Calibration equipment, measurement unit, and method for calibrating a measuring device

Abstract

Calibration equipment is easily installed. [Solution] The calibration equipment includes a first stand on which a calibration tool filled with liquid nitrogen is placed, the first stand including a plurality of receiving portions, and the first stand is removably supported at the plurality of receiving portions by a plurality of supports arranged around the measuring device to be calibrated.

Description

[Technical Field]

[0001] The present disclosure relates to a calibration instrument, a measurement unit, and a method for calibrating a measurement device. [Background technology]

[0002] Conventionally, there are known techniques for calibrating microwave radiometers that observe the amount of water vapor in the atmosphere. For example, see MP-3000A and HATPRO Calibration Comparison, [Retrieved August 27, 2024], Internet, <https: / / radiometrics.com / wp-content / uploads / 2022 / 04 / MP-3000A_and_HATPRO_Calibration_Comparison_160101.pdf> Non-Patent Document 1 discloses a technique for calibrating a microwave radiometer using a container filled with liquid nitrogen. [Prior art documents] [Patent documents]

[0003] [Non-Patent Document 1] MP-3000A and HATPRO Calibration Comparison, [Retrieved August 27, 2024], Internet, <https: / / radiometrics.com / wp-content / uploads / 2022 / 04 / MP-3000A_and_HATPRO_Calibration_Comparison_160101.pdf> Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when calibrating a microwave radiometer, a calibration tool filled with liquid nitrogen is installed around the microwave radiometer. In some cases, multiple supports are installed around the microwave radiometer, for example, to keep birds away. In such cases, a technique is needed that allows the calibration tool to be easily installed.

[0005] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide a calibration instrument, a measurement unit, and a method for calibrating a measurement device that allow calibration equipment to be easily installed. [Means for solving the problem]

[0006] (1) A calibration device according to an embodiment of the present disclosure includes a first stand on which a calibration tool filled with liquid nitrogen is placed, the first stand including a plurality of receiving portions, and the first stand being removably supported at the plurality of receiving portions by a plurality of supports provided around the measuring device to be calibrated.

[0007] With this configuration, the first stand for installing the calibration tool can be placed above the measurement device using multiple supports provided around the measurement device, thereby reducing the time and effort required for calibration work and making it easier to install the calibration tool.

[0008] (2) In the above (1), the calibration equipment may further include a fan that blows air to the calibration tool.

[0009] When calibrating a measuring device in a room temperature environment, condensation may occur in the calibration tool, which has been cooled by liquid nitrogen. If the measuring device is calibrated in a state where condensation has occurred, the calibration accuracy may decrease. With the above-described configuration, the possibility of condensation occurring in the calibration tool filled with liquid nitrogen can be reduced, thereby preventing a decrease in the calibration accuracy of the measuring device.

[0010] (3) In the above (2), the first frame may include an opening, and the fan may send air to the calibration instrument through the opening.

[0011] If condensation occurs on the bottom surface of the calibration tool, which is the surface facing the measurement device, there is a high possibility that the calibration accuracy of the measurement device will decrease. With the above-mentioned configuration, air can be more reliably blown toward the bottom surface of the calibration tool, thereby more reliably reducing the possibility of condensation occurring on the bottom surface.

[0012] (4) In the above (2) or (3), the airflow direction of the fan may intersect with the vertical direction of the calibration device so that the fan blows air toward the bottom surface of the calibration fixture.

[0013] This configuration can more reliably reduce the possibility of condensation occurring on the bottom surface of the calibration fixture.

[0014] (5) In any of (2) to (4) above, the calibration equipment may be provided with a plurality of the fans, and the fans may be arranged in a row so as to blow air in one direction toward the calibration tool.

[0015] This configuration makes it possible to prevent the air flow from one fan from interfering with the air flow from another fan, thereby enabling air to be blown to the calibration instrument more efficiently.

[0016] (6) In any one of the above (1) to (5), the calibration equipment may further include an alignment unit for aligning the calibration tool with the antenna of the measurement device.

[0017] This configuration makes it easy to align the calibration tool with the antenna of the measurement device.

[0018] (7) In any one of the above (1) to (6), the calibration equipment may further include the calibration tool having a radio wave absorber provided therein.

