves is calculated. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0042] In the attached picture:

[0043] Figure 1 A schematic diagram of a process flow of an embodiment of the present invention;

[0044] Figure 2 is a schematic diagram of a parallax correction model according to an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the position after gravity wave parallax correction according to an embodiment of the present invention;

[0046] Figure 4Schematic diagram of calculation of horizontal propagation phase velocity of gravity waves according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following is combined with Figure 1-4 The preferred embodiments of the present invention are described. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0048] Example:

[0049] A method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series, comprising:

[0050] S1: Obtain nighttime low-light data from three satellites, including SVDNB and GDNBO.

[0051] S2: Preprocess the nighttime low-light data and extract the gravity wave stripes in the preprocessed nighttime low-light image (under conditions of weak moonlight and no clouds, gravity waves will show light and dark stripes in the low-light image, and the clearly recognizable stripes will be depicted). S2's nighttime low-light data preprocessing includes:

[0052] S2.1: Based on SVDNB, obtain the entrance pupil radiance;

[0053] S2.2: Based on GDNBO, obtain the observation geometry information of the longitude and latitude corresponding to the entrance pupil radiance and the satellite zenith angle;

[0054] S2.3: Based on the geographic information contained in GDNBO, a GLT file is constructed in ENVI software, the entrance pupil radiance of S2.1 is geometrically corrected, and the geometrically corrected gravity wave fringes are extracted.

[0055] S3: Correcting the extracted gravity wave stripes through a parallax correction model, drawing the corrected gravity wave stripes together for pairing, and obtaining the corresponding relationship of the gravity wave stripes;

[0056] The schematic diagram of the parallax correction model of the embodiment of the present invention is as follows Figure 2 The schematic diagram of the position after gravity wave parallax correction is shown in Figure 3 The schematic diagram of gravity wave horizontal propagation phase velocity calculation is shown in Figure 4 As shown, it can be seen that the position of the gravity wave fringes has changed significantly after parallax correction.

[0057] The S3 parallax correction model performs corrections including:

[0058] S3.1: The height of the satellite from the surface is H; the radius of the earth is R; the height of the mesosphere where the gravity wave is located from the ground is h; the pixel resolution of the low-light image is d; O is the center of the earth; S is the satellite; A is the sub-satellite point position; W is the true position of the gravity wave; T is the corresponding position of the gravity wave on the surface; E is the observed position of the gravity wave in the low-light image, and the corresponding row number in the observed data is r E , the number of columns is c E ; The length of the arc ET is the distance deviation between the gravity wave at the observation position and the corresponding position on the surface;

[0059] The satellite zenith angle θ is known, then:

[0060] ∠OES=π-θ

[0061] ∠OES is the angle between the center of the Earth and the satellite, with the observation position of gravity waves in the low-light image as the vertex;

[0062] S3.2: In the ΔOES consisting of the Earth's center, the observed position of gravity waves in the low-light image, and the three satellite points, and the ΔOWS consisting of the Earth's center, the true position of gravity waves, and the three satellite points, the sine theorem yields:

[0063]

[0064] so:

[0065] (R+H)sin∠OSE=Rsin(π-θ)

[0066]

[0067] Then ET is:

[0068] ET=R·∠WOE

[0069] Among them, ∠OSE is the angle formed by the center of the earth and the observed position of gravity waves in the low-light image, with the satellite as the vertex; ∠OWS is the angle formed by the center of the earth and the satellite, with the real position of gravity waves as the vertex; ∠WOE is the angle formed by the center of the earth as the vertex, the real position of gravity waves and the observed position of gravity waves in the low-light image;

[0070] S3.3: Based on S3.2, the number of pixels N of the deviation is,

[0071]

[0072] Where, d represents the pixel resolution of the low-light image;

[0073] S3.4: The number of rows r of gravity waves at the corresponding position T on the surface after processing by S3.1-S3.3 T and the number of columns cT They are:

[0074] r T =r E

[0075]

[0076] S3.5: The number of gravity waves at the corresponding position T on the surface obtained from S3.4: T and the number of columns c T , we can find the longitude and latitude of the corresponding position T of the gravity wave on the surface according to GDNBO.

