DE102006051921B3 - Acoustic underwater antenna for e.g. surface ship, has electronic module designed as molded part that is supported at shell, where module is axially and immovably fixed at cables, which are diametrically arranged parallel to module axis - Google Patents

Abstract

The antenna has electronic components for processing electric transducer signals, where the components are attached to electro-acoustic transducers (29). Two of the components and the associated adjacent transducers are combined in an electronic module (28), which is designed as a molded part supported at a shell. Each of the two adjacent transducers is carried at two free sides of the module, where the sides are turned away from each other, and the module is axially and immovably fixed at two load cables (26, 27), which are diametrically arranged parallel to an axis of the module.

Description

The The invention relates to an acoustic underwater antenna in the preamble of claim 1 defined genus.

A well-known underwater antenna known as marine seismic streamers, which forms the acoustic part of a towed antenna ( DE 42 08 178 A1 ), has a skeleton with two traction cables and in the longitudinal direction of the traction ropes spaced from each other arranged shaped pieces which are fixed axially immovably on the diametrically extending on the fittings two traction cables. The skeleton is retracted into an antenna sleeve formed as an elastic tube, wherein each fitting is supported with its fitting shell over two axially spaced annular strips of open-cell PU foam on the inner wall of the antenna shell or the hose. In a central through-hole of each fitting, a single-hydrophone-implemented electroacoustic transducer is used, which is enclosed by a sleeve of open-cell foam. Each transducer is connected to a tube inside through the fittings passed, electrical line. The electrical leads lead to electronic assemblies for the signal processing of the electrical converter output signals. At the output of each electronic module, also called channel, is the interference-free, amplified, digitized output signal. The hose is closed at the end and filled with a liquid. The fittings are used to form the dimensional stability of the hose, the axially immovable mounting of the transducer in the hose and for damping the liquid flow in the hose and thus to reduce noise to the transducer.

In the case of trailing antennas, it has recently been adopted to package the electronic assemblies in flameproof housings and to arrange them together with the transducers in the underwater antenna, ie in the acoustic part of the towed antenna. In this case, each electronic module defining a channel is spatially assigned to a transducer, so that in the longitudinal direction of the underwater antenna always alternately a transducer and an electronics housing follow each other. Such a towed antenna is for example by the DE 198 11 335 C1 known. Here are in an antenna shell filling gel body hydrophones and electronic components alternately lined up. In this construction, a sufficient longitudinal distance between adjacent transducers is required in the one hand housed the electronics housing and on the other hand clearance for the strain relief of electrical cables and cables must be created and therefore can not be made arbitrarily small. Since the longitudinal distance between the transducers is adapted to the receiving or transmitting frequencies of the underwater antenna of the acoustic part for the formation of directional characteristics, the receiving or transmitting frequency of the underwater antenna is set an upper limit, if transmission or reception over a single main lobe of the directional characteristic is to be ensured.

A known converter module ( DE 196 12 503 A1 ) comprises two spaced apart transducers, a reflector and absorber material partition disposed between the transducers, and an electronic circuit in which the receive signals of the two transducers are amplified and digitized for transmission. Transducer elements, partition and electronic circuit are arranged in a polyurethane mold-filled cylindrical shape. The partition has T-profile and separates transducer elements and electronics circuit from each other in such a way that the two transducer elements are placed on the left and right of the middle web of the partition and the electronic circuit above the transverse web of the partition. By the partition acoustic shading of the two transducer elements is achieved, so that each transducer element receives only sound waves from a half-space in front of the partition wall.

Of the Invention is based on the object, the structural design of a Underwater antenna design so that within the antenna shell of the Space requirement between in the longitudinal direction the antenna shell successive, electro-acoustic transducers kept small can be.

The Task is inventively by the features in claim 1 solved.

The underwater antenna according to the invention has the advantage that by the combination of two electronic modules belonging to adjacent transducers to an electronic module after every other converter in the converter chain an empty space is present, which increases the flexibility of the underwater antenna, for example when their tumbling, and which can be used for a strain relief of electrical cables and cables, for example by their crosses. The distance between the two transducers of an electronic module associated transducer pair can be fully used for the accommodation of the electronic module and minimized by appropriate structural design of the electronic module. A minimized distance between the transducers, in turn, has the advantage that the operating frequency (transmitting and / or receiving frequency) of the underwater antenna can be shifted to higher frequencies and directional characteristics for unambiguous transmission in or reception from only one main direction for operating frequencies well above 10kHz rea can be eliminated and grating praise is avoided. The formation of the electronic modules as on the antenna shell-supporting moldings and their axially immovable fixation on the traction ropes not only saves the otherwise used, cost-increasing, sound-transparent mounts for the converter, but also creates space in the longitudinal direction of the antenna shell by eliminating them. At the same time a stiffening of the antenna shell is achieved.

Expedient embodiments the underwater antenna according to the invention with advantageous developments and refinements of the invention result from the other claims.

According to one advantageous embodiment of the Invention is the support the electronic modules on the antenna shell advantageously over revolving Strip, preferably over two circumferentially spaced strips of plastic. By This plastic strip will provide an acoustic decoupling of antenna shell and Electronic modules, in particular the content Erten converter achieved. If the plastic strips are made of open-pore PU foam, so can the electronic modules - like the well-known fittings described above - at the same time for damping the Liquid flow in the usual closed at the end and filled with a liquid antenna shell and thus for noise reduction be used on the transducers.

According to one advantageous embodiment of the Invention, each electronic module has at least two with electronic components stocked Printed circuit boards, which are aligned transversely to the module axis and on the outside facing plate surfaces each carrying a transducer. This production engineering structure of the electronic module allows a very small axial length and thus a possible very small distance between the transducers to realize a high-frequency underwater antenna. The SMD-technology printed circuit board assembly with direct support of the electronic components on the transverse to the longitudinal axis the underwater antenna aligned populated circuit boards does not allow only a further reduction of the axial length of the electronic module, but also brings sufficient pressure resistance of the electronic module for the Use of the underwater antenna in greater depth with it.

The electrical connections between the electronic assemblies the stocked PCBs are for a space-saving installation in the module housing formed flexible. Advantageous becomes a so-called Star-Flex circuit board used, which consists of at least two rigid printed circuit boards for assembly and a mechanically fixed flexurally soft interconnect in the form of a permanent one flexible cable.

According to one advantageous embodiment of the Invention have the stocked Circuit boards edge over the plate circumference arranged distributed, groove-like cutouts for execution of traction cables and electrical cables and cables. The assembled printed circuit boards be marginally in mutually axially spaced grooves of a composed of two housing halves, front side open module housing held. Through this constructive design of the electronic modules results in a on the inner wall of the antenna shell abstützendes Skeleton of traction cables and electronic modules with converter pairs, wherein the individual electronic modules with converter pairs in one for the assembly and repair the towed antenna advantageous way in the skeleton can be inserted or removed from the skeleton, without that the rest Electronic modules or the entire skeleton must be dismantled. Furthermore is a twisting of underwater underwater antenna by the arrangement of the traction cables inhibited.

According to one advantageous embodiment of the Invention are the transducers of each transducer pair of Elelektronikmodule in the module axis. The directional characteristic formed by the transducer signals has all around a horizontally small opening angle. With a However, target positions located in such an underwater antenna are ambiguous, since can not be distinguished, whether the located goal tax or port side of the longitudinal axis the antenna shell lies.

According to an alternative embodiment of the invention, all transducers are arranged to the module axes with radial spacing on the printed circuit board. The successive in the longitudinal direction of the antenna shell transducer are offset from each other by a circumferential angle, which is arbitrary and is set stochastically. Now, if the transducer signals are processed in such a manner as described in US Pat DE 44 45 549 C1 is described, a directional characteristic of the underwater antenna is obtained, which points only to one side of the towed antenna.