[0019] For example, a measuring device measures the brightness temperature of microwaves using the intensity of microwaves radiated from the atmosphere and a reference value of the intensity. This reference value needs to be calibrated, and the above-described configuration makes it possible to more reliably calibrate the reference value using the intensity of microwaves radiated from a radio wave absorber.

[0020] (8) In any of the above (1) to (7), the calibration device may further include the calibration tool including a display unit that indicates the amount of liquid nitrogen filled.

[0021] With this configuration, the amount of liquid nitrogen filled in the calibration tool can be easily determined.

[0022] (9) In any of (1) to (8) above, the calibration equipment may further include a second frame on which the measuring device is installed, the plurality of supports may be integrally attached to the second frame, and the first frame may be supported above the second frame by the plurality of supports at the plurality of receiving portions.

[0023] With this configuration, the measuring device can be installed stably, and the first frame can be placed stably above the second frame.

[0024] (10) In the above (9), the second stand may be provided at a distance from an installation surface of the calibration equipment.

[0025] With this configuration, the influence of the temperature of the installation surface of the calibration equipment on the measurement device can be reduced, thereby further improving the calibration accuracy of the measurement device.

[0026] (11) In the above (9), wheels may be provided below the second frame.

[0027] This configuration allows the calibration equipment to be easily moved.

[0028] (12) A measurement unit according to an embodiment of the present disclosure includes any one of the calibration instruments (1) to (11) above, the measurement device, and the plurality of pillars, and the plurality of pillars support the first frame at the plurality of receiving portions.

[0029] With this configuration, the first stand for installing the calibration tool can be placed above the measurement device using multiple support columns provided around the measurement device, making it easy to install the calibration tool.

[0030] (13) In (12) above, each of the plurality of supports may be provided with a through hole that passes through the support along the width direction of the support, and the measurement unit may further include a fiber material that is inserted into the through hole.

[0031] With this configuration, in addition to the multiple supports, the fiber material can prevent birds from landing on the measuring device, for example, thereby improving the bird-repellent effect.

[0032] (14) In (12) or (13) above, each of the plurality of pillars may be provided with a plurality of the through holes arranged in a row in the longitudinal direction of the pillar, and the difference between the position of the through hole in the longitudinal direction of the pillar and the position of the corresponding through hole in the longitudinal direction of another pillar may be less than a predetermined value.

[0033] This configuration allows multiple fiber materials to be provided around the measuring device, further improving the bird-repelling effect. Also, since the difference between the position of a through-hole in the length direction of one support and the position of a corresponding through-hole in the length direction of another support is equal to or less than a predetermined value, the efficiency of the work of inserting the fiber materials can be improved.

[0034] (15) A method for calibrating a measuring device according to an embodiment of the present disclosure includes the steps of preparing a calibration device having a first stand on which a calibration tool filled with liquid nitrogen is placed, and supporting the first stand at a plurality of receiving portions included in the first stand on a plurality of supports provided around the measuring device to be calibrated.

[0035] This method allows the first stand for installing the calibration tool to be placed above the measurement device using multiple supports provided around the measurement device, thereby reducing the time and effort required for the calibration work and making it easier to install the calibration tool. [Effects of the Invention]

[0036] According to the present disclosure, calibration equipment can be easily installed. [Brief explanation of the drawings]

[0037] [Figure 1] FIG. 1 is a perspective view showing a configuration of a measurement unit according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view illustrating the configuration of the measurement unit according to the embodiment of the present disclosure. [Figure 3] FIG. 3 is a diagram illustrating a configuration of a support column of a measurement unit according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is a bottom view showing the configuration of the first stand of the calibration equipment according to the embodiment of the present disclosure. [Figure 5] FIG. 5 is a side view showing the configuration of a calibration device according to an embodiment of the present disclosure. [Figure 6] FIG. 6 is a side view showing a part of the configuration of the calibration device according to the embodiment of the present disclosure. [Figure 7] FIG. 7 is a cross-sectional view showing an example of the configuration of a calibration tool in the calibration device according to the embodiment of the present disclosure. [Figure 8] FIG. 8 is a flowchart defining an example method for calibrating a microwave radiometer using a calibration device according to an embodiment of the present disclosure. [Figure 9] FIG. 9 is a flowchart defining another example of a method for calibrating a microwave radiometer using a calibration device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0038] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, identical or corresponding parts are designated by the same reference numerals, and their description will not be repeated. Furthermore, at least some of the embodiments described below may be combined in any manner.

