US3719947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and device for detecting submerged bodies by means of megameter radio waves
Assignee: Individual
•
Filing: 1961-06-21
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Granted: 1973-03-06
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Expires: 1981-06-21
Abstract
Abstract A method of detecting bodies which are submerged into a liquid mass, by means of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, which consists in transmitting at the surface of the liquid mass megameter radio waves of the aforementioned character, simultaneously receiving in a plurality of receiving stations spaced from each other said emitted waves and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, determining at each receiving station the included angle formed by the lines joining said station to the wave emission and to the obstacle, measuring at the receiving stations for which said included angle is comprised between 60* and 120*, on the one hand, the phaseshift between the emitted and reflected waves and, on the other hand, the bearing angle formed by the direction for which the reception of the reflected waves is maximum and a stationary direction which is similar for all the receiving stations determining by the crossbearing method the geographical position of said obstacle by utilizing the thus measured bearing angles, and computing the depth of said obstacle from said measured phase-shift.
Inventors
- 👤 H Gutton
- 👤 J Hugon
- 👤 S Hugon
- 👤 M Augarde
- 👤 E Hugon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:14
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/06; G01S13/46
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
227 words
A method of detecting bodies which are submerged into a liquid mass, by means of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, which consists in transmitting at the surface of the liquid mass, megameter radio waves of the aforementioned character, sImultaneously receiving in a plurality of receiving stations spaced from each other said emitted waves and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, determining at each receiving station the included angle formed by the lines joining said station to the wave emission and to the obstacle, measuring at the receiving stations for which said included angle is comprised between 60* and 120*, on the one hand, the phase-shift between the emitted and reflected waves and, on the other hand, the bearing angle formed by the direction for which the reception of the reflected waves is maximum and a stationary direction which is similar for all the receiving stations, determining by the cross-bearing method the geographical position of said obstacle by utilizing the thus measured bearing angles, and computing the depth of said obstacle from said measured phase-shift.
Claim 2
Independent Claim
227 words
A method of detecting bodies which are submerged into a liquid mass, by means of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, which consists in transmitting at the surface of the liquid mass, megameter radio waves of the aforementioned character, sImultaneously receiving in a plurality of receiving stations spaced from each other said emitted waves and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, determining at each receiving station the included angle formed by the lines joining said station to the wave emission and to the obstacle, measuring at the receiving stations for which said included angle is comprised between 60* and 120*, on the one hand, the phase-shift between the emitted and reflected waves and, on the other hand, the bearing angle formed by the direction for which the reception of the reflected waves is maximum and a stationary direction which is similar for all the receiving stations, determining by the cross-bearing method the geographical position of said obstacle by utilizing the thus measured bearing angles, and computing the depth of said obstacle from said measured phase-shift.
Claim 3
Independent Claim
227 words
A method of detecting bodies which are submerged into a liquid mass, by means of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, which consists in transmitting at the surface of the liquid mass, megameter radio waves of the aforementioned character, sImultaneously receiving in a plurality of receiving stations spaced from each other said emitted waves and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, determining at each receiving station the included angle formed by the lines joining said station to the wave emission and to the obstacle, measuring at the receiving stations for which said included angle is comprised between 60* and 120*, on the one hand, the phase-shift between the emitted and reflected waves and, on the other hand, the bearing angle formed by the direction for which the reception of the reflected waves is maximum and a stationary direction which is similar for all the receiving stations, determining by the cross-bearing method the geographical position of said obstacle by utilizing the thus measured bearing angles, and computing the depth of said obstacle from said measured phase-shift.
Claim 4
Independent Claim
227 words
A method of detecting bodies which are submerged into a liquid mass, by means of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, which consists in transmitting at the surface of the liquid mass, megameter radio waves of the aforementioned character, sImultaneously receiving in a plurality of receiving stations spaced from each other said emitted waves and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, determining at each receiving station the included angle formed by the lines joining said station to the wave emission and to the obstacle, measuring at the receiving stations for which said included angle is comprised between 60* and 120*, on the one hand, the phase-shift between the emitted and reflected waves and, on the other hand, the bearing angle formed by the direction for which the reception of the reflected waves is maximum and a stationary direction which is similar for all the receiving stations, determining by the cross-bearing method the geographical position of said obstacle by utilizing the thus measured bearing angles, and computing the depth of said obstacle from said measured phase-shift.
Claim 5
Dependent Claim
14 words
A method according to claim 1, wherein several different frequencies are used for transmission.