According to an advantageous embodiment of the invention, each electro-acoustic transducer consists of three transducer elements with omnidirectional directivity, which are arranged offset in the same radial distance to the module axis and against each other by the same circumferential angle outside in the module housing. Preferably, each transducer element is a hydrophone. Depending on the current position of the hydrophones, which can be detected for example with a position sensor, output signals from each two of the three transducer elements after Passing through suitable time delay elements to the output of the electro-acoustic transducer summarized, which corresponds to a cardioidförmigen Eigenrichtcharakteristik the transducer. With these output signals of all electroacoustic transducers directional characteristics are formed, the main receiving directions each have to one side of the towed antenna and thus provide unique DF results. The signal technical summary of the output signals of the three transducer elements of an electroacoustic transducer is exemplified in the DE 31 51 028 A1 , there 9 , described.

The The invention is based on embodiments shown in the drawing closer in the following described. Show it:

1 a side view of a towed by a surface vessel towed antenna,

2 a side view of a designed vertical antenna,

3 a section of a longitudinal section of an acoustic section of an acoustic part in the towed antenna according to 1 or in the vertical antenna according to 2 .

4 an enlarged view of the section IV in 3 with longitudinally cut electronic modules,

5 a plan view of laid in the sheet level assembled printed circuit boards of an electronic module in 4 .

6 a view in the direction of arrow VI in 5 the assembled printed circuit boards placed in the installed position,

7 a same representation as in 5 according to a further embodiment.

In the 1 in a towed antenna 10 and in 2 in a vertical antenna 11 integrated underwater antenna provides each an elongated, tubular acoustic part 12 the antennas 10 . 11 , which is equipped with electro-acoustic transducers. In both embodiments, the acoustic part 12 designed as a receiving antenna for receiving sound waves propagating in the water. Of course, the acoustic part 12 also be used to send out sound. The acoustic part 12 is made up of several acoustic sections 121 assembled via couplings 13 are releasably connected together.

At the in 1 schematized towed antenna 10 according to 1 is the acoustic part 12 via a damping module 14 on a tow cable 15 attached, that at his from the damping module 14 Abandoned end on an aboard a watercraft 16 located, drivable drum 17 is fixed. At the other end of the acoustic part 12 is another damping module 18 attached to the one of the acoustic part 12 turned away end of a towing brake 19 attacks. By means of the drum 17 becomes the towed antenna 10 discharged into the water and caught up again. The watercraft 16 may be a surface ship or an underwater vehicle, eg submarine.

At the in 2 schematically illustrated vertical antenna 11 is the acoustic part 12 with its over clutches 13 juxtaposed acoustic sections 121 in turn, at the end of damping modules 14 respectively. 18 attached. The damping module 14 is with a buoyant body 20 and the damping module 18 with a stabilizing member 21 with stabilizing fins 22 and ballast weight 23 connected. The acoustic part 12 is over an electrical cable 24 or an optical fiber with an anchored watercraft 16 integrated central unit or via radio with an evaluation unit.

In 3 is a section of an acoustic section 121 of the acoustic part 12 partially shown in longitudinal section. All acoustic sections 121 of the acoustic part 12 are identical. The acoustic section 121 has an antenna shell in the form of an elastic, tensile hose 25 , eg made of polyurethane with inserted carbon fibers or Kevlar fibers on. In the hose 25 is a skeleton with two carrying or traction ropes 26 . 27 and on the ropes 26 . 27 axially immovably mounted electronic modules 28 moved in. The electronic modules 28 are as fittings for shape stabilization of the hose 25 trained and serve to accommodate the converter 29 ( 4 ) and electronic assemblies for the signal processing of the electrical output signals of the converter 29 , It is every converter 29 associated with an electronic module, which essentially contains operational amplifier, filter, sample and hold circuit and A / D converter or sigma-delta A / D converter. At the output of each electronic module, also called channel, the noise-free, amplified and digitized output signal is available. The channels are on electrical lines 31 connected by the towed antenna 10 or the vertical antenna 11 through to a arranged in the vessel electronic control center or a radio transmission link. The hose 25 is at the clutches 13 closed and filled with an electrically insulating substance, such as gel or oil. Every converter 29 is realized by a single hydrophone.

