EP2951610A1

EP2951610A1 - Underwater sound signal, underwater transmitter or underwater receiver, underwater sonar, underwater vehicle and retrofitting kit

Info

Publication number: EP2951610A1
Application number: EP14703520.8A
Authority: EP
Inventors: Nils Theuerkauf
Original assignee: Atlas Elektronik GmbH
Current assignee: Atlas Elektronik GmbH
Priority date: 2013-01-29
Filing date: 2014-01-03
Publication date: 2015-12-09
Also published as: DE102013100894A1; WO2014117767A1

Abstract

In particular in the case of a side-scan sonar, large intensities with respect to the sound pressure under water are emitted in order to be able to detect objects at large distances, with the result that the reflected signal of very distant objects can be detected well. This procedure has some disadvantages. In order to be able to achieve the high sound pressure, high-performance energy sources such as batteries are necessary. In addition, (interference) signals are also reflected at the surface of the water. Furthermore, reflections of objects in the vicinity are very strong, with the result that the sensitivity of underwater microphones has to be reduced. The invention therefore relates to an underwater sound signal which has a first transit time difference and/or a first intensity difference along a first irradiation angle, wherein the first transit time difference and/or the first intensity difference are/is impressed on the underwater sound signal and this impressing process occurs, in particular, during transmission or reception.

Description

Underwater sound signal, underwater transmitter or

Underwater receiver, underwater sonar, underwater vehicle and retrofit kit

The invention relates to an underwater sound signal which has a first time difference and / or a first intensity difference along a first radiation angle and an underwater transmitter or receiver, and an underwater sonar

Underwater vehicle, a watercraft and a retrofit kit.

[02] Especially with a side scan sonar, um

[03] To be able to detect objects at great distances, emitted large intensities with respect to the sound pressure under water in a wide sector, so that the reflected signal is well detectable both from nearby and distant objects.

[04] This procedure has some disadvantages. In order to achieve the high sound pressure in a large sector, powerful energy sources such as batteries are necessary. In addition, (interfering) signals are also reflected on the water surface (multipath propagation).

Furthermore, the echoes of nahliegender objects are very strong compared to objects in long distances, resulting in high demands on the dynamics of the receiver. [05] The object of the invention is to improve the disadvantages of the prior art.

[06] The task is solved by a

Underwater sound signal, which is a first

Delay difference and / or a first

Having intensity difference along a first emission angle, wherein the first time difference and / or the first intensity difference is impressed on the underwater sound signal and these impositions takes place in particular when sending or receiving.

[07] By sending such

Underwater sound signals, the transmitter can be made in smaller designs, as cooling and

Energy supply can be dimensioned smaller or designed. In addition, a lower cooling capacity is necessary. Also under the same energy supply underwater sound signals can be sent over a longer period of time than in the prior art. In particular, the transmission power can be reduced by up to 80%.

On the receiver side, the receivers can be used with high sensitivity in order to be able to detect objects that are far away, while at the same time highly-sensitive reflected signals from the near range can be measured.

[09] In addition, there is less volume reverberation as well as surface reverberation. Also multipath effects, which arise in particular by the additional reflection on the water surface, can be minimized. [10] The following terminology is explained:

[11] "Underwater sound signals", hereinafter also

Underwater signals called include all

Sound signals used to locate objects underwater. In particular, the

Underwater sound signals includes, which are used in a sonar (sound navigation and ranging). Underwater ultrasound signals in the range from 10 kHz to 1000 kHz are particularly preferred. Present underwater sound signals are generated in particular by means of piezoceramics under water.

[12] A "runtime difference" includes both a delayed and a premature emission with respect to an unaffected underwater sound signal.

[13] An "intensity difference" is given when the intensity deviates from the intensity of a reference signal, wherein the reference signal has a substantially uniform and over a (transmission) angle φ constant intensity.

Both the intensity difference and the delay difference can be selected via the aperture of the antenna angle-dependent so that they are adapted to the task. In particular, you can

Intensity difference and time difference are adapted to the angle-dependent seabed removal. The aperture of the antenna designates the free, active opening through which the sound waves are sent or received.

[16] An "angle of radiation" can be described in particular by a mathematical line angle, which in turn can be described by a mathematical angular measure Alternatively, the line angle can be called a one-dimensional angle Degrees between 0 ° and 360 ° and assume a value between Ogon and 400gon in the geodesic angle measure.The emission angle extends in particular along the aperture.

[17] "Imprinting" involves a technical influence on the underwater sound signal, which results in a corresponding difference in transit time and / or an intensity difference compared to an uninfluenced signal, which can occur during the actual transmission as well as at the reception This can be done, in particular, by passing an already emitted signal first through water, then passing it through diffraction to layers of different thicknesses or different acoustic impedance before it reaches the actual signal Receiver reached.

