Note: Descriptions are shown in the official language in which they were submitted.
Sound transducer assembly, towed array sonar, winch, towboat
and deployment and retrieval method
FIELD OF THE INVENTION
[01] The invention relates to a sound transducer assembly for
receiving and/or transmitting waterborne sound signals, wherein
the sound transducer assembly has a first antenna with a
plurality of sound transducers and a first towing cable and
wherein the sound transducer assembly can be pulled in the water
by means of a towboat. Furthermore, the invention relates to a
towed array sonar for receiving and/or transmitting waterborne
sound signals, a winch for a towboat, a towboat and method for
deploying and/or retrieving a sound transducer assembly and/or
a towed array sonar and for receiving and/or transmitting
waterborne sound signals by means of a sound transducer assembly.
BACKGROUND
[02] Conventional towed array sonar systems usually have a
buoyancy-neutral reception antenna with hydrophones whose
running depth (towing depth) is set by means of the length and/or
the density of the deployed the towing cable and the velocity of
the towboat. In this context, the towing depth is always a
compromise between coverage of the water column and the maximum
horizontal location-determining range.
[03] Generally, the location-determining performance depends on
the profile of the speed of sound plotted against the depth of
the water. A disruption in the location-determining process can
occur as a result of sound anomalies arising at what is referred
to as a thermocline and/or convergence zone (junction between
water layers with different temperatures, pressures etc.). Owing
to the locally high refraction of the soundwaves, a thermocline
acts like a reflective horizontal separating wall for the sonar
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location-determining process, wherein the waterborne sound is
deflected to form a series of curves which curve to the surface
of the water and to the seafloor. With the exception of very
small angles, sonar systems can only determine locations on the
side of the thermocline on which they are located themselves.
Convergence zones arise, in particular, as a result of the fact
that sound beams are bent in the water in such way that blind
zones and zones with compression are produced. While the
compression effect permits on an individual basis relatively
large location-determining ranges, the blind zones or shadow
zones prevent continuous determination of locations.
[04] The thermocline problem can conventionally be avoided by
positioning two physically separate sonar systems respectively
above and below the thermocline. In a customary procedure, for
example a submarine selectively positions its towed array sonar
on the one side of the thermocline, while the submarine itself
remains with its sonar systems attached to the hull on the other
side of the thermocline, and performs location-determining
processes there. Therefore, it is also possible to avoid and/or
utilize blind zones or shadow zones which occur when there are
convergence phenomena.
[05] However, a surface vessel with its sonar systems mounted
fixedly on the hull has a higher intrinsic interference level
and is therefore limited in its application-determining
performance. For this reason, the procedure described above is
suitable only to a limited degree for surface craft. Also, in
contrast to submarines, with such surface craft it is not
possible to freely select the position which the sonar systems
mounted on the hull will assume in the water column.
[06] Surface craft can overcome this problem by having two
separate towed array sonar systems each with a separate winch,
wherein the respective sound transducers are then positioned
above and below the thermocline.
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[07] The large requirement for space and weight on board the
towboat are disadvantageous here. In addition there is the risk
of the large number of different towing cables becoming
intertwined and/or twisted, resulting in an increased risk of
drag loss. In addition, when a plurality of individual towed
array sonar systems are used there is a large amount of
expenditure on operator control and care.
SUMMARY
[08] The object of the invention is to improve the prior art.
[09] The object is achieved by means of a sound transducer
assembly for receiving and/or transmitting waterborne sound
signals, wherein the sound transducer assembly has a first
antenna with a plurality of sound transducers and a first towing
cable, and wherein the sound transducer assembly can be pulled
in the water by a towboat, and the first antenna and/or the first
towing cable have or has a coupling element or a plurality of
coupling elements, with the result that the first antenna and/or
the first towing cable can be reversibly connected to a second
antenna and/or a second towing cable.
[10] Some embodiments provide a sound transducer assembly for
receiving or transmitting waterborne sound signals, wherein the
sound transducer assembly has a first antenna with a plurality
of sound transducers and a first towing cable, and wherein the
sound transducer assembly is configured to be pulled in the water
by a towboat, wherein the first antenna, the first towing cable,
or both the first antenna and the first towing cable has or have
a coupling element or a plurality of coupling elements, with the
result that one or both of the first antenna and the first towing
cable are reversibly connectable in parallel to a second antenna
or a second towing cable; and wherein the sound transducer
assembly comprises the second antenna or the second towing cable,
with the result that when making a connection the first antenna
and the second antenna are spaced apart in the water when the
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coupling element opens or the plurality of the coupling elements
open.
[11] As result of the fact that two antennas can be connected
and disconnected again by means of coupling elements, they can
be used separately above and below a thermocline and provide
better coverage of the water column in the profile of the speed
of sound. It is therefore possible to carry out a location-
determining process, in particular, even with a highly
pronounced thermocline and/or convergence zone.
[12] Consequently, the coverage of the water column and the
maximum location-determining range can be optimized
simultaneously.
[13] Furthermore, the distance between the antennas can be set
by means of the number and/or the positions of the uncoupled
(opened) coupling elements and/or by means of the pulling speed
of the towboat.
[14] It is therefore possible both to optimize and to vary the
relative running depths of the antennas during the towing
process. Selectively opening individual coupling elements
permits the relative running depths of the antennas with respect
to one another to be varied. The distance between the antennas
in the water column is increased by opening coupling elements.
[15] A significant idea of the invention is that on board a
towboat a first antenna with a towing cable is connected via
coupling elements to a second antenna with a second towing cable,
and in the water some of the coupling elements are opened, with
the result that the two antennas become spatially separated and
are positioned at different running depths during the towing
process.
[16] As result, the connected antennas and towing cables are
handled jointly on board and require less space. There is
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therefore also no risk of the antennas and towing cables becoming
intertwined during the deployment and/or retrieval processes.
[17] The following terms are to be understood as follows:
[18] A "sound transducer assembly" is, in particular, an assembly
of a plurality of sound transducers for receiving and/or
transmitting waterborne sound signals. The sound transducer
assembly can be, particular, a trailing antenna and/or a towed
array sonar. In addition to an antenna or a plurality of
antennas, the sound transducer assembly also has, in particular,
a towing cable or a plurality of towing cables.
[19] The term "waterborne sound signals" is to be understood as
meaning, in particular, sound signals which are emitted and/or
received in the water.
[20] An "antenna" is, in particular, a technical device for
transmitting and/or receiving sound waves. An antenna is, in
particular, a liquid- and/or gel-filled hose sheath in which a
plurality of spaced apart electro-acoustic sound transducers are
arranged in a row. The antenna has, in particular, passive sound
transducers, such as, for example, hydrophones, which receive
waterborne sound signals. For the acoustic isolation with
respect to the towing cable (also referred to as pulling rope or
pulling cable), the antenna has, in particular, a damping module
or a plurality of damping modules. An antenna is, in particular,
a trailing antenna for extending the antenna, and, in particular,
an end piece can be arranged at the end which floats freely in
the water.
[21] A "sound transducer" is, in particular, a device for
transmitting and/or receiving acoustic underwater sound signals
such as is used in active and/or passive sonar systems. The sound
transducer receives underwater sound signals and converts them
into an electrical signal for further processing (receiver)
and/or converts an electrical signal into an acoustic signal,
Date Recue/Date Received 2020-06-23
wherein the latter is emitted (transmitter). For example,
hydrophones are used underwater as sound transducers, in order
to pick up underwater sound there. In this context, a hydrophone
converts the waterborne sound into an electrical variable
corresponding to the sound pressure. In the case of use
underwater, in particular a frequency range between
approximately 10Hz and 1MHz is used.
[22] A "towing cable" (also referred to as pulling cable or
pulling rope) is, in particular, a cable which sets a mechanical
process in train through pulling. In particular, the pulling
cable transmits the pulling force of the towboat to a trailing
antenna, with the result that the latter is towed in the water.
In order to transmit the towing force as far as possible without
delay or loss, the towing cable is, in particular, embodied in
a stretch-resistant fashion, for example as a solid wire. In
particular, the towing cable also has one or more lines for
exchanging data and/or for transmitting energy.