In 4 is one of the electronic modules 28 detailed in longitudinal section. Every electronics module 28 has a module housing consisting of two housing halves 32 with a circular cross-section, which is open at the front. The two housing halves are made of two semicircular housing shells 321 . 322 formed, which lie on one another with their shell edges and the cylindrical module housing 32 result. The module housing 32 is supported by two plastic strips 33 spaced axially from each other around the module housing 32 run around, on the inner wall of the hose 25 and thus ensures its dimensional stability. The plastic strips 33 are in two mutually axially spaced annular grooves 43 in the outer jacket of the module housing 32 inserted and are radially over the module housing 32 before, so that between module housing 32 and hose 25 an annular gap remains. The plastic strips 33 are made of open-pore or open-cell PU foam and act as attenuators for acoustic decoupling between hose 25 and module housing 32 ,

In the module housing 32 are two transducers 29 recorded on the remote module sides of the electronics module 28 are held at this distance. Every converter 29 An electronic module is assigned to the output signal of the converter 29 or the channel for the converter 29 supplies, so the electronics module 28 has two channels. Each electronic module consists of one or more populated printed circuit boards 35 , The assembled printed circuit boards 35 are axially spaced from each other in transverse orientation to the module axis - and thus to the axis of the acoustic section 121 - arranged and in the module housing 32 established. For this purpose, the assembled printed circuit boards 35 at the edge in ring grooves 36 one, the distance from each other in the inner wall of the two housing shells 321 . 322 are incorporated and in the module housing 32 rotate 360 °. The two in the electronics module 28 outside populated printed circuit boards 35 each carry one of the transducers 29 ,

In the described embodiment are in the module housing 32 a total of four printed circuit boards 35 intended. With two printed circuit boards 35 in each case one of the electronic assemblies is realized, which arranged on the outer side plates transducers 29 assigned. The assembled printed circuit boards 35 are electrically non-releasably electrically connected by integrated in a flexible band tracks. Single, on the assembled printed circuit boards 35 arranged components 38 of electronic assemblies in 4 indicated schematically. They are SMD components and lie directly on the printed circuit boards. The number of assembled printed circuit boards 35 of the electronic module 28 Of course, with their flexible interconnect connections can vary.

In 5 is a populated Star-Flex printed circuit board made of four printed circuit boards 35 with connections through flexible conductor strips 39 before installation in the module housing 32 shown in plan view. Of the four printed circuit boards equipped on both sides 35 are each in the installation position ( 4 and 6 ) facing away from each other surfaces of the two PCB pairs. On the two outer printed circuit boards 35 are the two converters 29 arranged. Every converter 29 is realized by a single hydrophone, which centrally on the respective populated printed circuit board 35 is placed so that all the hydrophones in the longitudinal axis of the hose 28 lie. The two-sided with components 38 equipped printed circuit boards 35 form the electronic assemblies. How out 5 it can be seen are the populated printed circuit boards 35 through the flexible strip conductors 39 connected with each other. When installing the resulting assembled printed circuit board chain in the module housing 32 become the populated printed circuit boards 35 moved directly to each other and the conductor strips 39 arched outward, as in 6 you can see. 6 makes a 90 ° to the representation in 4 rotated arrangement.

In the assembled printed circuit boards 35 There are several recesses at the edge 40 . 41 . 42 inserted so that they after installation of the assembled circuit boards 35 in the module housing 32 axially aligned with each other. The two diametrically arranged recesses are used 40 . 41 for carrying the traction cables 26 . 27 through the electronics module 28 and the remaining recesses 42 to carry out the electrical wiring 31 for connecting the channels of the electronic modules 28 ,