[0077] S4: Based on the corresponding relationship of gravity wave fringes in S3, extract the interval distance between gravity wave fringes, and then calculate the horizontal propagation phase velocity of gravity waves. Specifically:

[0078] Based on the distance D between the longitude and latitude of the corresponding position T on the surface of the S3.5 gravity wave and the satellite scanning interval T, the horizontal propagation phase velocity is defined as V, then:

[0079]

[0080] It can be seen from the invention content and embodiments that the present invention obtains nighttime low-light data through a visible light / infrared radiation imager, extracts the position of gravity wave stripes through geometric correction, obtains the real position of gravity waves through a parallax correction model, and thus studies the propagation process of gravity waves in the low-light images of three satellites; then extracts the corresponding distance in the stripes and calculates the horizontal propagation phase velocity of gravity waves, which makes up for the defect that the horizontal propagation phase velocity of gravity waves cannot be calculated through nighttime satellite light data.

[0081] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series, characterized by: include: S1: Obtain nighttime low-light data from three satellites, including SVDNB and GDNBO; S2: Preprocess the nighttime low-light data and extract gravity wave stripes from the preprocessed nighttime low-light images; S3: Correcting the extracted gravity wave stripes through a parallax correction model, drawing the corrected gravity wave stripes together for pairing, and obtaining the corresponding relationship of the gravity wave stripes; S4: Based on the corresponding relationship of gravity wave fringes in S3, the interval distance between gravity wave fringes is extracted, and then the horizontal propagation phase velocity of gravity waves is calculated.

2. According to claim 1, a method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series, characterized in that: S2 nighttime low-light data preprocessing includes: S2.1: Based on SVDNB, obtain the entrance pupil radiance; S2.2: Based on GDNBO, obtain the observation geometry information of the longitude and latitude corresponding to the entrance pupil radiance and the satellite zenith angle; S2.3: Based on the geographic information contained in GDNBO, a GLT file is constructed in ENVI software, the entrance pupil radiance of S2.1 is geometrically corrected, and the geometrically corrected gravity wave fringes are extracted.

3. The method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series according to claim 2, characterized in that: The S3 parallax correction model performs corrections including: S3.1: The height of the satellite from the surface is H; the radius of the earth is R; the height of the mesosphere where the gravity wave is located from the ground is h; the pixel resolution of the low-light image is d; O is the center of the earth; S is the satellite; A is the sub-satellite point position; W is the true position of the gravity wave; T is the corresponding position of the gravity wave on the surface; E is the observed position of the gravity wave in the low-light image, and the corresponding row number in the observed data is r E , the number of columns is c E ; The length of the arc ET is the distance deviation between the gravity wave at the observation position and the corresponding position on the surface; The satellite zenith angle θ is known, then: ∠OES=π-θ ∠OES is the angle between the center of the Earth and the satellite, with the observation position of gravity waves in the low-light image as the vertex; S3.2: In the ΔOES consisting of the Earth's center, the observed position of gravity waves in the low-light image, and the three satellite points, and the ΔOWS consisting of the Earth's center, the true position of gravity waves, and the three satellite points, the sine theorem yields: so: (R+H)sin∠OSE=Rsin(π-θ) Then ET is: ET=R·∠WOE Among them, ∠OSE is the angle formed by the center of the earth and the observed position of gravity waves in the low-light image, with the satellite as the vertex; ∠OWS is the angle formed by the center of the earth and the satellite, with the real position of gravity waves as the vertex; ∠WOE is the angle formed by the center of the earth as the vertex, the real position of gravity waves and the observed position of gravity waves in the low-light image; S3.3: Based on S3.2, the number of pixels N of the deviation is, Where, d represents the pixel resolution of the low-light image; S3.4: The number of rows r of gravity waves at the corresponding position T on the surface after processing by S3.1-S3.3 T and the number of columns c T They are: r T ＝r E S3.5: The number of gravity waves at the corresponding position T on the surface obtained from S3.4: T and the number of columns c T , we can find the longitude and latitude of the corresponding position T of the gravity wave on the surface according to GDNBO.

4. The method for obtaining the horizontal propagation phase velocity of gravity waves based on a network of three micro-light satellites of the same series according to claim 3, characterized in that: Step 4 is as follows: Based on the distance D between the longitude and latitude of the corresponding position T on the surface of the S3.5 gravity wave and the satellite scanning interval T, the horizontal propagation phase velocity is defined as V, then:

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