Sonar receiver assembly
Patent Information
- Application Number
- EP2023707279
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-03-04
- Filing Date
- 2023-02-17
- Publication Date
- 2025-01-08
Smart Images
Figure 1.1
Abstract
Description
[0001] Water sound reception arrangement
[0002] Description
[0003] The invention relates to a water sound receiving arrangement with a water sound receiver and a damping layer arranged behind the water sound receiver for reducing the influence of disturbing sound on the (total) water sound received by the water sound receiver, which includes disturbing sound and useful sound.
[0004] Waterborne sound receiver assemblies typically comprise a waterborne sound transducer, a hard reflector, and a soft damping layer. These are stacked in this order and typically directly mechanically connected to each other. This makes it possible to achieve a good signal-to-noise ratio within a small installation space for the waterborne sound receiver assembly. The hard reflector amplifies the wanted signal impinging on the waterborne sound transducer from the front compared to a free-field arrangement of the waterborne sound transducer. The damping layer attenuates any interfering signals impinging on the waterborne sound transducer from behind.
[0005] However, this principle doesn't work across the entire frequency range. It has been shown that at low frequencies, not only is there no amplification from the hard reflector, but the desired signal is actually attenuated. This means that the waterborne sound transducer receives significantly less sound energy from the waterborne sound compared to its use in a free field.
[0006] The object of the present invention is therefore to create an improved concept for a water sound receiving arrangement.
[0007] This object is achieved by the subject matter of the independent patent claims. Further advantageous embodiments are the subject matter of the dependent patent claims. Exemplary embodiments show a water sound receiving arrangement with a water sound receiver and a water sound silencer. The water sound receiver converts incoming water sound into an electrical signal corresponding to the sound pressure. The water sound silencer has a sound-damping layer that includes or consists of a sound-soft material in order to reflect incoming water sound in a dampened manner. This means that the incoming water sound loses a significant amount of energy before it is reflected again. The energy loss can amount to more than 10%, more than 20%, or more than 30% of the energy of the water sound upon impacting the water sound silencer.The water silencer is typically located primarily behind the water sound receiver, especially from the direction of the main sound incidence. This reduces reflection of incoming useful sound. Furthermore, disturbing sound from the direction of the water silencer cannot reach the water sound receiver, or only in an attenuated form.
[0008] The main sound incidence direction is the direction for whose reception of the wanted signal the underwater sound receiving arrangement is optimized. This is typically the horizontal when the underwater sound transducer is used in its intended orientation, i.e. in particular when installed in a support platform, for example a watercraft. A foam, for example, is used as a sound-soft material. The foam can comprise or consist of a polyurethane (PUR) elastomer, in particular a closed-cell one. The foam preferably has any selection (or all) of the following properties: a lower speed of sound than the speed of sound in water, a lower density than the density of water, and an absorption coefficient (defined as the ratio, i.e. quotient, of the absorbed sound intensity to the total incident sound intensity) at 1000 Hz of greater than 0.8, preferably greater than 0.85, particularly preferably greater than 0.9. The water silencer has a curvature to create a cavity between the water sound receiver and the water silencer.
[0009] It has been shown that the cavity between the waterborne sound receiver and the waterborne sound attenuator prevents, or at least minimizes, the drop in the waterborne sound level at low frequencies. Depending on the design of the waterborne sound receiver assembly, a low frequency is considered to be a frequency below 2 kHz or a frequency below 1 kHz. Nevertheless, the waterborne sound attenuator meets the requirements for reducing background noise. For incident sound, the attenuation effect is enhanced by the fact that the sound is typically softly reflected several times by the curvature before being reflected back to the waterborne sound receiver.
[0010] In exemplary embodiments, the water sound absorber has a sound wave breaking element that extends from the curvature into the cavity. The sound wave breaking element can be designed as a point or a narrow edge at which the incoming water sound is not reflected or is only minimally reflected. The sound wave breaking element advantageously also has the sound damping layer. The sound wave breaking element is also referred to as a sound wave breaker for short. The sound wave breaking element increases the probability that incoming useful sound will be reflected multiple times before it hits the water sound receiver again. Diffraction effects also occur at the edges. These are frequency-dependent, i.e. wavelength-dependent, and can be taken into account in the geometry and positioning of the sound wave breaking element.For example, a distance between two sound wave breaking elements is chosen such that it is smaller than half the design frequency of the water sound receiving arrangement.
[0011] Embodiments show the waterborne sound receiving arrangement, wherein the sound damping layer lines the waterborne sound absorber such that the sound damping layer delimits the cavity. In this case, the waterborne sound absorber can have, on a side facing away from the cavity, a substantially sound-transparent carrier layer on which the sound damping layer is arranged. Substantially sound-transparent means that, for example, the sound transmission loss of the carrier layer is less than 1 dB. A GRP (glass fiber reinforced plastic) plate can be used as the carrier layer. Accordingly, the curvature of the carrier layer can be lined (in particular completely) with the sound damping layer on the inside, i.e. in the direction of the waterborne sound receiver. In contrast, the sound damping layer can have a sound transmission loss of more than -40 dB, i.e. a value <-40 dB.This applies to sound waves almost independently of their direction of incidence.
[0012] In an embodiment with the sound wave breaking element, the sound wave breaking element can preferably also be covered with the sound damping layer. The essentially sound-transparent carrier layer prevents background noise incident on the water sound receiving arrangement from the direction of the water sound damper from being reflected excessively hard by the carrier layer. Rather, the background noise predominantly passes through the carrier layer and is absorbed by the sound damping layer and reflected softly. As a result, from the perspective of the water sound receiver, no excessive noise level from background noise builds up behind the water sound damper. This combination of carrier layer and sound damping layer prevents any background noise from reaching the water sound receiver.
[0013] In exemplary embodiments, the water sound absorber either has no mechanical connection between the water sound receiver and the water sound absorber, or a mechanical connection between the water sound absorber and the water sound receiver provides acoustic decoupling. Thus, any excitation of the water sound absorber cannot be transmitted to the water sound receiver.
[0014] In exemplary embodiments, the underwater sound receiver is one of a plurality of underwater sound receivers. This means that the plurality of underwater sound receivers form an antenna. The antenna makes it possible, for example, to enable directional determination of noise in incoming underwater sound. This means that the direction from which a noise hits the underwater sound receivers can be determined mathematically. The underwater sound receivers of the plurality of underwater sound receivers are arranged linearly or in a planar manner. With a linear antenna, directional determination can be carried out in one plane, typically the horizontal. Using a planar antenna, directional determination can be carried out in both relevant planes (horizontal and vertical).A linear antenna can also appear flat, for example if a rod-shaped sensory material is used as the water sound receiver or if different sensory materials are connected to a so-called stave, e.g. in the shape of a rod, from which only a sum signal and no individual signals from the sensory materials of the stave can be picked up. The cavity of the water sound damper is arranged behind the water sound receivers of the plurality of water sound receivers. This means that the water sound damper provides a common cavity for several water sound receivers, optionally for the entire antenna. This reduces the material used, for example, and thus the weight of the water sound receiving arrangement. Furthermore, a uniform acoustic "background" is created for the entire antenna - independent of the other installations around and behind the water sound receiving arrangement.Due to the uniform acoustic background, for example, a uniform interference signal reduction can be carried out for the waterborne sound transducers without having to carry out individual interference signal reduction for each waterborne sound transducer.
[0015] In exemplary embodiments, the cavity, starting from the underwater sound receiver, has a maximum depth corresponding to at least half the wavelength of a lower limit frequency of the underwater sound receiving arrangement. This means that at a lower limit frequency of 1000 Hz, which corresponds to a wavelength of approximately 1500 mm in water, the cavity can have a maximum depth of at least 750 mm. At this minimum depth, the frequency-dependent negative effects of a stack comprising a underwater sound transducer, a hard reflector, and a soft damping layer described above no longer occur. The lower limit frequency can be found, for example, in the data sheet of the underwater sound receiving arrangement. The lower limit frequency can be defined as the frequency that experiences an attenuation of -3 dB compared to a design frequency of the underwater sound receiving arrangement. The maximum depth can be defined as a perpendicular (i.e.Normal) on the sound-damping element up to the waterborne sound transducer (or one waterborne sound transducer of the plurality of waterborne sound transducers) can be measured. This is particularly possible if the waterborne sound receivers are arranged on a vertical plane in front of the sound-damping layer. Alternatively, for example, if the waterborne sound receiver arrangement is arranged at an angle in front of the sound-damping layer, the distance in the (main) sound incidence direction can also be used as the distance measure.
[0016] In further embodiments, the underwater sound receiving arrangement is devoid of a underwater sound reflector. Such an arrangement is particularly advantageous when the underwater sound sensitivity of the underwater sound receiving arrangement has a low inherent noise. Furthermore, this arrangement is advantageous when a support platform of the underwater sound receiving arrangement, for example a watercraft on which the underwater sound receiving arrangement is arranged, does not exhibit excessive inherent noise. The influence of the inherent noise on the underwater sound receivers can then be reliably reduced using the described underwater sound receiving arrangement. If the interference is reduced to such an extent that useful signals can be reliably detected even without a underwater sound reflector, omitting the underwater sound reflector has no negative effects.
[0017] Negative effects would only occur if the vessel exhibited excessive inherent noise, which even the underwater sound receiver system could not sufficiently reduce. However, especially in the case of an underwater vehicle, the entire design would then have to be questioned, as high inherent noise also increases the probability of detection by third parties using passive sonar. The lower weight of the underwater sound receiver system and the lower reflectivity of underwater sound also have a positive effect. The lower reflectivity of underwater sound has a particularly positive effect on the vessel's own signature (or the signature of the carrier platform). The lower the signature, the lower the probability of detection by third parties using active sonar.
[0018] In exemplary embodiments, it is further shown that a water sound reflector is arranged adjacent to the water sound receiver, which is designed to amplify the sound waves impinging on the water sound transducer. This is particularly advantageous when interference signals become too loud and thus a desired or predetermined signal-to-noise ratio (SNR) can no longer be maintained. By means of the water sound reflector, a useful signal can then be amplified and thus the SNR improved. However, attention is required if it is likely that the water sound receiving arrangement could be exposed to a shock, for example an (underwater) explosion, e.g. from a mine. In this case, a water sound reflector, which is inherently reverberant, introduces a considerable shock load into the overall system due to the pressure wave.
[0019] To mitigate the resulting energy acting on the support platform compared to the energy of the shock wave, in exemplary embodiments, the waterborne sound reflector can be mechanically connected to the waterborne sound damper, wherein the mechanical connection comprises a shock mount for the waterborne sound reflector. A shock mount can be considered a mechanical attachment that absorbs the energy of the shock wave but transfers only a small portion of it to the waterborne sound reflector and thus to the support platform. This is achieved, for example, by a spring or robust foam.
[0020] For example, the waterborne sound reflector is connected to the waterborne sound damper via a moment joint to enable shock support of the waterborne sound reflector. A moment joint is characterized by the fact that it induces a defined natural vibration mode of the system, in which the system primarily responds (bending mode). Energy can be removed from this natural vibration mode through damping, thereby reducing the shock response.
[0021] In addition to or as an alternative to the moment joint, the water sound damper can form a spring element to which the water sound reflector is mechanically connected, wherein the spring element enables shock mounting of the water sound reflector. The spring element can be designed as a flexible tongue that projects from the water sound damper into the cavity. The tongue typically has a different angle to the water sound receiver and / or the water sound reflector than the sound wave breaking element(s). Starting from the spring element, another sound wave breaking element can project into the cavity. The another sound wave breaking element is preferably arranged parallel to one of the previously described sound wave breaking elements, which projects from the water sound damper into the cavity.
[0022] In further embodiments, the sound receiver of the waterborne sound receiving arrangement has a linear extension or an extension in a plane. The waterborne sound receiver has an inclination relative to the sound wave breaking element. The sound wave breaking element is typically arranged parallel to a main sound incidence direction. This ensures that incoming waterborne sound is reflected by the waterborne sound receivers or a waterborne sound reflector arranged parallel to them in the direction of the transmitter.
[0023] Furthermore, an underwater vehicle with the underwater sound reception arrangement is disclosed. The underwater vehicle comprises a first hull defining a pressure hull and a second hull surrounding the first hull. The second hull is arranged at a distance from the first hull, such that a gap is formed between the first and second hulls. Such an underwater vehicle is also referred to as a double-hull underwater vehicle or double-hull boat. Typically, the gap between the first and second hulls also forms a space that is freely flooded or can be designed as a pressure hull. Advantageously, the gap is filled with the seawater surrounding the underwater vehicle.
[0024] The underwater sound receiver assembly is located in the space between the first hull and the second hull. This provides a further advantage in that the underwater sound does not need to pass into another medium to reach the underwater sound receivers. It only needs to pass through the second hull. This means that the direction of incidence is neither changed nor is there any significant attenuation of the underwater sound. The space between the two hulls makes it possible to integrate the underwater sound receiver assembly with the curved underwater sound silencer into the underwater vehicle. Previously, the underwater sound receiver assembly was screwed to the outside of the underwater vehicle. However, the proposed underwater sound receiver assembly would take up too much space, so in this case the familiar sandwich or stacked arrangement consisting of the underwater sound receiver, underwater sound reflector, and underwater sound silencer (without curvature) is preferable.
[0025] In exemplary embodiments, the second hull comprises a plurality of interconnected, planar hull elements such that a sonar cross-sectional area of the underwater vehicle is minimized. The sonar cross-sectional area is also referred to as the signature. Such an underwater vehicle is also referred to as a "stealth" or "invisible" underwater vehicle. The planar hull elements are preferably designed to reflect sound waves as little as possible. This means that the planar hull elements are designed to be as acoustically soft as possible. Furthermore, the planar hull elements are arranged such that incoming water sound is predominantly reflected in a direction other than the direction of incidence, thus making location using active sonar more difficult. For example, the water sound can be predominantly reflected in the direction of the seabed.This can dampen incident water sound, making it more difficult to receive reflected water sound and, in addition, the direction from which the reflection comes can hardly be determined from the perspective of passive sonar.
[0026] In this embodiment, the water sound receiving arrangement preferably has the absence of a water sound reflector.
[0027] The waterborne sound receiver or waterborne sound receivers of the plurality of waterborne sound receivers are preferably arranged parallel to a planar shell element of the plurality of planar shell elements. This means that the waterborne sound receiver preferably has a linear or planar extension, or the waterborne sound receivers form a linear or planar antenna.
[0028] Preferably, the waterborne sound receiver(s) is / are arranged behind the parallel, flat shell element. This means that the predominant waterborne sound enters the space occupied by the waterborne sound receiver arrangement through the parallel, flat shell element. Advantageously, the parallel, flat shell element lacks a soft sound-damping layer. Rather, it is advantageous for the flat shell element to have a similar waterborne sound impedance to the surrounding water. Preferred embodiments of the present invention are explained below with reference to the accompanying drawings. They show:
[0029] Fig. 1: in Fig. 1a, Fig. 1b and Fig. 1c three different embodiments of a water sound receiving arrangement in a schematic sectional view;
[0030] Fig. 2: a schematic perspective view of the embodiment according to Fig. 1 b;
[0031] Fig. 3: a schematic cross-sectional view of an underwater vehicle with two hulls, with the underwater sound receiving arrangement arranged between the two hulls
[0032] Before exemplary embodiments of the present invention are explained in more detail below with reference to the drawings, it is pointed out that identical, functionally equivalent or equivalent elements, objects and / or structures in the different figures are provided with the same reference numerals, so that the description of these elements shown in different exemplary embodiments is interchangeable or can be applied to one another.
[0033] Fig. 1a shows a sectional view of a waterborne sound receiving arrangement 20. The waterborne sound receiving arrangement 20 comprises a waterborne sound receiver 22 and a waterborne sound dampener 24 with a sound-damping layer 26. The waterborne sound receiver 22 converts incoming waterborne sound into an electrical signal corresponding to the sound pressure. The waterborne sound dampener 24 reflects incoming waterborne sound, dampened by the sound-damping layer 26. Furthermore, the waterborne sound dampener has a curvature to create a cavity 28 between the waterborne sound receiver 22 and the waterborne sound dampener 24. Optionally, the waterborne sound dampener has a carrier layer 30. The sound-damping layer 26 is applied to the carrier layer 30, particularly if the sound-damping layer would otherwise not be dimensionally stable.The curved shape of the water sound absorber and the cavity 28 allow water sound that enters the cavity through (or past) the water sound receiver 22 to be softly reflected several times by the sound-damping layer 26, thus losing energy before the water sound possibly impacts the water sound receiver 22 again. This noticeably improves the signal-to-noise ratio.
[0034] Fig. 1b shows a sectional view of the waterborne sound receiver assembly 20 in a further exemplary embodiment. Three sound wave breaking elements 32 are also shown here. These are formed from the sound damping layer 26, which is optionally applied to the carrier layer 30. The sound wave breaking elements 32 ensure a further reduction of the sound energy of the waterborne sound in the cavity before the waterborne sound strikes the waterborne sound receiver 22 again.
[0035] Fig. 1c shows a sectional view of the waterborne sound receiving arrangement 20 in a further exemplary embodiment. Here, the waterborne sound damper has two spring elements 34, 34'. The waterborne sound receiver(s) 22 can be attached to the spring elements, which is not shown in the figure. Instead, the figure shows an optional waterborne sound reflector 36, which is arranged behind the waterborne sound receiver(s) 22. Advantageously, the waterborne sound reflector 36 can be (mechanically) connected to the spring elements. The spring elements can then form a shock mount for the waterborne sound reflector or at least form one component of a shock mount.