Claim 6
Dependent Claim
304 words
A group for detecting bodies which are submerged into a liquid mass, by mass of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, comprising, in combination, at least one megameter wave-transmitting station consisting of a device for generating high power electrical energy at a very low frequency ranging from 1 to 100 c/s and of a submerged radiating system connected to said generating device; and a multiplicity of receiving stations spaced from each other and each one of which comprises two directive antenna loops the first one of which is orientated towards one transmitting station for receiving the waves emitted thereby while the second loop may be orientated in azimuth for simultaneously receiving the waves emitted by said transmitting station and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, means for orientating said loops, a depthwise-graduated phasemeter, a first electrical interconnecting means between said phasemeter and the first loop, means connected to said first electrical interconnecting means and generating an electromagnetic field of exactly opposite phase to that of the electromagnetic field generated by the submerged radiating system of said transmitting station and received by said first antenna loop, and a second electrical interconnecting means between said phasemeter and said antenna loop having means sensitive to said electromagnetic field of opposite phase for rendering null the electromotive force induced into said second loop by the electromagnetic field from said transmitting station when the lines joining said receiving station to said transmitting station and to said submerged obstacle form an included angle comprised between 60* and 120*.
Claim 7
Dependent Claim
304 words
A group for detecting bodies which are submerged into a liquid mass, by mass of megameter radio waves generating on the surface of said liquid mass a plurality of electric fields slightly inclined in their propagation direction and the horizontal component of which vertically propagates inwardly of said liquid mass, comprising, in combination, at least one megameter wave-transmitting station consisting of a device for generating high power electrical energy at a very low frequency ranging from 1 to 100 c/s and of a submerged radiating system connected to said generating device; and a multiplicity of receiving stations spaced from each other and each one of which comprises two directive antenna loops the first one of which is orientated towards one transmitting station for receiving the waves emitted thereby while the second loop may be orientated in azimuth for simultaneously receiving the waves emitted by said transmitting station and the waves obtained by reflection, on a submerged obstacle to be detected, of the vertically propagated horizontal component of the electric field existing in vertical alignment with said obstacle, means for orientating said loops, a depthwise-graduated phasemeter, a first electrical interconnecting means between said phasemeter and the first loop, means connected to said first electrical interconnecting means and generating an electromagnetic field of exactly opposite phase to that of the electromagnetic field generated by the submerged radiating system of said transmitting station and received by said first antenna loop, and a second electrical interconnecting means between said phasemeter and said antenna loop having means sensitive to said electromagnetic field of opposite phase for rendering null the electromotive force induced into said second loop by the electromagnetic field from said transmitting station when the lines joining said receiving station to said transmitting station and to said submerged obstacle form an included angle comprised between 60* and 120*.
Claim 8
Dependent Claim
16 words
A detection group according to claim 3, wherein at lest one transmitting station is on land.
Claim 9
Dependent Claim
16 words
A detection group according to claim 3, wherein at least one transmitting station is at sea.
Claim 10
Dependent Claim
16 words
A detection group according to claim 3, wherein at least one receiving station is on land.
Claim 11
Dependent Claim
16 words
A detection group according to claim 3, wherein at least one receiving station is at sea.
Claim 12
Dependent Claim
84 words
A detection group, according to claim 3, wherein the device for generating high power electrical energy at a very low frequency comprises a source of alternating current at very low frequency ranging from 1 to 100 c/s, and a transformer having a primary winding connected to said source and a secondary winding connected to the submerged radiating system, the said primary and secondary windings being designed to fully match the load rePresented by the impedance across said source of current and said radiating system.
Claim 13
Dependent Claim
83 words
A detection group according to claim 8, wherein the submerged radiating system comprises two metal floats spaced from each other by several kilometers, two fully-immersed electrodes of large size respectively supported by said floats, an insulated surface cable interconnecting one end of the secondary winding of the transformer and the electrode which is the closest to said transformer, and an insulated cable immersed at great depth in the liquid mass and interconnecting the other electrode and the other end of said secondary winding.
Claim 14
Dependent Claim
17 words
A detection group according to claim 9, wherein the second amplifier supplies a visualization and adjustment oscillograph.
Claim 15
Dependent Claim
20 words
A detection group according to claim 8, wherein the high-power energy generating device consists of a very-low-frequency high-power A.C. generator.
Claim 16
Dependent Claim
20 words
A detection group according to claim 8, wherein the high-power energy generating device consists of a very-low-frequency conventional valve oscillator.
Claim 17
Dependent Claim
23 words
A detection group according to claim 8, wherein the high-power energy generating device consists of an adjustable very-low-frequency modulator with high-power spark gaps.
Claim 18
Dependent Claim
148 words
A detection group according to claim 13, wherein the spark-gap modulator comprises two large and insulated main capacitors, a very-high-voltage D.C. source supplying current of very great intensity, two resistors respectively interconnecting said D.C. source and one end of said main capacitors, two ball-type spark-gaps respectively connected to said one end of said capacitors and having auxiliary spark-gaps acting as exciters, a control-pulse-generating electronic device connected to said auxiliary spark-gaps, a push-pull type transformer having a secondary winding connected to the submerged radiating system and a primary winding the ends of which are respectively connected to the other ends of said main capacitors while its center point is simultaneously connected to said D.C. source and to said auxiliary spark-gaps, and adjustable capacitors mounted in parallel on the half-windings of said primary winding for tuning the frequency of said transformer to the fundamental frequency given by the ball-type spark-gaps.
Claim 19
Dependent Claim
18 words
A detection group according to claim 3, wherein that the directive receiving antenna loops are ferrite-type antenna loops.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |