CN116643236A - Underwater low-frequency electromagnetic wave positioning method - Google Patents
Underwater low-frequency electromagnetic wave positioning method Download PDFInfo
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- CN116643236A CN116643236A CN202310572953.4A CN202310572953A CN116643236A CN 116643236 A CN116643236 A CN 116643236A CN 202310572953 A CN202310572953 A CN 202310572953A CN 116643236 A CN116643236 A CN 116643236A
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- 238000000034 method Methods 0.000 title claims abstract description 29
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 37
- 230000005672 electromagnetic field Effects 0.000 claims abstract description 14
- 230000005684 electric field Effects 0.000 claims abstract description 10
- 230000005855 radiation Effects 0.000 claims abstract description 7
- 238000012545 processing Methods 0.000 claims abstract description 4
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 238000001914 filtration Methods 0.000 claims description 3
- 239000013535 sea water Substances 0.000 abstract description 6
- 238000005516 engineering process Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000000644 propagated effect Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
- G01S5/12—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/30—Assessment of water resources
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
The application discloses an underwater low-frequency electromagnetic wave positioning method, which comprises the following steps: 1. erecting a low-frequency electromagnetic wave transmitting system on a ship; 2. arranging electrodes with ends exposed in water under water; 3. a set of electromagnetic wave receiving system is arranged on the submarine; 4. the program calculates the amplitude of each component of the electromagnetic field point of the radiation source; 5. acquiring and processing a received voltage signal; 6. calculating the Ey component amplitude of the electric field; 7. obtaining contour lines of two emission sources at receiving points; 8. and obtaining the intersection point of the contour lines, wherein the intersection point is the coordinate of the receiving point. According to the application, the transmitting system is erected on a ship, the wires with the two ends exposed in water are arranged under water to be equivalent to couple sources, an electromagnetic field is formed around the wires, the electromagnetic wave receiving system is arranged on the submarine, the relative positions of the receiving points and the two transmitting sources are determined according to the magnitude of electric field components of the receiving points, so that the positioning is realized, and the positioning equipment has a simple structure and is detachable and can be applied to positioning the submarine in sea water.
Description
Technical Field
The application relates to the field of underwater electromagnetic wave positioning, in particular to an underwater low-frequency electromagnetic wave positioning method.
Background
Along with the sequential exploitation of resources on landing, people's eyes start to throw to ocean resources, and the underwater target positioning technology has important significance to the development of ocean resources, and sound waves are always the main mode of underwater positioning at present, and the propagation range can reach tens of kilometers, so that the underwater target positioning technology is a relatively universal positioning technology.
In the existing patent document CN1614441A automatic positioning method and system thereof, a positioning method is disclosed, the positioning method has some limitations, sound waves are difficult to influence by multipath, temperature, water pressure and turbidity in sea water, the sound wave propagation speed is slower, the sound wave positioning equipment is large in size, the Doppler frequency shift and serious noise are easy to occur when the sound waves are propagated in the sea water due to the difficulty in baseline arrangement. Therefore, an underwater low-frequency electromagnetic wave positioning method is provided for the problems.
Disclosure of Invention
The embodiment provides an underwater low-frequency electromagnetic wave positioning method which is used for solving the problems that the common underwater positioning method in the prior art is easily affected by multipath, temperature, water pressure and turbidity in shallow water, the sound wave propagation speed is low, the sound wave positioning equipment is large in size, the Doppler frequency shift and serious noise are easily generated when the underwater sound is propagated in seawater due to the difficulty in baseline arrangement.
According to an aspect of the present application, there is provided an underwater low frequency electromagnetic wave positioning method comprising the steps of:
1. simultaneously erecting low-frequency electromagnetic wave emission systems on two ships at different known positions, wherein the electromagnetic wave emission frequencies are respectively 10Hz and 100Hz;
2. arranging electrodes with ends exposed in water under water, wherein the electrodes are connected with a ship launching system through wires;
3. a set of electromagnetic wave receiving system is arranged on the submarine, and the receiving antenna is an electrode with the end exposed in water;
4. calculating the depth of the submarine through a water depth sensor, determining depth information, and calculating Ey component amplitude of an underwater long straight wire emission source at a plane radiation field point where the submarine is positioned through MATLAB;
5. acquiring a voltage signal received by a receiving system, and separating out voltage signals of two specific frequency points of 10Hz and 100Hz;
6. calculating the Ey component amplitude of the electric field from the two voltage signal amplitudes in step 5;
7. 6, comparing the calculated result with the calculated result in the step 4 to obtain the contour line of the two emission sources at the receiving point;
8. and obtaining an intersection point of the contour lines, wherein the intersection point of the contour lines is the coordinates of the receiving points because the positions of the coordinates of the two transmitting sources are known.
Further, in step 1, the low-frequency electromagnetic wave transmitting system includes a transmitting control system, a driving system and a power supply system.
Further, in the step 1, a computing system for computing the coordinates of the receiver is installed on the ship.
Further, in the step 1, the number of the low-frequency electromagnetic wave transmitting systems is two, and the two low-frequency electromagnetic wave transmitting systems respectively erect different known positions and transmit electromagnetic waves of different frequency points, which are respectively 10Hz and 100Hz.
In step 2, wires with both ends exposed in water are arranged underwater and connected with equipment on a ship, the wires are connected with a power supply system on the ship, the power supply system supplies power to the wires, the wires can be equivalently a couple source after being supplied with power, an electromagnetic field is formed in surrounding space, and low-frequency electromagnetic waves are emitted in the water.
In step 2, wires with both ends exposed in water are arranged underwater and connected with equipment on the ship, the wires are connected with the equipment on the ship, the power supply system supplies power to the wires, the wires can be equivalently a couple source after being supplied with power, an electromagnetic field is formed in surrounding space, and low-frequency electromagnetic waves are emitted in the water.
Further, in the step 2, the electromagnetic field strength formed by the couple source is:
in step 3, an electromagnetic wave receiving system for detecting the magnitude of each component of the electromagnetic field of the receiving point is installed on the underwater vehicle, and a water depth sensor for determining the depth of the position of the underwater vehicle is arranged in the electromagnetic wave receiving system.
In step 3, the electromagnetic wave receiving system is provided with a computer, an amplifying module, a filtering module and an analog-to-digital conversion module, and the electromagnetic wave is received by the receiving system on the submarine at the same time and enters the computer for data processing after being amplified, filtered and analog-to-digital converted.
Further, in the step 4, the depth information of the submarine is obtained through a water depth sensor, and is substituted into a MATLAB program to calculate the plane radiation field distribution of the submarine, so that the Ey component amplitude of each field point is obtained.
In step 5, the signals received by the receiving system are filtered and fourier transformed to separate out the voltage signals of the specific frequency points of the two transmitting sources.
Further, in the step 6, the conversion formula of the electric field component amplitude and the voltage signal amplitude is e=u/d, and d is the distance between the two electrodes of the receiving end.
Further, in the step 7, the calculation result in the step 6 is compared with the calculation result in the step 4, the point with the error smaller than 1e-8 compared with the calculation result in the step 6 in the calculation result in the step 4 is found, and the searched point is used as the contour line.
In step 8, the two contour lines drawn in step 7 are used to calculate the intersection point of the two contour lines, and since the coordinate positions of the two emission sources are known and there is only one intersection point of the contour lines, the intersection point is the coordinate position of the receiving point.
According to the embodiment of the application, the transmitting system is erected on a ship, the wires with the two ends exposed in water are arranged under water to be equivalent to a couple source, an electromagnetic field is formed around the wires, the electromagnetic wave receiving system is arranged on the submarine, the relative positions of the receiving points and the two transmitting sources are determined according to the electric field of the receiving points, so that the positioning device is simple in structure and detachable, and can be applied to positioning of the submarine in sea water.
Drawings
In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.
FIG. 1 is a flow chart of an embodiment of the present application.
Detailed Description
In order that those skilled in the art will better understand the present application, a technical solution in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present application without making any inventive effort, shall fall within the scope of the present application.
It should be noted that the terms "first," "second," and the like in the description and the claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe the embodiments of the application herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
In the present application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are only used to better describe the present application and its embodiments and are not intended to limit the scope of the indicated devices, elements or components to the particular orientations or to configure and operate in the particular orientations.
Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in the present application will be understood by those of ordinary skill in the art according to the specific circumstances.
Furthermore, the terms "mounted," "configured," "provided," "connected," "coupled," and "sleeved" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; may be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements, or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.
Referring to fig. 1, an underwater low-frequency electromagnetic wave positioning method includes the following steps:
1. simultaneously erecting low-frequency electromagnetic wave emission systems on two ships at different known positions, wherein the electromagnetic wave emission frequencies are respectively 10Hz and 100Hz;
2. arranging electrodes with ends exposed in water under water, wherein the electrodes are connected with a ship launching system through wires;
3. a set of electromagnetic wave receiving system is arranged on the submarine, and the receiving antenna is an electrode with the end exposed in water;
4. calculating the depth of the submarine through a water depth sensor, determining depth information, and calculating Ey component amplitude of an underwater long straight wire emission source at a plane radiation field point where the submarine is positioned through MATLAB;
5. acquiring a voltage signal received by a receiving system, and separating out voltage signals of two specific frequency points of 10Hz and 100Hz;
6. calculating the Ey component amplitude of the electric field from the two voltage signal amplitudes in step 5;
7. 6, comparing the calculated result with the calculated result in the step 4 to obtain the contour line of the two emission sources at the receiving point;
8. and obtaining an intersection point of the contour lines, wherein the intersection point of the contour lines is the coordinates of the receiving points because the positions of the coordinates of the two transmitting sources are known.
Further, in step 1, the low-frequency electromagnetic wave transmitting system includes a transmitting control system, a driving system and a power supply system.
Further, in the step 1, a computing system for computing the coordinates of the receiver is installed on the ship.
Further, in the step 1, the number of the low-frequency electromagnetic wave transmitting systems is two, and the two low-frequency electromagnetic wave transmitting systems respectively erect different known positions and transmit electromagnetic waves of different frequency points, which are respectively 10Hz and 100Hz.
In step 2, wires with both ends exposed in water are arranged underwater and connected with equipment on a ship, the wires are connected with a power supply system on the ship, the power supply system supplies power to the wires, the wires can be equivalently a couple source after being supplied with power, an electromagnetic field is formed in surrounding space, and low-frequency electromagnetic waves are emitted in the water.
In step 2, wires with both ends exposed in water are arranged underwater and connected with equipment on the ship, the wires are connected with the equipment on the ship, the power supply system supplies power to the wires, the wires can be equivalently a couple source after being supplied with power, an electromagnetic field is formed in surrounding space, and low-frequency electromagnetic waves are emitted in the water.
Further, in the step 2, the electromagnetic field strength formed by the couple source is:
in step 3, an electromagnetic wave receiving system for detecting the magnitude of each component of the electromagnetic field of the receiving point is installed on the underwater vehicle, and a water depth sensor for determining the depth of the position of the underwater vehicle is arranged in the electromagnetic wave receiving system.
In step 3, the electromagnetic wave receiving system is provided with a computer, an amplifying module, a filtering module and an analog-to-digital conversion module, and the electromagnetic wave is received by the receiving system on the submarine at the same time and enters the computer for data processing after being amplified, filtered and analog-to-digital converted.
Further, in the step 4, the depth information of the submarine is obtained through a water depth sensor, and is substituted into a MATLAB program to calculate the plane radiation field distribution of the submarine, so that the Ey component amplitude of each field point is obtained.
In step 5, the signals received by the receiving system are filtered and fourier transformed to separate out the voltage signals of the specific frequency points of the two transmitting sources.
Further, in the step 6, the conversion formula of the electric field component amplitude and the voltage signal amplitude is e=u/d, and d is the distance between the two electrodes of the receiving end.
Further, in the step 7, the calculation result in the step 6 is compared with the calculation result in the step 4, the point with the error smaller than 1e-8 compared with the calculation result in the step 6 in the calculation result in the step 4 is found, and the searched point is used as the contour line.
In step 8, the two contour lines drawn in step 7 are used to calculate the intersection point of the two contour lines, and since the coordinate positions of the two emission sources are known and there is only one intersection point of the contour lines, the intersection point is the coordinate position of the receiving point.