[18] In another embodiment, the underwater scarf signal has a second transit time difference and / or a second intensity difference along a second emission angle, wherein the first emission angle and the second emission angle are not parallel to one another such that the first emission angle and the second emission angle form a solid angle, the second transit time difference and / or the second

Intensitätsunterschied the underwater sound signal is impressed and this imprinting is done especially when sending or receiving.

[19] Thus, an underwater sound signal can be provided which is suitable to scan areal areas.

[20] By the "non-parallelism" or the

"Orthogonality" of the first and second emission angles includes, for example, an emitted cone of sound .Furthermore, non-parallelism comprises both perpendicular line angles and other angles.

[21] The "solid angle" describes in particular the size of a spatial area, which is spanned by a conical shell.

[22] In order to be able to provide different underwater sound signals with different propagation characteristics for sonars, one of the emission angles can have a value between 0 ° and 360 °, in particular between 0 ° and 180 ° or between 0 ° and 90 ° or between 10 ° and 80 ° , Even smaller angles, for example, between 20 ° and 40 ° can be realized. [23] The angle value of 0 ° to 360 ° can be achieved, for example, by a signal emitted by a piezoceramic ball or a piezoceramic ring. Even with small distances from each other spaced transmission elements can fill such radiation angle, it is harmless that small areas are recessed. Small distances in this context include values from 1 mm to values of a few centimeters, depending in particular on the transmission wavelength. Roughly, the higher the transmission frequency the smaller the distance can be selected (eg 1000kHz corresponds to approx. 1mm distance).

[24] In a further embodiment, the imprinting of the running time difference and / or the intensity difference takes place by means of a damping element and / or by means of a transmitter and / or receiver geometry and / or by means of an electronic circuit.

[25] Thus, alternative generation methods for underwater sound signals according to the invention can be provided.

[26] The following terminology is explained:

[27] In particular, a "damping element" comprises a material which has a different velocity of propagation for sound than water, thus allowing both "decelerations" and "accelerations." In particular, the damping element in

Propagation direction of the water sound have different thicknesses, through which the underwater sound signal can be modeled technically. The imprinting by means of a "transmitter and / or receiver geometry" is effected, for example, by arranging several individual underwater sound transmitters not flat, but curved relative to one another Level differing structure are included.

[29] When imposing a running time difference or an intensity difference by means of a

"Electronic circuit" single transmitter or individual receiver are so controlled electronically that they premature or delayed sending or receiving to neighboring individual transmitters or receivers.

Furthermore, the object is achieved by an underwater transmitter or an underwater receiver, which emits or receives a previously described underwater sound signal.

[31] Thus, an underwater transmitter having a better range, lower volume reverberation, lower surface echo, lower multipath, lower transmission power, less cooling, lower power consumption, and a smaller size can be provided.

[32] Furthermore, the object can be achieved by an underwater transmitter or an underwater receiver, wherein the underwater transmitter or the underwater receiver is set up such that the underwater transmitter or the Underwater receiver an underwater sound signal actively and / or passively a first time difference and / or a first intensity difference along a first radiation angle and / or that the underwater transmitter or underwater receiver the underwater sound signal actively and / or passively imposes a second delay difference or a second intensity difference along a second radiation angle.

[33] This underwater transmitter or underwater receiver also has the advantages of the above-described underwater transmitter or underwater receiver.

[34] In one embodiment, the underwater transmitter has two or more subsenders and / or the underwater receiver has two or more sub-receivers.

This makes a particularly effective one

Underwater sound signal a time difference or an intensity difference can be impressed. It is particularly advantageous that any desired time differences and intensity differences can be realized. Thus, for example, the intensity and / or transit time can be impressed on the transmitter or receiver as a function of a distance of a seabed to be examined.

[36] In this case, the subsenders include both (piezo) ceramic filaments as well as planar (piezo) ceramic elements or arranged on a curved path (piezo) ceramic elements. In order to be able to emit underwater sound signals according to the invention, in particular with existing sonars, the active impingement can take place electronically. In particular, individual subscribers or sub-receivers can prematurely and / or late send or receive a sound signal.

[38] The big advantage in this case is in particular that an adaptation of the existing sonar to a system according to the invention can be easily implemented by a software update.

[39] In another embodiment, the passive imposition is effected by a geometric arrangement of the underwater transmitter and / or by a geometric arrangement of the underwater receiver and / or by a damping element.

[40] With regard to the realizations and definitions of the geometric arrangement and the damping element is made to previous versions, which apply analogously.

[41] In a further embodiment, the object is achieved by an underwater sonar, which has a previously described underwater transmitter and / or a previously described underwater receiver.

[42] Thus powerful locating devices for detecting underwater objects can be provided.

[43] Furthermore, the object is achieved by an underwater vehicle which has a previously described Underwater transmitter and / or a previously described underwater receiver and / or a previously described underwater sonar has.

The "underwater vehicle" includes both submarines (remotely controlled, autonomous, with and without crew) as well as buoys, torpedoes, or towing sonars.

[45] In a further embodiment of the invention, the object is achieved by a watercraft which has a previously described underwater transmitter and / or a previously described underwater receiver and / or a previously described underwater sonar and / or a previously described underwater vehicle.

[46] "Watercraft" as used herein includes all ships, platforms or other objects moving or lingering on the water.

Finally, the object can be achieved by a retrofit kit for retrofitting a sonar, wherein the retrofit kit emitted by a sonar or received underwater sound signal a first time difference and / or a first intensity difference along a first angle of radiation and / or that the underwater transmitter or underwater receiver the underwater sound signal a second transit time difference and / or a second intensity difference along a second

Imprints beam angle, this imprinting is done in particular when sending or receiving. [48] Thus, a component or a software update can be provided which sets in-use sonars such that these sonars send or receive a previously described underwater sound signal. This leads to high efficiency increases of existing sonar systems at low cost.

In a related form of expression of the retrofit kit is designed passive and / or active. Thus, alternative retrofit sets can be provided.

[50] For the definition of the terms "passive" and "active", reference is made to the previous remarks.

[51] In the following, the invention will be explained in more detail by means of exemplary embodiments. Show it

Figure 1 is a highly schematic representation of a

Underwater sounder with ceramic films,

FIG. 2 shows a highly schematic representation of a conventional, flat underwater sound transmitter,

FIG. 3 shows a highly schematic illustration of a curved underwater sound transmitter with several sub-underwater sounders,

Figure 4 is a schematic representation of a

Sidescan sonar with abscannable surface, Figure 5 is a graphical representation of a

Intensity curve as a function of distance and

Figure 6 is a schematic representation of an under

Water side scan sonar.

[52] In a first alternative of the

Underwater sounder 101, has a first

Underwater sounder 101 a variety of

Ceramic filaments 105, which are arranged on a carrier layer 103. The ceramic filaments 105 are made of piezoceramics, which are driven with a voltage perform a change in space, whereby a water column is impressed underwater sound signal.

[53] In a simple manufacturing method of the present underwater sounder 101, the ceramic filaments 105 are juxtaposed and filled by means of a resin. Subsequently, the ceramic block is cured and then enclosed with

Ceramic filaments 105 machined by means of a milling cutter. By the cutter, a defined surface, such as a curved surface, the ceramic block is impressed.

[54] The present first underwater sounder 101 is used differently. On the one hand, all ceramic filaments 105 are simultaneously subjected to voltage. Due to the different position of the Keramikfilamente 1 05 an underwater sound signal corresponding to the surface profile is emitted.

[55] Another alternative is to coat each individual ceramic filament individually. By corresponding earlier or later Beschälten a desired waveform with a corresponding desired signal intensity and or with an angle-dependent delay and / or intensity difference can be provided.

In a second alternative, a second underwater sounder 2 0 1 with flat, flat ceramic plates 2 05 configured. The ceramic plates 2 05 are spaced from each other (not shown).

[57] Because the ceramic plates 2 05 are connected from the inside (φ = 0) to the outside (cp = cp _max ), there is a transit time difference as a function of the angle cp, which emits a curved sound wave form 2 0 7. By a different timing of the wiring different underwater sound waveforms can be emitted. Alternatively or additionally, the individual ceramic plates 2 05 are connected such that different intensities are emitted in different directions.

In a third alternative, a third underwater sounder 3 0 1 curved - arranged on a support structure 3 03 - piezoceramic 3 05 on.

The geometric arrangement (curvature) is the simultaneous activation of the piezoceramics 3 05 the Underwater sound signal imprinted on a runtime difference. Alternatively or additionally, the individual piezoceramics 305 are connected in such a way that different intensities are emitted in different directions.

[60] As in the previous examples, a delay difference and / or an intensity difference can be impressed on a subsonic sound signal by time-delayed activation or by different activation.

[61] Each of the alternative underwater sounders 101, 201, 301 described above can be used in a sidescan sonar. In this side scan sonar 411, the bottom of the sea is scanned 415 on the left and 413 on the right.

[62] In order to minimize or avoid mutual interference, the scanned areas 413, 415 have a spacing 421, with the left area 415 having a width 418 and the right area 413 having a width 417. Overall, the seabed can be scanned over a total width of 423 and over a covered distance of 419.

[63] The fact that the sidescan sonar 411 moves under water, a whole "image" of the sea surface and any objects 641, 643 thereon can be determined.