When installing the acoustic section 121 The skeleton is made in such a way that every electronic module 28 in the two pull ropes 26 . 27 mounted and each channel of the electronic module 28 to the electrical wires 31 is connected. For this purpose, the traction cables 26 . 27 in the recesses 40 . 41 and the electrical wires 31 in the recesses 42 the assembled printed circuit boards 35 of the electronic module 28 inserted. Thereafter, the module housing 32 by covering the two housing shells 321 . 322 closed, with the assembled printed circuit boards 35 with their edges in the grooves 36 in the housing shells 321 . 322 immerse in a positive fit. Then the module housing 32 with the two surrounding plastic strips 33 occupied, each in the annular grooves 43 on the top of the module housing 32 be inserted. All electronic modules 28 be about the module housing 32 on the ropes 26 . 27 set axially immovable, which is in 4 not shown. The axial distance of the electronic modules 28 is chosen such that the axial distance between the mutually facing transducers 29 two in the skeleton successive electronic modules 28 equal the transducer distance of the two in an electronic module 28 integrated converter 29 is. The white space 44 between two adjacent electronic modules 28 will strain relief the electrical wiring 31 used by these in the white space 44 be guided so that they are in the next electronic module 28 in spatially different recesses 42 in the assembled printed circuit boards 35 of the electronic module 28 einliegen. In the embodiment of 4 is exemplified here that the lines to be seen 31 in successive electronic modules 28 in diametrically opposed recesses 42 the assembled printed circuit boards 35 run.

As the number of for the realization of the electronic module 34 used assembled printed circuit boards 35 and their axial distance from each other and otherwise the size of the module housing 32 can be varied, the distance of an electronic module 28 associated two transducers 29 corresponding to a desired transmission or reception frequency of the acoustic section 121 be chosen and also be made so small that the reception frequency of the acoustic section 121 can be moved to a higher frequency range. The distance between two electronic modules 28 each other then has to turn according to the distance between the two in an electronic module 28 integrated transducers 29 be chosen so that all transducers 29 in the acoustic section 121 have the same axial distance from each other.

In an alternative embodiment of the acoustic section 121 are the transducers 29 not as in the embodiment according to 3 and 4 in the longitudinal axis of the hose 25 but at a radial distance from the longitudinal axis on the two outer printed circuit boards 35 the individual electronic modules 28 arranged. Every converter 29 is also realized here by a single hydrophone. All transducers 29 within the acoustics section 121 are offset from one another by circumferential angles, the offset angles being different and the order of displacement being chaotic. With such an acoustic section 121 when a bearing is targeted, there is a clear distinction between a port or starboard attitude of the target. The signal processing at such a transducer placement along the tube 25 is for example in the DE 44 45 549 C1 described.

In the 7 in the pre-installed state in plan view, modified Star-Flex printed circuit board of the electronic module 28 is different from the one in 5 illustrated Star-Flex circuit board only in that each on the two outer printed circuit boards 35 arranged electroacoustic transducer 45 three omnidirectional transducer elements 451 . 452 and 453 which are placed in the circuit board plane in the vertices of an equilateral triangle. Each electroacoustic transducer element 451 . 452 . 453 is realized by means of a hydrophone. On the separate interconnected circuit boards, the components of the electronic assembly are arranged, each one of the two electro-acoustic transducers 45 assigned. Also, in the electronics module 28 still a position sensor (not shown) integrated. In each of a converter 45 associated electronic assemblies are the output signals of two pairs of transducer elements of the transducer elements 451 . 452 and 453 as output signals of the converter 45 issued, as in the embodiment in 3 to 6 via the output as digitized signals on the electrical wires 31 are given. The respective pairing of the transducer elements 451 . 452 . 453 is determined by the output signal of the position sensor. Each electronic module thus has two outputs or channels and each electronic module 28 is thus constructed four-channel and via the four channels to the lines 31 connected. The two paired transducer elements each yield a transducer 45 with a cardiode directional characteristic having a zero to one side of the connecting line of the transducer elements of the transducer pair, wherein the zero point is one pairing of two of the three transducer elements to one side and the other pairing of two of the three transducer elements to the other side the connecting line points. With such a design of the electroacoustic transducer 45 on the two facing away from each other end sides of the electronic module 28 can be clearly distinguished when sighting targets between port and starboard bearing. An exemplary embodiment for the signal processing of the output signals of the transducer element pairs is shown in FIG DE 31 51 028 A1 ( 9 ).

at an alternative training of the acoustic section would be possible, the not to integrate two converters in the electronics module, but to be arranged separately on both sides of the electronic module. Also then it would be by combining the channels of two adjacent electroacoustic transducers in the electronic module, the advantage of the converter distance small construction and the associated high receive and / or transmit frequency the underwater antenna feasible.

Claims (13)

Acoustic underwater antenna with fixedly spaced, electroacoustic transducers ( 29 ), the converters ( 29 ) associated with electronic assemblies for the signal processing of the electrical transducer signals and with a transducer ( 29 ) and electronics assemblies surrounding antenna shell, characterized in that in each case two electronic assemblies, the neigh barten converters ( 29 ) in an electronic module ( 28 ) are formed, which is designed as a support piece on the antenna shell and on each of its two mutually remote free module sides one of the two adjacent transducer ( 29 ) and that the electronic modules ( 28 ) on traction cables running parallel to the module axis, preferably on two traction ropes diametrically arranged relative to the module axis (US Pat. 26 . 27 ), fixed axially immovable. Underwater antenna according to claim 1, characterized in that the electronic module ( 28 ) at least two with electronic components ( 38 ) equipped printed circuit boards ( 35 ), which are aligned transversely to the module axis and on outwardly facing plate surface in each case one of the two transducers ( 29 ) wear. Underwater antenna according to claim 2, characterized in that of printed circuit board ( 35 ) to PCB ( 25 ) contains a flexible strip containing conductor tracks ( 39 ) leads. Underwater antenna according to claim 2 or 3, characterized in that the printed circuit boards ( 35 ) at the edge over the circumference distributed, groove-like recesses ( 40 . 41 . 42 ) for carrying the traction cables ( 26 . 27 ) and electrical cables ( 31 ) exhibit. Underwater antenna according to one of claims 2 to 4, characterized in that the electronic module ( 28 ) a module housing realizing the fitting ( 32 ), which is composed of two housing halves and frontally open, and that the circuit boards ( 35 ) at the edges in mutually axially spaced grooves ( 36 ) of the module housing ( 32 ) are held positively. Underwater antenna according to claim 5, characterized in that the antenna envelope has a circular cross-section, the printed circuit boards ( 35 ) are circular and the housing halves of the module housing ( 32 ) Semicircular housing shells ( 321 . 322 ) are. Underwater antenna according to claim 5 or 6, characterized in that the support of each electronic module ( 28 ) on the antenna cover over plastic strips ( 33 ) in two in the module housing ( 32 ) spaced, outer circumferential annular grooves ( 43 ) are inserted and over the outside of the module housing ( 32 ) protrude radially. Underwater antenna according to one of claims 1 to 7, characterized in that the electroacoustic transducers ( 29 ) lie in the module axis. Underwater antenna according to one of claims 1 to 7, characterized in that the electroacoustic transducers ( 29 ) are arranged at a radial distance to the module axis and offset from each other by a circumferential angle, and that in the antenna envelope successive electronic modules ( 28 ) are rotated against each other so that all electroacoustic transducers ( 29 ) are offset from one another by circumferential angle offset. Underwater antenna according to one of claims 1 to 7, characterized in that each electroacoustic transducer ( 45 ) three omnidirectional transducer elements ( 451 . 452 . 453 ), which are arranged offset in the same radial distance to the module axis and against each other by a same circumferential angle. Underwater antenna according to one of claims 1 to 10, characterized in that the antenna casing is a flexible hose ( 25 ). Underwater antenna according to claim 11, characterized in that it comprises at least one acoustic section ( 121 ) towed in the water towed antenna ( 10 ). Underwater antenna according to one of claims 1 to 12, characterized in that it comprises at least one acoustic section ( 121 ) a vertical antenna ( 11 ) which is disposed in the water in a vertical orientation.