The application has the advantages that:
the electromagnetic wave receiving system is arranged on the submarine, and the relative positions of the receiving points and the two emission sources are determined according to the electric field of the receiving points, so that the positioning device is simple in structure and detachable and can be applied to positioning the submarine in the sea water.
The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (12)
1. An underwater low-frequency electromagnetic wave positioning method is characterized in that: the underwater low-frequency electromagnetic wave positioning method comprises the following steps:
(1) Simultaneously erecting low-frequency electromagnetic wave emission systems on two ships at different known positions, wherein the electromagnetic wave emission frequencies are respectively 10Hz and 100Hz;
(2) Arranging electrodes with ends exposed in water under water, wherein the electrodes are connected with a ship launching system through wires;
(3) A set of electromagnetic wave receiving system is arranged on the submarine, and the receiving antenna is an electrode with the end exposed in water;
(4) Calculating the depth of the submarine through a water depth sensor, determining depth information, and calculating Ey component amplitude of an underwater long straight wire emission source at a plane radiation field point where the submarine is positioned through MATLAB;
(5) Acquiring a voltage signal received by a receiving system, and separating out voltage signals of two specific frequency points of 10Hz and 100Hz;
(6) Calculating the Ey component amplitude of the electric field from the two voltage signal amplitudes in step 5;
(7) 6, comparing the calculated result with the calculated result in the step 4 to obtain the contour line of the two emission sources at the receiving point;
(8) And obtaining an intersection point of the contour lines, wherein the intersection point of the contour lines is the coordinates of the receiving points because the positions of the coordinates of the two transmitting sources are known.
2. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 1, the low-frequency electromagnetic wave transmitting system comprises a transmitting control system, a driving system and a power supply system.
3. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 1, the number of the low-frequency electromagnetic wave transmitting systems is two, and the two low-frequency electromagnetic wave transmitting systems respectively erect different known positions and transmit electromagnetic waves of different frequency points, namely 10Hz and 100Hz.
4. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 2, the wires with the two ends exposed in the water are arranged underwater and are connected with equipment on the ship, the wires are connected with the equipment on the ship, the power supply system supplies power to the wires, the wires can be equivalently a couple source after being supplied with power, an electromagnetic field is formed in the surrounding space, and the purpose of emitting low-frequency electromagnetic waves in the water is achieved.
5. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 2, the electromagnetic field strength formed by the couple source is as follows:
6. the underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 3, an electromagnetic wave receiving system for detecting the magnitude of each component of the electromagnetic field of the receiving point is arranged on the underwater vehicle, and a water depth sensor for determining the depth of the position of the underwater vehicle is arranged in the electromagnetic wave receiving system.
7. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 3, the electromagnetic wave receiving system is provided with a computer, an amplifying module, a filtering module and an analog-to-digital conversion module, and the electromagnetic wave is received by the receiving system on the submarine, amplified, filtered and analog-to-digital converted and then enters the computer for data processing.
8. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 4, the depth information of the submarine is obtained through a water depth sensor, and is substituted into MATLAB program to calculate the plane radiation field distribution of the submarine, so as to obtain Ey component amplitude values of all field points.
9. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 5, the signals received by the receiving system are filtered and fourier transformed, and the voltage signals of the specific frequency points of the two transmitting sources are separated.
10. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 6, the conversion formula of the electric field component amplitude and the voltage signal amplitude is e=u/d, and d is the distance between the two electrodes of the receiving end.
11. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 7, the calculation result in the step 6 is compared with the calculation result in the step 4, the point with the error smaller than 1e-8 between the calculation result in the step 4 and the calculation result in the step 6 is found out, and the searched point is used as an equivalent line.
12. The underwater low-frequency electromagnetic wave positioning method according to claim 1, characterized in that: in the step 8, the intersection point of the two contour lines is obtained by using the two contour lines drawn in the step 7, and the intersection point is the coordinate position of the receiving point because the coordinate positions of the two transmitting sources are known and the contour line has only one intersection point.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310572953.4A CN116643236A (en) | 2023-05-19 | 2023-05-19 | Underwater low-frequency electromagnetic wave positioning method |
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| CN202310572953.4A CN116643236A (en) | 2023-05-19 | 2023-05-19 | Underwater low-frequency electromagnetic wave positioning method |
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