EP0263314B1 - Disposition de transducteurs - Google Patents

Disposition de transducteurs Download PDF

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Publication number
EP0263314B1
EP0263314B1 EP87113165A EP87113165A EP0263314B1 EP 0263314 B1 EP0263314 B1 EP 0263314B1 EP 87113165 A EP87113165 A EP 87113165A EP 87113165 A EP87113165 A EP 87113165A EP 0263314 B1 EP0263314 B1 EP 0263314B1
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EP
European Patent Office
Prior art keywords
transducer
transducers
frequency band
frequency
group
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP87113165A
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German (de)
English (en)
Other versions
EP0263314A2 (fr
EP0263314A3 (en
Inventor
Manfred Meyersieck
Manfred Siegel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fried Krupp AG
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Fried Krupp AG
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Publication date
Application filed by Fried Krupp AG filed Critical Fried Krupp AG
Publication of EP0263314A2 publication Critical patent/EP0263314A2/fr
Publication of EP0263314A3 publication Critical patent/EP0263314A3/de
Application granted granted Critical
Publication of EP0263314B1 publication Critical patent/EP0263314B1/fr
Anticipated expiration legal-status Critical
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Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/26—Sound-focusing or directing, e.g. scanning
    • G10K11/34—Sound-focusing or directing, e.g. scanning using electrical steering of transducer arrays, e.g. beam steering
    • G10K11/341—Circuits therefor
    • G10K11/343—Circuits therefor using frequency variation or different frequencies