[23] A "coupling element" (also referred to as connecting
element) is, in particular, an element for the detachable,
reversible connection of two antennas and/or two towing cables
and/or an antenna and a towing cable. In particular, the coupling
element can be arranged on one antenna and connect to a second
antenna, or the coupling element can be arranged divided between
the two antennas. A coupling element can be, for example, a
sheath which is arranged in such a way that it can be slid onto
both antennas. In particular, the coupling element can have an
electromagnet, with the result to form a connection the
components of the electromagnetic coupling element which are
arranged, for example, on both antennas are attracted, and to
bring about disconnection of the antennas the two components of
the electromagnet on the two antennas repel one another. For
this purpose, for example coils through which current flows are
arranged on the coupling elements, assigned to one another, of
the two antennas. The coupling element can be arranged, in
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particular, as an elongated element along the antenna and/or the
towing cable, or a plurality of coupling elements can be arranged
at different positions at a predefined distance along the length
of the antenna and/or of the towing cable. In particular, the
coupling elements can be spaced equally apart along the antenna
and/or the towing cable or be at different distances. In
particular, the coupling elements of two antennas and/or towing
cables which are to be connected are arranged respectively
opposite one another on the same length, with the result that
the antennas and/or towing cables are connected in a flush
fashion and no loops are produced by lengths which are not
connected. The coupling elements can, in particular, assume
different shapes. In particular, a coupling element can be
arranged as a uniform ring about a trailing antenna and/or a
towing cable, and/or the coupling element itself has an irregular
shape. For example, the coupling element can be attached by
flanges to the direct connecting location and/or the coupling
elements can have more material and/or more density and/or a
different shape and/or a different orientation of the magnetic
field on the side opposite the connecting location, with the
result that this side of the antenna and/or of the towing cable
is pulled downward. In particular, the orientation of the antenna
and/or of the towing cable in the water can also be influenced
by the shape of the coupling element. In particular, the distance
between two antennas in the water column is increased by opening
coupling elements. In order to close the coupling elements, in
particular the towed array sonar is retrieved to such an extent
that the distance between the two antennas is reduced, with the
result that the coupling elements can be closed again.
[24] The term "reversibly connectable" is understood to mean, in
particular, that the connection of the antennas and/or of the
towing cables via a coupling element or a plurality of coupling
elements is reversible, with the result that the connection can
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be released again. In particular, the coupling elements can be
repeatedly connected and released.
[25] In a further development of the sound transducer assembly,
the coupling element has, or the coupling elements have, a
switching element, in particular an electromechanical switch.
[26] As a result, the coupling element or the coupling elements
can be opened or closed in a targeted fashion, with the result
that the antennas and/or the towing cables can connect to one
another or be released from one another. In addition, the
switching element can be actuated and switched by a controller.
Therefore, some of a plurality of coupling elements can be opened
and/or closed in a targeted fashion.
[27] Consequently, it is possible to open one or more coupling
elements in a targeted fashion by actuating the switching element
or switching elements after the deployment of the connected
antennas and towing cables into the water. The distance between
the antennas in the water can be set by the targeted opening of
the coupling element and/or coupling elements. Consequently, the
running depth and orientation of the antennas with respect to
one another can be set in conjunction with the pulling speed of
the towboat.
[28] A "switching element" is, in particular, a component which
establishes or disconnects an electrically conductive connection
(switching contact) by means of two electrically conductive
materials or a semiconductor element. As result, in particular
the switching element causes a coupling element to open or close,
with the result that two antennas and/or two towing cables and/or
an antenna and a towing cable are disconnected and/or connected.
In particular, the switching element can be actuated by a
controller, in particular by a control unit of a sonar system
and/or of the towboat.
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[29] In order to be able to use two antennas at different running
depths in the water, the sound transducer assembly has a second
antenna and/or a second towing cable, with the result that when
making a connection the first antenna and the second antenna can
be spaced apart in the water when the coupling element opens or
a plurality of the coupling elements open.
[30] As result, two antennas can be positioned in a targeted
fashion at different water depths and oriented horizontally. One
antenna can preferably be positioned above, and the second
antenna below, a thermocline, with the result that an
interference-free location-determining process is possible.
[31] It is in particular advantageous that in one embodiment
variant the direct arrangement of two antennas with differing
architecture, a thin long antenna (thin line array) and a
relatively thick, so-called triplet antenna or quadlet antenna,
relatively near one on top of the other in the water column,
permits, on the one hand, a spatial location-determining process
with a relatively large range and, on the other hand, a right-
left differentiation of the detection.
[32] Therefore, a relatively large range and/or better
resolution with two low-frequency antennas with different
designs can be achieved. The coupling elements are mounted here
on the antennas and towing cables in such a way that the
relatively thick and relatively short triplet antenna or quadlet
antenna is positioned centrally above the thin line array.
[33] In a further development of the sound transducer assembly,
the sound transducer assembly has a third antenna and/or third
towing cable and/or a fourth antenna and/or a fourth towing cable
and/or a fifth antenna and/or a fifth towing cable and/or further
antennas and/or further towing cables.
[34] Therefore, optimum "illumination" of the water column can
be achieved while avoiding blind zones and shadow zones, and at
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the same time the maximum horizontal location-determining range
can be improved. In addition, by using a plurality of antennas
with different designs and/or with different frequency ranges it
is also possible to improve the location-determining quality and
location-determining resolution further. Likewise, the
expenditure on operator control and monitoring during the
retrieval and deployment of a plurality of connected antennas
can be reduced further.
[35] In order to be able to carry out different location-
determining tasks, the antennas and/or the towing cables have
different lengths and/or different diameters.
[36] By virtue of different lengths, a relatively short antenna
with relatively short towing cable can be used at a relatively
shallow depth, and can be connected to a relatively long antenna
and/or the associated relatively long towing cables thereof.
[37] As result, it is possible to use both antennas of different
lengths and antennas with different sound transducers, with the
result that the antennas can cover different frequency ranges.
[38] So that the antennas can be positioned at different depths
from an averaged surface of the water when a coupling element is
open or a plurality of coupling elements are open, the towing
cables have different masses and/or different densities.
[39] As a result, in the case of buoyancy-neutral antennas it is
possible to set the distance between the antennas and their
positions in the water column directly by means of the mass
and/or the density of the towing cables. Consequently, a more
lightweight cable is used for an antenna which is to be oriented
in a relatively shallow water depth than for the further feeding
to the second antenna at a relatively large water depth. It is
also ensured in this way that the various antennas disconnect
when the coupling elements open. If a coupling element which
connects a heavy towing cable to a lightweight towing cable is
Date Recue/Date Received 2020-06-23
opened while the towboat is traveling, the water resistance acts
on the lightweight towing cable and the antenna connected thereto
as an opening torque.
[40] In a further embodiment of the sound transducer assembly,
the coupling elements have different shapes, in particular
asymmetrical shapes.
[41] As a result, intertwining of the antennas and towing cables
can be avoided, in particular, by virtue the fact that the local
mass distribution of each asymmetrical coupling element and/or
the mechanical influences of the asymmetrical shape and/or the
orientation of a magnetic field in the case of magnetic coupling
elements and/or the distance between coupling elements is used
in a targeted fashion. For this purpose, for example the coupling
elements have, on the sides lying opposite the connecting
locations, respectively more mass in the case of the first
antenna and less mass in the case of the second antenna, with
the result that owing to the masses these sides are always
oriented downward in the case of the first antenna and upward in
the case of the second antenna. In addition, the connection and
release of the coupling elements can be improved by means of an
asymmetrical shape. In addition, this asymmetry can, where
appropriate, compensate different diameters of the towing
cables.
[42] So that the connected towing line can be wound on and/or
unwound from a winch, particular a single winch drum, of a
towboat, the antennas and the towing cables form a connected
towing line when the coupling element is closed or the coupling
elements are closed.
[43] As a result, it is possible to achieve a saving in terms of
space and weight on board the towboat, and expenditure on
operator control can be reduced. In addition, the individual
towing cables can be made thinner, since the towing occurs at
the connected part of all the towing cables.
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[44] A "winch" is, in particular, a device with which a trailing
antenna and/or a plurality of trailing antennas and/or a towing
cable and/or a plurality of towing cables and/or a connected
towing line can be deployed into the water and/or retrieved from
the water from a towboat. In particular, a winch has a rotatable
winch drum for winding on and/or unwinding a connected towing
line and/or an antenna and/or a towing cable.
[45] A "winch drum" (also referred to as a double-flanged spool
or cable drum) is, in particular, a spool or reel which material
with an, in particular, round cross-section is rolled onto and/or
unrolled from. In particular, the spool or the reel has, on the
two outer sides, edges which limit the spreading out of the
rolled material. In particular a connected towing line, an
antenna, a towed array seminar and/or a towing cable is rolled
onto and/or unrolled from a winch drum.
[46] In a further aspect of the invention, the object is achieved
by means of a towed array sonar for receiving and/or transmitting
waterborne sound signals, wherein the towed array sonar has a
sound transducer assembly as described above.
[47] As a result, a space-saving and weight-saving user-friendly
towed array sonar with two or more antennas which can be towed
at various water depths can be made available. This permits a
high-quality location-determining process of waterborne sound
sources even when there is a thermocline and/or convergence zone.
[48] A "towed array sonar" is, in particular, a device for
determining the location of objects in space and underwater by
means of emitted and/or received sound pulses. In particular, a
towed array sonar is used for seismic measurement of the sea
floor and/or for determining the location of objects and
watercraft underwater. For this purpose, the towed array sonar
is, in particular, immersed by a towboat and pulled through the
water on a towing cable. A towed array sonar can be an active
sonar system which itself emits sound signals and receives the
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reflected signals thereof, or a passive sonar which has only a
receiver part. A towed array sonar can also be, in particular,
part of a bistatic sonar in which the transmitter is located on
a different platform or in a different antenna than the receiver.
