CN103605127A - Underground water ice detection method - Google Patents
Underground water ice detection method Download PDFInfo
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- CN103605127A CN103605127A CN201310556697.6A CN201310556697A CN103605127A CN 103605127 A CN103605127 A CN 103605127A CN 201310556697 A CN201310556697 A CN 201310556697A CN 103605127 A CN103605127 A CN 103605127A
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Abstract
The invention provides an underground water ice detection method. A transmit-receive multiplex antenna and a receiving antenna are installed in a mutual vertical mode. The transmit-receive multiplex antenna emits linear polarized waves to the surface of Mars, and if the transmit-receive multiplex antenna and the receiving antenna receive echoes simultaneously, i.e., the received echoes are elliptically polarized waves, it can be determined that there is water ice underground on the Mars. Compared to a neutron measuring technology in the prior art, the result obtained by use of such a method is more accurate.
Description
Technical field
The present invention relates to electron trade the radar exploration technique field, relate in particular to when a kind of anisotropy of utilizing ice crystal causes radar wave to be propagated in ice sheet and can produce the underground water-ice detection method that the principle of difference appears in echo polarization pattern.
Background technology
The fixed at low temperatures ice of water or melt water is called water-ice.On earth, modal water-ice be summer waterfall become ice fall in winter, it belongs to seasonal ice wall.Objects outside Earth as the moon, Mars on, also have a large amount of water-ices to exist.According to observation, lunar North Pole finds to have a large amount of " water pocket " of water-ice, and this moon exploration activity of likely carrying out for cosmonaut's unmanned probing device provides another alternative survey region.On the celestial body of universe, find that water-ice is very breathtaking discovery, it can be the following cosmonaut who participates in moon landing task natural resources is provided.And become potable water after can melting, or split into oxygen and hydrogen, for cosmonaut and rocket provide breathing gas and fuel.
At present, to the method for the moon and the underground water-ice detection of deep space, be use neutron detection technology.Whether the method is mainly by judging the existence of protium and then judging that planet is underground has water-ice to exist.The party's ratio juris is: because proton is suitable with neutron mass, so neutron and a lot of energy of proton collision meeting loss, epithermal neutron becomes thermal neutron through the rapid slowing down of this collision meeting.If hydrogen is rich in certain region of planet, pass through the neutron in this region and before fleeing from planet, understand very fast " cooling ", the neutron detector in this overhead, region can detect the decline of epithermal neutron flux and the increase of thermal neutron flux so.Therefore hydrogen richness can reflect by the counting rate of certain type of neutron (as epithermal neutron) or the relative value of dissimilar neutron count rate.
Yet, in realizing process of the present invention, applicant finds: the neutron spectra that neutron measurement technology obtains can not be distinguished the different chemical form of hydrogen, therefore uses the method can not obtain the conclusive evidence that underground water-ice exists, and can not determine water-ice layer thickness.
Summary of the invention
(1) technical matters that will solve
In view of above-mentioned technical matters, the invention provides a kind of underground water-ice detection method, utilize dual polarization measuring technique to determine and on the earth or celestial body, whether have water-ice and water-ice layer thickness.
(2) technical scheme
According to an aspect of the present invention, provide a kind of underground water-ice detection method.This underground water-ice detection method comprises: steps A, arranges orthogonal transmitting-receiving multiplex antenna and receiving antenna; Step B, by receiving and dispatching multiplex antenna to the underground emission line polarimetric radar of detecting location ripple; Step C, Real-Time Monitoring transmitting-receiving multiplex antenna and receiving antenna; And step D, if transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, showing that this echo is elliptically polarised wave, detecting location is underground has water-ice.
(3) beneficial effect
From technique scheme, can find out, the underground water-ice detection method of the present invention has following beneficial effect:
(1) mutual vertically arranged transmitting-receiving multiplex antenna and receiving antenna are set, transmitting-receiving multiplex antenna is to martian surface emission line polarized wave, if transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, the echo receiving is elliptically polarised wave, can judge the underground water-ice that exists of Mars, than prior art neutron measurement technology, the result accuracy obtaining is higher;
(2) analyze same polarization echoed signal, obtain the propagation delay τ of radar wave in martian surface overlayer
d1with the propagation delay τ of radar wave in Mars time top layer
d2, and then try to achieve martian surface cover thickness Z
1with Mars time top layer, the i.e. thickness Z of water-ice layer
2.
Accompanying drawing explanation
Figure 1A is according to the principle schematic of the underground water-ice detection method of the embodiment of the present invention;
Figure 1B is according to the process flow diagram of the underground water-ice detection method of the embodiment of the present invention;
Fig. 2 is the antenna scheme of installation that the present embodiment emulation adopts;
Fig. 3 is the coordinate system schematic diagram that the present embodiment emulation adopts;
Fig. 4 is for adopting the same polarization echo power schematic diagram of the present embodiment method emulation;
Fig. 5 is for adopting the same polarization echo power schematic diagram partial enlarged drawing of the present embodiment method emulation;
Fig. 6 is for adopting the cross polarization echo power schematic diagram partial enlarged drawing of the present embodiment method emulation.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.It should be noted that, in accompanying drawing or instructions description, similar or identical part is all used identical figure number.The implementation that does not illustrate in accompanying drawing or describe is form known to a person of ordinary skill in the art in affiliated technical field.In addition, although the demonstration of the parameter that comprises particular value can be provided herein, should be appreciated that, parameter is without definitely equaling corresponding value, but can in acceptable error margin or design constraint, be similar to corresponding value.The direction term of mentioning in embodiment, such as " on ", D score, 'fornt', 'back', " left side ", " right side " etc., be only the direction with reference to accompanying drawing.Therefore, the direction term of use is to be not used for limiting the scope of the invention for explanation.
The invention provides and a kind ofly utilize dual polarization measuring technique to determine to receive the underground water-ice detection method that whether has water-ice and water-ice layer thickness on linear polarization wave line of propagation, amplitude, phase place, locus feature and then definite celestial body.
In one exemplary embodiment of the present invention, provide a kind of underground water ice detection method that carries out on Mars.Figure 1A is according to the principle schematic of the underground water-ice detection method of the embodiment of the present invention.Figure 1B is according to the process flow diagram of the underground water-ice detection method of the embodiment of the present invention.Please refer to Figure 1A and Figure 1B, the underground water-ice detection method of the present embodiment comprises:
Steps A, arranges orthogonal transmitting-receiving multiplex antenna and receiving antenna, and wherein, transmitting-receiving multiplex antenna is for emission line polarized wave and receive same polarization echoed signal, and receiving antenna is used for receiving cross polarization echoed signal, and both are dipole antenna;
Fig. 2 is the antenna scheme of installation that the present embodiment emulation adopts.Please refer to Fig. 2, carrier is the carrier of a rectangular parallelepiped, transmitting-receiving multiplex antenna and receiving antenna are arranged on two right opposites of this rectangular parallelepiped carrier, and be all 45° angle with corresponding face, thereby guarantee that two antennas are vertical, the thickness of rectangular parallelepiped carrier is 2m, and transmitting-receiving multiplex antenna and the center of receiving antenna and the distance of the corresponding installed surface of rectangular parallelepiped carrier are 1.75m.But it will be apparent to those skilled in the art that the present invention is not as limit.
In another embodiment of the present invention, carrier is rectangular parallelepiped, and it is upper that transmitting-receiving multiplex antenna and receiving antenna are arranged on same of rectangular parallelepiped carrier, but both are mutually vertical.In other embodiments of the invention, this carrier can also be hexahedron carrier, and its mounting means is identical with rectangular parallelepiped carrier, as long as guarantee that two antennas are mutually vertical, repeat no more herein.
Step B, by receiving and dispatching multiplex antenna to the underground emission line polarimetric radar of the detecting location on Mars ripple, by transmitting-receiving multiplex antenna and receiving antenna, receive the echo after above-mentioned line polarization wave reflects via underground medium simultaneously, wherein, linear polarization radar wave transmission frequency is UHF wave band and the following wave band of UHF wave band;
Step C, monitoring transmitting-receiving multiplex antenna and receiving antenna, judge whether that both receive echo simultaneously, if both receive echo simultaneously, execution step D, otherwise, execution step G;
Step D, if transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, shows that echo is elliptically polarised wave, and detecting location is underground has water-ice, execution step E;
The anisotropy of ice crystal can produce echo polarization pattern difference while causing radar wave to be propagated in ice sheet, incident electromagnetic wave is at cross polarization direction coupling unit energy, same polarization oriented energy reduces, when emission line polarized wave, can receive the line polarization wave with emission line polarized wave mutually perpendicular direction, the echo receiving is elliptically polarised wave simultaneously.
From the theory of being correlated with, if echo is elliptically polarised wave, can concludes that next top layer is water-ice, and can not be the liquid mediums such as solid dielectric or oil, magma, its theory repeats no more.
The installation direction of receiving antenna is vertical with the installation direction of transmitting-receiving multiplex antenna, and it can receive the line polarization wave with emission line polarized wave mutually perpendicular direction.If transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, can show that echoed signal is elliptically polarised wave, can judge the underground water-ice that exists of Mars.