[0039] [Measurement unit configuration] FIG. 1 is a perspective view showing a configuration of a measurement unit according to an embodiment of the present disclosure. FIG. 2 is an exploded perspective view showing a configuration of a measurement unit according to an embodiment of the present disclosure. With reference to FIGS. 1, 2, and 3, measurement unit 201 includes calibration device 101, microwave radiometer 21, a plurality of supports 41, and a plurality of fiber materials 51. Calibration device 101 is a device for calibrating microwave radiometer 21. Microwave radiometer 21 is an example of a measurement device.

[0040] (Microwave Radiometer) The microwave radiometer 21 measures the amount of water vapor in the atmosphere. Specifically, for example, the microwave radiometer 21 receives microwaves emitted from the atmosphere and measures the brightness temperature of the microwaves based on the intensity of the received microwaves. The microwave radiometer 21 then calculates the amount of water vapor in the atmosphere by substituting the measured brightness temperature into a predetermined arithmetic expression.

[0041] (post) The plurality of support columns 41 are provided around the microwave radiometer 21 when the microwave radiometer 21 is calibrated. For example, the plurality of support columns 41 are integrally attached to the second frame 12 by fastening members such as screws.

[0042] 1 and 2, the measurement unit 201 includes a plurality of support pillars 41, namely, support pillars 41A, 41B, 41C, and 41D. Each support pillar 41 extends in the z-axis direction and is provided, for example, to scare away birds.

[0043] 3 is a diagram illustrating the configuration of the support columns of the measurement unit according to the embodiment of the present disclosure. Referring to FIGS. 2 and 3, for example, each of the plurality of support columns 41 is provided with a plurality of through-holes 71 that penetrate the support column 41 along the width direction of the support column 41. The through-holes 71 are, for example, circular in shape. The fiber material 51 is inserted through the through-holes 71 of each support column 41.

[0044] The multiple through holes 71 are aligned in a row in the length direction of the support 41. The difference between the position of a through hole 71 in the length direction of the support 41 and the position of a corresponding through hole 71 in the length direction of another support 41 is equal to or smaller than a predetermined value. Specifically, for example, the position of a through hole 71 in the length direction of the support 41 is the same as the position of a corresponding through hole 71 in the length direction of the other support 41.

[0045] (calibration equipment) The calibration device 101 calibrates the brightness temperature measurement function of the microwave radiometer 21. The calibration device 101 includes a calibration fixture 10, a first stand 11, a second stand 12, and a fan 13.

[0046] <Calibration equipment> The calibration instrument 10 is filled with liquid nitrogen. The calibration instrument 10 is, for example, a rectangular parallelepiped container. The calibration instrument 10 is made of, for example, polystyrene foam. The calibration instrument 10 may include a display unit that indicates the amount of liquid nitrogen filled.

[0047] 1 and 2, the axis along the vertical direction is defined as the z-axis, the axis perpendicular to the z-axis is defined as the x-axis, and the axis perpendicular to the x-axis and z-axis is defined as the y-axis.

[0048] <First stand> The first mount 11 is a mount for placing the calibration tool 10. For example, the shape of the first mount 11 is rectangular in a plan view. The material of the first mount 11 is, for example, metal. The first mount 11 includes an opening P. The calibration tool 10 is placed on the first mount 11 so as to cover the opening P.

[0049] The liquid nitrogen is filled into the calibration tool 10 while the calibration tool 10 is installed on the first frame 11. This allows the calibration work of the microwave radiometer 21 to be performed more safely than a method in which the calibration tool 10 is filled with liquid nitrogen and then the calibration tool 10 is placed above the microwave radiometer 21.

[0050] Fig. 4 is a bottom view showing the configuration of a first mount of a calibration instrument according to an embodiment of the present disclosure. Referring to Fig. 4, first mount 11 includes a plurality of receiving portions 18. In the example shown in Fig. 4, first mount 11 includes receiving portions 18A, 18B, 18C, and 18D, which are the plurality of receiving portions 18. Each receiving portion 18 is, for example, a recess.

[0051] The first frame 11 is detachably supported by the plurality of support columns 41 at the plurality of receiving portions 18. More specifically, the first frame 11 is detachably supported by the plurality of support columns 41 by each receiving portion 18 abutting against the upper portion of the corresponding support column 41. Specifically, for example, when the microwave radiometer 21 is calibrated, the upper portion of each support column 41 is fitted into the corresponding receiving portion 18.

[0052] The first frame 11 is provided above the second frame 12. More specifically, for example, the first frame 11 is supported above the second frame 12 by a plurality of support columns 41 at a plurality of receiving portions 18. Specifically, for example, the first frame 11 is supported above the second frame 12 by each receiving portion 18 abutting against the upper portion of the corresponding support column 41.

[0053] <Second stand> 5 is a side view showing a configuration of a calibration device according to an embodiment of the present disclosure. With reference to FIGS. 1, 2, and 5, second mount 12 is a mount for installing microwave radiometer 21. Second mount 12 has a rectangular shape in a plan view. Second mount 12 is made of a material such as metal.

[0054] For example, the bottom surface 12a of the second frame 12 is in contact with the installation surface S of the calibration equipment 101. The second frame 12 may be provided at a distance D from the installation surface S. Also, the calibration equipment 101 may be provided with wheels below the second frame 12 to facilitate movement of the calibration equipment 101.

[0055] Furthermore, second frame 12 may include a guide portion for guiding microwave radiometer 21. Specifically, for example, when microwave radiometer 21 is installed on second frame 12, second frame 12 may include, as the guide portion, a rail portion for guiding microwave radiometer 21 by sliding it in the x-axis direction.

[0056] Furthermore, the second frame 12 may include a height adjustment unit that can adjust the height of the main surface Q from the installation surface S of the calibration equipment 101 in accordance with the size of the microwave radiometer 21. Specifically, for example, the second frame 12 may include, as the height adjustment unit, a rail unit that can slide in the z-axis direction on the main surface of the second frame 12 on which the microwave radiometer 21 is installed.

[0057] <Fan> Each fan 13 blows air toward the calibration fixture 10. Each fan 13 is provided on the first frame 11. Specifically, for example, each fan 13 is provided on a side surface 11a of the first frame 11 that faces the +y-axis direction.

[0058] For example, the fans 13 are arranged in a line in the x-axis direction so as to blow air in one direction toward the calibration fixture 10.

[0059] 6 is a side view showing a part of the configuration of the calibration equipment according to the embodiment of the present disclosure, and is a side view of the inside of the first frame 11 of the calibration equipment 101.

[0060] 6, for example, a plurality of window portions 81 are provided on a surface 11b behind a side surface 11a of the first frame 11 so that the air blowing surface 13a of each fan 13 is exposed from the surface 11b. Each fan 13 blows air to the bottom surface 10a of the calibration fixture 10 through the window portions 81 and the opening P of the first frame 11.

[0061] The airflow direction of each fan 13 may intersect with the vertical direction of the calibration device 101, i.e., the z-axis direction, so that the fan 13 blows air toward the bottom surface 10a of the calibration fixture 10. In other words, each fan 13 may be fixed at an angle with respect to the side surface 11a of the first frame 11 so that the airflow surface 13a of the fan 13 faces the bottom surface 10a of the calibration fixture 10.

[0062] Furthermore, in the present embodiment, the plurality of fans 13 are arranged in a row on the side surface 11a of the first frame 11, but this is not limiting. For example, at least one of the plurality of fans 13 may be provided on another side surface of the first frame 11 instead of the side surface 11a of the first frame 11. Furthermore, at least one of the fans 13 may be provided on the second frame 12, not just the first frame 11.

[0063] (Radio wave absorber) 7 is a cross-sectional view showing an example of the configuration of a calibration tool in the calibration equipment according to the embodiment of the present disclosure. Referring to Fig. 7, for example, a radio wave absorber 61 is provided inside calibration tool 10.