In particular, the towed array sonar is assigned a plurality of
antennas and/or towing cables which can be connected via coupling
elements.
[49] In a further aspect, the object is achieved by means of a
winch for a towboat, wherein a sound transducer assembly as
described above and/or a towed array sonar as described above
can be wound on and/or unwound by means of the winch.
[50] As result, a space-saving winch for winding on and/or
unwinding antennas and towing cables which are connected to a
towing line is made available. Therefore, the expenditure on
operator control and care during the deployment and retrieval
are reduced.
[51] In a further embodiment of the winch, the winch is assigned
a guide device, with the result that during the deployment
process the antennas and/or the respectively associated towing
cables are placed at a spatial distance from one another and/or
during the retrieval process they are moved into spatial
proximity to one another.
[52] Therefore, a guide device assists the connection and/or
disconnection of the coupling elements of the antennas and/or
towing cables. In particular, the guiding of the antennas and
towing cables with respect to one another is important in the
case of electromagnetic coupling elements, so that they can
attract one another.
[53] A "guide device" is, in particular, a device which moves
antennas and/or towing cables into spatial proximity with
respect to one another and/or to a spatial distance from one
another. In this context, the guide device can be arranged
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directly on the winch or in a freely positionable fashion on
and/or at the ship or boat. For example, the guide device can be
on the outside of the side of the ship or boat. A guide device
is, in particular, a guide funnel, guiding rails and/or guiding
panels.
[54] In a further aspect, the object is achieved by a towboat,
wherein the towboat has a sound transducer assembly as described
above and/or a towed array sonar as described above and/or a
winch as described above.
[55] As a result, a towboat can be made available for high-
quality location determination, which towboat can have various
types of sound transducer assemblies and/or a towed array sonar
for different running depths. In addition, the towboat has a
relatively large reserve in terms of space and/or weight.
[56] In a further aspect of the invention, the object is achieved
by means of a method for deploying and/or retrieving a sound
transducer assembly and/or a towed array sonar and for receiving
and/or transmitting waterborne sound signals by means of a sound
transducer assembly as described above and/or a towed array sonar
as described above and/or a winch as described above, and/or a
towboat as described above, comprising the following steps:
- deploying the sound transducer assembly and/or the towed
array sonar in a connected towing line into the water by
means of the winch of the towboat,
- switching the coupling element or coupling elements, with
the result that the coupling element opens or the coupling
elements open,
- spacing apart from one another the first antenna and/or a
part of the first towing cable and the second antenna and/or
a part of the second towing cable on the basis of the opened
coupling element and/or the opened coupling elements,
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- horizontally orienting the first antenna and the second
antenna at different depths from an average surface of the
water when towing the sound transducer assembly and/or the
towed array sonar with a connected part of the first towing
cable and of the second towing cable by means of the
towboat,
- transmitting and/or receiving a waterborne sound signal
and/or a plurality of waterborne sound signals by means of
the first antenna and/or of the second antenna, with the
result that the waterborne sound signal or the waterborne
sound signals can be used free of interference, in
particular by a thermocline and/or a convergence zone, for
a location-determining process,
- spatially approximating the first antenna and/or the
uncoupled part of the first towing cable and the second
antenna and/or the uncoupled part of the second towing cable
during the retrieval of the sound transducer assembly
and/or of the towed array sonar by means of the winch of
the towboat,
- switching the coupling element or coupling elements, with
the result that the coupling element closes or the coupling
elements close,
- connecting the first antenna and/or the uncoupled part of
the first towing cable and the second antenna and/or the
uncoupled part of the second towing cable to form a towing
line on the basis of the closed coupling element or the
closed coupling elements, and
- winding the connected towing line onto a winch drum of the
winch of the towboat.
[57] As result, a reliable method for deploying and retrieving
a sound transducer assembly and/or a towed array sonar with a
Date Recue/Date Received 2020-06-23
plurality of antennas and a precise method for receiving and/or
transmitting waterborne sound signals and for determining
locations even in the case of interference by, for example, a
thermocline can be made available.