[0036] Furthermore, Fig. 1c discloses that, in addition to the sound wave breaking element 32, which extends from the curvature of the water sound absorber 24, two further sound wave breaking elements 32' are provided, particularly symmetrically, extending from the spring elements. For example, the spring element 34' together with the sound wave breaking element 32' forms a virtually closed space 40 through which water sound can only enter and exit through a small opening 38. Once it enters this space 40, the water sound will most likely lose a large portion of its energy and will not re-impact the water sound receiver 22 or the water sound reflector 36. The sound wave breaking element 32 further promotes the accumulation of water sound in the space 40.
[0037] Fig. 2 shows the embodiment according to Fig. 1b in a schematic perspective view. The dimensions of the individual elements are visible here. In particular, a planar antenna 22 is shown schematically. This is shown in a highly simplified manner and includes, for example, a plurality of rod-shaped waterborne sound receivers.
[0038] Fig. 3 shows a schematic sectional view of an underwater vehicle 42, in particular a submarine. The underwater vehicle 42 has a first hull 44 and a second hull 46. The first hull 44 delimits a pressure hull 48 of the underwater vehicle 42. The second hull 46 encloses the first hull 44. Furthermore, the second hull 46 is arranged at a distance from the first hull 44, so that an intermediate space 50 is formed between the first and second hulls 44, 46. The intermediate space 50 can also be designed as a pressure hull. The intermediate space 50 can be flooded with water, preferably the seawater surrounding the underwater vehicle. It is further shown that the second hull 46 of the underwater vehicle 42 optionally comprises a plurality of interconnected, flat hull elements 52a, 52b, 52c.
[0039] The waterborne sound receiving arrangement 20 is arranged in the intermediate space 48. An optional second waterborne sound receiving arrangement 20' is also shown. The waterborne sound receiver 22 of the waterborne sound receiving arrangement 20 is arranged parallel to the planar shell element 52b. A waterborne sound reflector (not shown) would also be arranged parallel to the planar shell element 52b. Nevertheless, the sound wave breaking elements 32 are aligned in the main direction of incidence of the waterborne sound. This means that the sound wave breaking elements do not point perpendicularly to the waterborne sound receiver(s) or the waterborne sound reflector, but rather form an angle other than 90° thereto. This means that the waterborne sound receiver 22 is inclined relative to the sound wave breaking element 32. The waterborne sound receiving arrangement is then no longer mirror-symmetrical in a plane that deviates from the plane of the drawing. This meansAll planes that do not perpendicularly intersect the pressure hull 48 cannot form a mirror plane for the underwater sound receiving arrangement 20. However, the underwater vehicle optionally has a mirror plane of symmetry. This plane runs from front to back and from top to bottom, centering the underwater vehicle 42. This means, with reference to Fig. 3, one dimension of the plane extends into the image plane, and a second dimension of the plane runs from top to bottom.
[0040] The disclosed (water) sound transducers are designed for use underwater, particularly in the sea. The sound transducers can convert water sound into an electrical signal (e.g., voltage or current) corresponding to the sound pressure, the water sound signal. Furthermore, it is possible for the sound transducers to convert an applied electrical voltage into water sound. The sound transducers can therefore be used as water sound receivers and / or as water sound transmitters. The sound transducers can comprise a piezoelectric material, such as a piezoceramic, as the sensor material. The sound transducers can be used for (active and / or passive) sonar (sound navigation and ranging, dl: sound navigation and ranging). The sound transducers are preferably not suitable for medical applications and are not used for medical applications.
[0041] Although some aspects have been described in connection with a device, it is understood that these aspects also represent a description of the corresponding (e.g., manufacturing) process, so that a block or component of a device is also to be understood as a corresponding process step or as a feature of a process step. Analogously, aspects described in connection with or as a process step also represent a description of a corresponding block, detail, or feature of a corresponding device.
[0042] The above-described embodiments are merely illustrative of the principles of the present invention. It is understood that modifications and variations of the arrangements and details described herein will be apparent to others skilled in the art. Therefore, it is intended that the invention be limited only by the scope of the following claims and not by the specific details presented in the description and explanation of the embodiments herein.