[0064] Radio wave absorber 61 emits microwaves for calibrating microwave radiometer 21. The material of radio wave absorber 61 is, for example, a dielectric material. When calibration tool 10 is filled with liquid nitrogen, radio wave absorber 61 is immersed in the liquid nitrogen.

[0065] Here, the microwave radiometer 21 shown in FIG. 1 measures the brightness temperature of the microwave based on the intensity of the microwave in the atmosphere and a reference intensity Rs calculated in advance.

[0066] For example, the microwave radiometer 21 calculates the reference intensity Rs based on the intensity of the microwave radiated from the radio wave absorber 61. Specifically, for example, the microwave radiometer 21 calculates the reference intensity Rs based on the intensity R1 of the microwave radiated from the radio wave absorber 61 having an absolute temperature of 77 K and the intensity R2 of the microwave radiated from the radio wave absorber 61 having an absolute temperature of 300 K, i.e., from the radio wave absorber 61 in a room temperature environment.

[0067] Microwave radiometer 21 calibrates reference intensity Rs using calibration device 101 shown in Fig. 1. Specifically, when calibration tool 10 is filled with liquid nitrogen, microwave radiometer 21 receives microwaves radiated from radio wave absorber 61 and measures intensity R1 of the microwaves. When calibration tool 10 is not filled with liquid nitrogen, microwave radiometer 21 receives microwaves radiated from radio wave absorber 61 and measures intensity R2 of the microwaves. Then, microwave radiometer 21 calibrates reference intensity Rs based on the measured intensities R1 and R2.

[0068] The calibration device 101 may include an alignment unit for aligning the calibration tool 10 with the antenna of the microwave radiometer 21. Specifically, for example, an alignment unit for aligning the calibration tool 10 with the antenna of the microwave radiometer 21 in the x-axis direction and an alignment unit for aligning the calibration tool 10 with the antenna of the microwave radiometer 21 in the y-axis direction may be provided on the first frame 11. The calibration device 101 may also include a horizontal adjustment unit that allows the second frame 12 to be installed horizontally on the installation surface S of the calibration device 101.

[0069] [Operation flow] FIG. 8 is a flowchart defining an example method for calibrating a microwave radiometer using a calibration device according to an embodiment of the present disclosure.

[0070] Referring to FIG. 8, first, the user of calibration equipment 101 installs second stand 12 of calibration equipment 101 on installation surface S (step ST101).

[0071] Next, the user installs the microwave radiometer 21 on the second stand 12 of the calibration equipment 101 (step ST102).

[0072] Next, the user places a plurality of supports 41 so as to surround microwave radiometer 21 (step ST103).

[0073] Next, the user inserts the fiber material 51 into the through-holes 71 formed in each of the supports 41 (step ST104).

[0074] Next, the user prepares the first stand 11 of the calibration equipment 101 (step ST105).

[0075] Next, the user fits the corresponding support posts 41 into each of the plurality of receiving portions 18 included in the first frame 11, thereby supporting the first frame 11 with the plurality of support posts 41. That is, the user places the first frame 11 above the microwave radiometer 21 (step ST106).

[0076] Next, the user places the calibration tool 10 on the first stand 11 of the calibration equipment 101, and fills the calibration tool 10 with liquid nitrogen (step ST107).

[0077] Next, the user causes the fan 13 of the calibration equipment 101 to blow air toward the calibration instrument 10 (step ST108).

[0078] Next, the user calibrates the microwave radiometer 21 while the fan 13 is blowing air toward the calibration tool 10 (step ST109).

[0079] 9 is a flowchart defining another example of a method for calibrating a microwave radiometer using the calibration apparatus according to the embodiment of the present disclosure. Fig. 9 illustrates the calibration method in the case where the microwave radiometer 21 has already been installed on the second stand 12 of the calibration apparatus 101 and the fiber material 51 has already been inserted through the through-holes 71 formed in each support 41.

[0080] Referring to FIG. 9, first, the microwave radiometer 21 is placed on the second stand 12 of the calibration equipment 101, and the fiber material 51 is inserted into the through holes 71 formed in each of the plurality of supports 41 provided around the microwave radiometer 21. In this state, the user prepares the first stand 11 of the calibration equipment 101 (step ST201).