For the validity of checking the present embodiment, spy has carried out emulation experiment.Fig. 3 is the coordinate system schematic diagram that the present embodiment emulation adopts.Please refer to Fig. 3, the antenna that this emulation experiment is used is 30M half wavelength dipoles sub antenna, and two antennas are arranged on respectively a tetrahedron carrier right opposite, and spacing as shown in Figure 3.600 of sampling numbers, 1646 meters of the degree of depth, transmitting radar wave centre frequency is 179MHz.
Please refer to Fig. 3, due to the anisotropy of ice medium, incident electromagnetic wave is propagated and be there will be orthogonal two components in ice sheet, and the direction of these two components is along with propagation rotates.In figure, the coordinate shown in (x ', y ', z ') is initial coordinate system, that is observation coordinate system, and emitting antenna is θ ' with the angle that initial coordinate is.(x
i, y
i, z
i) shown in coordinate be the coordinate system of electromagnetic wave while propagating in i ice sheet, the angle of emitting antenna and this coordinate system is θ
i.
Figure 4 shows that the same polarization echo power schematic diagram that adopts the emulation of the present embodiment method, Fig. 5 is for adopting the same polarization echo power schematic diagram partial enlarged drawing of the present embodiment method emulation, and Fig. 6 is for adopting the cross polarization echo power schematic diagram partial enlarged drawing of the present embodiment method emulation.By Fig. 4, Fig. 5 and Fig. 6, can be seen, when linear polarization radar wave incides water-ice medium, the echo receiving is elliptically polarised wave, has proved validity and the practicality of the present embodiment method.
Step e, receives first peak value of echo and the time difference between second peak value by transmitting-receiving multiplex antenna and receiving antenna, obtains the first propagation delay τ of linear polarization radar wave in martian surface overlayer
d1, by transmitting-receiving multiplex antenna and receiving antenna, receive second peak value of echo and the time difference between the 3rd peak value, obtain the second propagation delay τ of linear polarization radar wave in Mars time top layer-water-ice layer
d2;
Step F, by the first propagation delay τ
d1with the second propagation delay τ
d2, according to following formula, obtain martian surface cover thickness Z
1with Mars time top layer, the i.e. thickness Z of water-ice layer
2.
In formula 1 and 2, c is the light velocity; ε
r1for martian surface overlayer medium relative dielectric constant.According to Clifford model, Mars overlayer principal ingredient is Irish touchstone, and relative dielectric constant is ε
r1=7.1; ε
r2for the specific inductive capacity of Mars time surface materials-water-ice layer, ε
r2=3.15.
Step G, mars exploration position is underground does not have water-ice, and flow process finishes.
So far, by reference to the accompanying drawings the present embodiment be have been described in detail.According to above, describe, those skilled in the art should have clearly understanding to the underground water-ice detection method of the present invention.
In addition, the above-mentioned definition to each element and method is not limited in various concrete structures, shape or the mode of mentioning in embodiment, and those of ordinary skill in the art can know simply and replace it, for example:
(1) although above-described embodiment be take the detection of the underground water-ice of Mars and described as example, the underground water-ice that the present invention is applied under other scenes is equally surveyed, as the detection of the underground water-ice of the moon;
(2) use the form of antenna to adopt in an embodiment dipole antenna to describe, but Yagi antenna, log-periodic antenna, loop antenna, the antenna of falling V are all applicable to the present invention.
In sum, the invention provides a kind of underground water-ice detection method that adopts dual polarization measuring technique, it is measured with mutual vertically arranged two antennas; An antenna receiving-sending is multiplexing, emission line polarized wave and reception same polarization echoed signal; Another root antenna is only made receiving antenna, receives cross polarization echoed signal, if transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, the echo receiving is elliptically polarised wave, can judge the underground water-ice that exists, afterwards by analyzing the τ of same polarization echo
d1and τ
d2can judge the thickness of ground lower caldding layer and Mars underground water ice sheet.
Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (10)
1. a underground water-ice detection method, is characterized in that, comprising:
Steps A, arranges orthogonal transmitting-receiving multiplex antenna and receiving antenna;
Step B, by described transmitting-receiving multiplex antenna to the underground emission line polarimetric radar of detecting location ripple;
Step C, Real-Time Monitoring transmitting-receiving multiplex antenna and receiving antenna; And
Step D, if described transmitting-receiving multiplex antenna and receiving antenna receive echo simultaneously, shows that this echo is elliptically polarised wave, and detecting location is underground has water-ice.
2. underground water-ice detection method according to claim 1, is characterized in that, also comprises:
Step e, by first peak value of described echo and the mistiming between second peak value, obtains the first propagation delay τ of linear polarization radar wave in the underground top layer of detecting location
d1, by second peak value of described echo and the mistiming between the 3rd peak value, obtain the second propagation delay τ of linear polarization radar wave in the next top layer-water-ice layer in detecting location ground
d2;
Step F, by described the first propagation delay τ
d1with described the second propagation delay τ
d2, according to following formula, obtain martian surface cover thickness Z
1with Mars time top layer-water-ice layer thickness Z
2:
Wherein, c is the light velocity; ε
r1relative dielectric constant for the underground surface materials of detecting location; ε
r2for the specific inductive capacity of detecting location underground water ice sheet, ε
r2=3.15.