BRIEF DESCRIPTION OF THE FIGURES
[58] Furthermore, the invention will be explained in more detail
on the basis of exemplary embodiments. In the drawings:
Figure 1 shows a highly schematic illustration of a towboat with
a towed array sonar, und
Figure 2 shows a highly schematic sectional illustration of a
winch with a guide funnel.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[59] A towboat 101 is traveling on the sea and has a towed array
sonar 102. The towed array sonar 102 has a first antenna 103
with a first towing cable 104 and a second antenna 106 with a
second towing cable 107. The first antenna 103 has seven
different reception modules 105, and the second antenna 106 has
ten reception modules 108. The first antenna 103 and the second
antenna 106 are embodied in a buoyancy-neutral fashion, while
the first towing cable 104 is lighter in weight than the second
towing cable 107.
[60] The first antenna 103 is oriented horizontally at a depth
of 50m and the second antenna 106 at a depth of 250m. The first
antenna 103 is located above, and the second antenna 106 is
located below, a thermocline 112. Owing to the thermocline 112,
a profile 113 of the speed of sound is curved both toward the
surface of the water 111 and toward the sea floor.
[61] The first antenna 103 and the first towing cable 104 as
well as the second towing cable 107 have electromagnetic
couplings 109. The electromagnetic couplings 109 are open at the
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first antenna 103, part of the first towing cable 104 and part
of the second towing cable 107. The other electromagnetic
couplings 109 of the first towing cable 104 and the second towing
cable 107 are closed and form a connected part of the first and
second towing cables 110. The towed array sonar 102 is connected
to the connected part of the first and of the second towing
cables 110 to a winch 114 of the towboat 101.
[62] The winch 114 is arranged in a frame 221. The winch 114 has
a rotatable drum 222 with the axis of rotation 226. A motor 227
is arranged laterally on the frame 221. A guide carriage 224 and
a guide funnel 223 are arranged at the top of the frame 221.
[63] The following working steps are implemented with the towboat
101 and the towed array sonar 102:
[64] The first antenna 103, the first towing cable 104, the
second antenna 106 and the second towing cable 107 are placed as
a connected towing line 225 in the water by means of the winch
114 of the towboat 101 when the electromagnetic couplings 109
are closed.
[65] As soon as the connected towing line 225 is deployed in the
water, the electromagnetic couplings 109 are switched. As a
result, the electromagnetic couplings 109 open, and owing to the
different densities of the first towing cable 104 and of the
second towing cable 107 and the pulling speed of the towboat
101, which tows the first antenna 103 and the second antenna 106
at the connected part of the first and second towing cables 110,
the first antenna 103 and the second antenna 106 are oriented
horizontally at the different water depths of 50m and 250m from
the averaged surface of the water 111. As result, the first
antenna 103 is located above, and the second antenna 106 below,
the thermocline 112.
[66] Both antennas 103 and 106 receive waterborne sound signals
by means of their reception modules 105 and 108. In the process,
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the first antenna 103 covers the region above the thermocline
112, and the second antenna 106 covers the region below the
thermocline 112. The waterborne sound signals are evaluated on
board the towboat 101 and are used for the determination of the
location of an unknown submarine.
[67] After the conclusion of the mission, the towed array sonar
102 is retrieved by means of the winch 114 by firstly winding on
the connected part of the first and second towing cables 110 by
means of the rotational movement of the drum 222, driven by the
motor 227. As soon as the lower, disconnected parts of the first
towing cable 104 and of the second towing cable 107 with the
opened electromagnetic couplings 109 move into the region of the
guide funnel 223 of the winch 114 and as a result are placed in
spatial proximity, the electromagnetic couplings 109 are
switched and they close in order to connect the disconnected
parts of the first towing cable 104 and of the second towing
cable 107. Then, the relatively short antenna 103 is also
connected in the region of the guide funnel 223 to the remaining
disconnected part of the second towing cable 107 and subsequently
to a part of the second antenna 106 by closing the
electromagnetic couplings 109. As a result, a single connected
towing line 225 is formed which is wound onto the drum 222 of
the winch 214.
18
Date Recue/Date Received 2020-06-23
List of reference numerals
101 Towboat
102 Towed array sonar
103 First antenna
104 First towing cable
105 Reception modules
106 Second antenna
107 Second towing cable
108 Reception modules
109 Electromagnetic couplings
110 Connected part of the first and second
towing cables
111 Surface of the water
112 Thermocline
113 Profile of the speed of sound
114 Winch
221 Frame
222 Drum
223 Guide funnel
224 Guide carriage
225 Connected towing line
226 Axis of rotation
227 Motor
19
Date Recue/Date Received 2020-06-23