[0081] Next, the user fits the corresponding support posts 41 into each of the plurality of receiving portions 18 included in the first frame 11, thereby supporting the first frame 11 with the plurality of support posts 41. That is, the user places the first frame 11 above the microwave radiometer 21 (step ST202).

[0082] Next, the user places the calibration tool 10 on the first stand 11 of the calibration equipment 101, and fills the calibration tool 10 with liquid nitrogen (step ST203).

[0083] Next, the user causes the fan 13 of the calibration equipment 101 to blow air toward the calibration instrument 10 (step ST204).

[0084] Next, the user calibrates the microwave radiometer 21 while the fan 13 is blowing air toward the calibration tool 10 (step ST205).

[0085] In the embodiment of the present disclosure, the calibration target of the calibration device 101 is the microwave radiometer 21, but this is not limited to this. The calibration target may also be a measurement device that measures other types of electromagnetic waves than microwaves, specifically, a measurement device that measures radio waves, light, radio waves, X-rays, etc. other than microwaves. The calibration target is not limited to a measurement device that measures electromagnetic waves, but may also be any measurement device that measures physical phenomena, chemical phenomena, biological phenomena, etc.

[0086] The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0087] 10 Calibration equipment 11 First Mount 12 Second Mount 13 Fan 18 Receiving part 21 Microwave Radiometer 41 Post 51 Fiber materials 61 Radio wave absorber 71 Through hole 81 Window 101 Calibration equipment 201 Measurement Unit P opening S Installation surface

Claims

1. a first stand on which a calibration tool filled with liquid nitrogen is placed; the first mount includes a plurality of receiving portions; The first frame is detachably supported at the plurality of receiving portions by a plurality of support columns provided around the measuring device to be calibrated.

2. The calibration device further comprises: The calibration equipment of claim 1 , further comprising a fan for blowing air through the calibration fixture.

3. the first mount includes an opening; The calibration equipment of claim 2 , wherein the fan blows air through the opening to the calibration fixture.

4. 4. The calibration instrument according to claim 2, wherein the airflow direction of the fan intersects with the up-down direction of the calibration instrument so that the fan blows air toward a bottom surface of the calibration fixture.

5. the calibration equipment comprises a plurality of the fans; 4. The calibration equipment according to claim 2, wherein the plurality of fans are arranged in a line so as to blow air in one direction toward the calibration fixture.

6. The calibration device further comprises:

3. The calibration equipment according to claim 1, further comprising an alignment unit for aligning the calibration tool with an antenna of the measurement device.

7. The calibration device further comprises:

3. The calibration equipment according to claim 1, further comprising the calibration tool having a radio wave absorber disposed therein.

8. The calibration device further comprises:

3. The calibration device according to claim 1, further comprising a display unit that displays the amount of liquid nitrogen filled.

9. The calibration device further comprises: a second stand on which the measuring device is installed, the plurality of columns are integrally attached to the second frame, 3. The calibration equipment according to claim 1, wherein the first frame is supported above the second frame by the plurality of support columns at the plurality of receiving portions.

10. The calibration equipment according to claim 9 , wherein the second stand is provided at a distance from an installation surface of the calibration equipment.

11. 10. The calibration equipment of claim 9, wherein wheels are provided below the second platform.

12. The calibration device according to claim 1 or 2; the measuring device; the plurality of support columns; The plurality of support columns detachably support the first frame at the plurality of receiving portions.

13. Each of the plurality of support columns has a through hole that penetrates the support column along a width direction of the support column, The measurement unit further comprises: The measuring unit according to claim 12 , further comprising a fiber material inserted into the through-hole.

14. Each of the plurality of support columns is provided with a plurality of the through holes aligned in a longitudinal direction of the support column, The measuring unit according to claim 13 , wherein a difference between a position of the through-hole in the length direction of the support and a position of a corresponding through-hole in the length direction of another support is equal to or smaller than a predetermined value.

15. preparing a calibration apparatus having a first stand on which a calibration tool filled with liquid nitrogen is placed; and removably supporting the first frame at a plurality of receiving portions included in the first frame by a plurality of supports provided around the measuring device to be calibrated.

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