[0043] List of reference symbols:
[0044] 20 Water sound receiving arrangement
[0045] 22 waterborne sound receivers
[0046] 24 water silencers
[0047] 26 Soundproofing layer
[0048] 28 cavity
[0049] 30 carrier layer
[0050] 32 sound wave breaking element
[0051] 34 spring element
[0052] 36 sound reflector
[0053] 38 Opening
[0054] 40 rooms
[0055] 42 underwater vehicle
[0056] 44 first shell
[0057] 46 second shell
[0058] 48 pressure hulls
[0059] 50 space
[0060] 52 flat shell elements
Claims
Claims: Underwater sound receiving arrangement (20) comprising: an underwater sound receiver (22) configured to convert incident underwater sound into an electrical signal corresponding to the sound pressure; an underwater sound absorber (24) comprising a sound-absorbing layer (26) comprising a sound-soft material to reflect incident underwater sound in a damped manner; wherein the underwater sound absorber (24) has a curvature to create a cavity (28) between the underwater sound receiver (22) and the underwater sound absorber (24). Underwater sound receiving arrangement (20) according to claim 1, wherein the underwater sound absorber (24) has a sound wave refraction element (32) extending from the curvature into the cavity (28). Water sound receiving arrangement (20) according to one of the preceding claims, wherein the sound attenuation layer (26) lines the water sound silencer (24) such that the sound attenuation layer (26) limits the cavity (28).Water sound receiving arrangement (20) according to one of the preceding claims, wherein the water sound silencer (24) has a substantially sound-transparent carrier layer (30) on a side facing away from the cavity (28), on which the sound attenuation layer (26) is arranged.
5. Underwater sound receiver arrangement (20) according to one of the preceding claims, wherein the underwater sound silencer (24) either has the absence of a mechanical connection between the underwater sound receiver (22) and the underwater sound silencer (24) or wherein a mechanical connection between the underwater sound silencer (24) and the underwater sound receiver (22) has acoustic decoupling.
6. Underwater sound receiver arrangement (20) according to one of the preceding claims, wherein the underwater sound receiver (22) is an underwater sound receiver of a plurality of underwater sound receivers, wherein the underwater sound receivers (22) of the plurality of underwater sound receivers are arranged linearly or planarly, wherein the cavity (28) of the underwater sound silencer is arranged behind the underwater sound receivers of the plurality of underwater sound receivers.
7. Underwater sound receiver arrangement (20) according to one of the preceding claims, wherein the cavity (28) extending from the underwater sound receiver (22) has a maximum depth that corresponds to at least half the wavelength of a lower cutoff frequency of the underwater sound receiver arrangement.
8. Water sound receiving arrangement (20) according to one of the preceding claims, wherein the water sound receiving arrangement has the absence of a water sound reflector (36).
9. Underwater sound receiver arrangement (20) according to one of claims 1 to 7, wherein an underwater sound reflector (36) is arranged adjacent to the underwater sound receiver (22), which is configured to amplify the sound waves incident on the underwater sound transducer (22).
10. Underwater sound receiving arrangement (20) according to claim 9, wherein the underwater sound reflector is mechanically connected to the underwater sound silencer (24), the mechanical connection comprising a shock mounting of the underwater sound reflector.
11. Water sound receiving arrangement (20) according to claim 10, wherein the water sound reflector is connected to the water sound damper (24) by means of a moment joint to enable shock mounting of the water sound reflector (36).
12. Water sound receiving arrangement (20) according to claim 10 or 11, wherein the water sound silencer (24) forms a spring element (34) with which the water sound reflector (36) is mechanically connected, wherein the spring element enables the shock mounting of the water sound reflector.
13. Underwater sound receiver arrangement (20) according to one of claims 2 to 12, wherein the underwater sound receiver (22) has a linear extension or an extension in a plane, wherein the underwater sound receiver (22) has an inclination relative to the sound wave refraction element (32).
14. Underwater vehicle (42) with the following features: a sonar receiver arrangement (20) according to one of the preceding claims, a first shell (44) that bounds a pressure hull (48), and a second shell (46) that encloses the first shell (44), wherein the second shell (46) is spaced apart from the first shell (44) such that a space (50) is formed between the first and the second shell; wherein the sonar receiver arrangement (20) is arranged in the space (50) between the first shell and the second shell. A submersible vehicle (42) with the following features: wherein the second shell comprises a plurality of interconnected planar shell elements (52a, 52b, 52c) such that the sonar cross-sectional area of the submersible vehicle (42) is minimized; wherein the sonar receiver (22) or sonar receiver (22) of the plurality of sonar receivers (22) is arranged parallel to a planar shell element of the plurality of planar shell elements.