3. underground water-ice detection method according to claim 2, is characterized in that, the medium on the underground top layer of described detecting location is Irish touchstone, and its relative dielectric constant is ε
r1=7.1.
4. underground water-ice detection method according to claim 1, is characterized in that, described transmitting-receiving multiplex antenna and receiving antenna are a kind of in following antenna type: dipole antenna, Yagi antenna, log-periodic antenna, loop antenna and the antenna of falling V.
5. underground water-ice detection method according to claim 4, is characterized in that, described transmitting-receiving multiplex antenna and receiving antenna are dipole antenna.
6. underground water-ice detection method according to claim 1, is characterized in that, described transmitting-receiving multiplex antenna and receiving antenna are arranged on respectively two right opposites of a rectangular parallelepiped carrier or a hexahedron carrier.
7. underground water-ice detection method according to claim 6, is characterized in that, described transmitting-receiving multiplex antenna and receiving antenna are arranged on respectively two right opposites of a rectangular parallelepiped carrier, and is all 45° angle with corresponding face.
8. underground water-ice detection method according to claim 7, is characterized in that, the thickness of described rectangular parallelepiped carrier is 2m, and the distance of the center of described transmitting-receiving multiplex antenna and receiving antenna and the corresponding installed surface of described rectangular parallelepiped carrier is 1.75m.
9. according to the underground water-ice detection method described in any one in claim 1 to 7, it is characterized in that, for surveying the underground water-ice of the moon or Mars.
10. according to the underground water-ice detection method described in any one in claim 1 to 7, it is characterized in that, the transmission frequency of described linear polarization radar wave is UHF wave band and the following wave band of UHF wave band.
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Cited By (7)
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| CN103792586A (en) * | 2014-02-21 | 2014-05-14 | 中国科学院电子学研究所 | Underground ice layer detection method based on ice crystal anisotropy |
| WO2016095208A1 (en) * | 2014-12-19 | 2016-06-23 | 中国科学院电子学研究所 | Method and system for detecting geological structure of extraterrestrial solid celestial body by employing single transmitting and multi-receiving radar |
| CN106324578A (en) * | 2016-08-30 | 2017-01-11 | 中国水利水电科学研究院 | Integrated radar detection method for ice and water conditions |
| CN107678000A (en) * | 2016-08-02 | 2018-02-09 | 北京遥感设备研究所 | A kind of in-orbit celestial body underground detection radar system |
| CN109319105A (en) * | 2018-10-26 | 2019-02-12 | 武汉科技大学 | A kind of unmanned monitoring device of the mining underground space |
| CN109708250A (en) * | 2018-12-29 | 2019-05-03 | 珠海格力电器股份有限公司 | Frost layer detection method and device and household electrical appliance |
| CN109916449A (en) * | 2019-03-10 | 2019-06-21 | 黄河水利委员会黄河水利科学研究院 | A kind of fixed point ice thickness, water level integration continuous monitoring method |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103792586A (en) * | 2014-02-21 | 2014-05-14 | 中国科学院电子学研究所 | Underground ice layer detection method based on ice crystal anisotropy |
| WO2016095208A1 (en) * | 2014-12-19 | 2016-06-23 | 中国科学院电子学研究所 | Method and system for detecting geological structure of extraterrestrial solid celestial body by employing single transmitting and multi-receiving radar |
| US10649078B2 (en) | 2014-12-19 | 2020-05-12 | Institute Of Electronics, Chinese Academy Of Sciences | Method and system for detecting geological structure of an extraterrestrial solid planet by using a single-transmitter and multiple-receiver radar |
| CN107678000A (en) * | 2016-08-02 | 2018-02-09 | 北京遥感设备研究所 | A kind of in-orbit celestial body underground detection radar system |
| CN106324578A (en) * | 2016-08-30 | 2017-01-11 | 中国水利水电科学研究院 | Integrated radar detection method for ice and water conditions |
| CN109319105A (en) * | 2018-10-26 | 2019-02-12 | 武汉科技大学 | A kind of unmanned monitoring device of the mining underground space |
| CN109708250A (en) * | 2018-12-29 | 2019-05-03 | 珠海格力电器股份有限公司 | Frost layer detection method and device and household electrical appliance |
| CN109916449A (en) * | 2019-03-10 | 2019-06-21 | 黄河水利委员会黄河水利科学研究院 | A kind of fixed point ice thickness, water level integration continuous monitoring method |
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