[64] A sidescan sonar 611 with one of the previous underwater sounders 101, 201, 301 is below one Water surface 650 and arranged above the seabed. The distance 652 to the seabed is 10m, this can be less in shallow water and more in deep water.

[65] Basically, the wiring is as follows.

[66] The underwater sounder 101, 201, 301 is connected in such a way that the sound signal is emitted in the direction of the maximum range R _max 663 to be scanned with maximum intensity (cp = 0). As the angle φ increases, further signals are emitted, each with attenuating intensity, and finally the emission with the minimum intensity takes place with a minimum range R _m i _n 661 (cp = cp _max ) to be scanned.

By matching (depending on the height 652) of the underwater sound transmitters 101, 201, 301, the transmitted signals are modeled such that substantially similar intensities of intensity of the reflected sound signals are received at the side scan sonar 611.

As a result, in particular objects 641, 643, which are located at different distances from the sidescan sonar, can be detected similarly well.

[69] A typical intensity curve as a function of the direction of defection is shown in FIG. The area 531 corresponds to the surface and the area 533 is the course of the underwater signal. Reference sign list:

101 first underwater sounder

103 carrier layer

105 ceramic filament

201 second underwater sounder

203 carrier layer

205 level piezo elements

207 signal front

301 third underwater sounder

303 carrier layer

305 curved piezo element

411 Side Scan Sonar

413 right scanning area

415 left scan area

417 Scan width R

418 Scan width R

419 scan width

421 scan gap

423 Scan expansion

531 surface

533 Underwater signal

611 Side Scan Sonar

641 first item

643 second subject

650 water surface

652 vertical ground clearance

661 first sound control limit

662 second sound control limit

Claims

Claims:

1. Underwater sound signal 207, which has a first time difference and / or a first intensity difference along a first radiation angle (cp), characterized in that the first time difference and / or the first intensity difference is impressed on the underwater sound signal and this imprinting in particular at a transmission or a Received takes place.

2. Underwater sound signal according to claim 1, characterized in that the underwater sound signal has a second transit time difference and / or a second intensity difference along a second radiation angle, wherein the first angle and the second angle are not parallel to each other, so that the first line angle and the second line angle a Form solid angle, wherein the second time difference and / or the second intensity difference is impressed on the underwater sound signal and this imprinting takes place in particular during the transmission or reception.

3. Underwater sound signal according to one of the preceding claims, characterized in that one of the emission angle has an angle value between 0 ° and 360 °, in particular between 0 ° and 180 ° or between 0 ° and 90 ° or between 10 ° and 80 °.

4. Underwater sound signal according to one of the preceding claims, characterized in that the imprinting of the running time difference and / or the impressing of the intensity difference by means of a damping element and / or by means of a transmitter and / or receiving geometry and / or by means of an electronic circuit.

5. Underwater transmitter or receiver which emits or receives an underwater sound signal according to one of the preceding claims.

6. underwater transmitter or receiver, characterized in that the underwater transmitter or receiver is set up such that the underwater transmitter or receiver an underwater signal active and / or passive a first time difference and / or a first intensity difference along a first

Abstrahlwinkels and / or that the underwater transmitter or receiver the submarine signal active and / or passive imposes a second delay difference and / or a second intensity difference along a second radiation angle.

7. underwater transmitter (101,201, 301) or receiver according to claim 6, characterized in that the

Underwater transmitter two or more subsenders (105, 205,

305) and / or the underwater receiver has two or more sub-receivers.

8. underwater transmitter or receiver according to one of claims 6 or 7, characterized in that the active impingement is carried out electronically.

9. Underwater transmitter or receiver according to one of claims 6 to 8, characterized in that the passive impingement is effected by a geometric arrangement of the underwater transmitter and / or by a geometric arrangement of the underwater receiver and / or by a damping element.

10. Underwater sonar comprising an underwater transmitter and / or an underwater receiver according to one of claims 5 to 9.

An underwater vehicle (441, 611) comprising an underwater transmitter and / or an underwater receiver according to any one of claims 5 to 9 and / or underwater sonar according to claim 10.

A watercraft comprising an underwater transmitter and / or an underwater receiver according to any one of claims 5 to 9 and / or underwater sonar according to claim 10 and / or an underwater vehicle according to claim 11.

13. Retrofit kit for retrofitting a sonar, wherein the retrofit kit a sonar sent or received underwater sound signal a first time difference and / or a first intensity difference along a first radiation angle and / or that the underwater transmitter or receiver the underwater signal a second time difference and / or a second Imprinted difference in intensity along a second emission angle, said imprinting takes place in particular during a transmission or a reception.

Retrofit kit according to claim 13, characterized in that the retrofit kit is designed passive and / or active.