Definitions

  • the invention relates to a transducer arrangement for the directed transmission and / or reception of sound waves of the type mentioned in the preamble of claim 1.
  • Sonar systems are used for reconnaissance or location tasks at sea or for presentations of combat situations or for coastal protection, with their transducer arrangements receiving waterborne sound over a wide frequency range.
  • Bearings to targets are obtained via directional characteristics, which are formed with the received signals of the transducer arrangement.
  • Target distances are determined in that directional sound is sent and received after reflection at the target, the transit time between sending and receiving indicating the distance to the target.
  • the directional characteristic has at least a constant opening angle in a wide frequency range.
  • a transducer arrangement is known in which the individual has an opening angle of the directional characteristic that is constant over the frequency range under consideration
  • Transducers of the transducer arrangement are connected downstream of low-pass filters whose cutoff frequencies rise towards the center of the transducer arrangement, so that the transducer arrangement is effective over the entire length at low frequencies and its effective length is shortened towards higher frequencies. It is thereby achieved that the ratio of the effective length of the transducer arrangement and the wavelength of the sound received, which determines the opening angle, is the same for all frequencies.
  • a directional characteristic pointing to the normal of the transducer arrangement, which is formed by summation of the received signals, has a constant opening angle over the entire frequency range.
  • the low-pass filters In order to be able to form a direction for pivoting the directional characteristics with the filtered signals, the low-pass filters must have the same phase and amplitude responses in spite of different cut-off frequencies. A corresponding filter implementation is extremely difficult. Another problem is that secondary lobes of such a transducer arrangement are also frequency-dependent, since the transducers are arranged equidistantly over the length of the transducer arrangement and the effective number of transducers decreases with increasing frequency.
  • the object is achieved according to the invention in a converter arrangement of the type specified in the preamble of claim 1 by the features in the characterizing part of claim 1.
  • the same number of converters are combined to form a converter group for each frequency band and the converter groups are arranged nested one inside the other along the length of the converter arrangement.
  • the distances between adjacent transducers are not the same if neighboring transducers belong to different transducer groups.
  • the distance between transducers of the same transducer group is, however, of the same size and is selected depending on a minimum wavelength in the associated frequency band in accordance with the uppermost frequency of this frequency band.
  • the distances are greatest and, for example, half as large as the smallest wavelength resulting from the upper limit frequency of this frequency band.
  • the transducers in this transducer group are distributed equidistantly over the entire length of the transducer arrangement.
  • the transmit or receive signals of the transducers of this transducer group are processed to form the directional characteristic.
  • the same number of transducers is equidistant at a distance of half the wavelength corresponding to the highest frequency in this frequency band between the existing transducers, with a shorter one rather than the entire length of the transducer arrangement between the outermost transducers belonging to this transducer group Distance is. This shorter distance is equal to the number of transducers in the transducer group multiplied by their distance from one another.
  • the ratio between the minimum wavelength in this frequency band or the distance between the transducers of this transducer group and the distance of the most distant transducers is again the same as the ratio between the smallest wavelength in the lowest frequency band or the spacing of the transducers of the first-mentioned transducer group divided by the entire length of the transducer assembly.
  • the advantage of this dimensioning is that the dimensioning rule known for achieving a constant opening angle for the two frequency bands, namely a constant ratio of wavelength and effective antenna length, is guaranteed and, in addition, the same antenna assignment is achieved through the number and spacing of the transducers per transducer group is such that the opening angle and secondary lobe behavior of the entire transducer arrangement are the same for the directional characteristics comprising the two frequency bands.
  • the transducer group of transducers used to form the directional characteristic in the next higher frequency band are required, are arranged in the same way between the transducers already existing in length, with downstream filters matched to the corresponding frequency band ensuring that only signals from these transducers in the corresponding frequency band are used to form the directional characteristic.
  • the particular advantages of the transducer arrangement according to the invention consist not only in the fact that the directional characteristic has the same properties with respect to the opening angle and secondary lobe behavior in the entire frequency range, but also in the fact that the space requirement of such a transducer arrangement is determined solely by the lower limit frequency of the frequency range.
  • a directional characteristic is obtained for each converter group in a directional generator downstream of the filters with the same passband, for example by delay or phase compensation.
  • the outputs of all directional formers are connected to a summing stage in which the directional characteristics for each frequency band are superposed and a directional characteristic with a constant opening angle and secondary lobe behavior is formed for the entire frequency range.
  • the advantage of frequency-separated direction formation and subsequent superimposition is that the filters have the same properties with respect to the amplitude and phase response for each frequency band, so that compensation can be easily set in any direction angle in any direction generator.
  • the entire multitude of transducers on the transducer arrangement is reduced by the further development according to the invention.
  • Selected transducers of a higher frequency band would have to be provided at locations where transducers of a transducer group of a lower frequency band are already arranged, so that these transducers can be assigned to both transducer groups.
  • Signals of these selected transducers are frequency-divided according to the advantageous development according to claim 3 to form the directional characteristic.
  • transducer arrangement according to claim 4, only a single direction generator is required, since the transducers of the same transducer group are arranged symmetrically to the right and left of the central transducer.
  • the middle converter is assigned to all converter groups.
  • a particularly advantageous embodiment of the converter arrangement according to the invention is specified in claim 6.
  • the division into octaves doubles the frequency band and halves the distance between the transducers of the associated transducer groups.
  • Transducers assigned to the transducer group corresponding to the lowest octave in the frequency band belong thus also to transducer groups correspondingly higher octaves, since they are arranged in squares which correspond to even-numbered fractions of the maximum transducer distance, so that the multitude of transducers is further reduced over the entire length of the transducer arrangement.
  • Each transducer that belongs to several transducer groups is followed by filters, the pass band of which includes the corresponding octaves.
  • Claim 7 specifies an advantageous development of the transducer arrangement according to the invention, with which such an improvement can be separated for each frequency band in a simple manner and can thus be carried out individually.
  • the invention is based on exemplary embodiments shown in the drawing for a transducer arrangement for transmitting and / or receiving sound waves within a wide range Frequency range shown.
  • the assignment of the length L 1 with transducers determines the secondary lobe behavior of the transducer arrangement or its directional characteristic.
  • the distance between the transducers depends on the smallest wavelength to be evaluated and is at most as large as half the wavelength in order to obtain clear direction finding results.
  • the upper limit frequency of 1000 Hz in the lower frequency band F1 determines the maximum transducer distance d1 and thus the transducer assignment over the length L1.
  • Each of the four transducers 11, 12, 13, 14 of this transducer group is followed by a filter 111, 112, 113, 114 with bandpass behavior which is tuned to the frequency band F 1, followed by a directional generator 150.
  • the direction generator 150 ensures the time delay of the received signals from the converters at the output of the filters 111 to 114 in accordance with the desired directional characteristic.
  • a transmission signal is fed into the directional generator and shifted in time with respect to one another.
  • Outputs of the directional generator are followed by n filters 111 to 114, which are tuned to the lower frequency band F 1 and are connected to the n converters 11, 12, 13, 14.
  • the ratio / L according to G1. (2) is the same for both groups of transducers 11 to 14 and 21 to 24 and is
  • Each of these converters 21, 22, 23, 24 is followed by a filter 221, 222, 223, 224, which is tuned to the frequency band F2 and has bandpass behavior.
  • a directional generator 151 the directional characteristic for the frequency band F2 is formed.
  • Each of the transducers 31 to 34 is followed by a filter 311 to 314, which is tuned to the frequency band F3.
  • the filters 311 to 314 are followed by a direction generator 152.
  • the direction formers 150, 151, 152 are connected to a summing circuit 400.
  • the directional characteristic signal at the output of the summing circuit 400 has constant properties with respect to the opening angle ⁇ and secondary lobe behavior for different swivel angles over the frequency range from 500 to 8000 Hz.
  • the converter arrangement is simplified when the frequency range is divided into octaves.
  • 2 shows such a converter arrangement for a directional characteristic within a frequency range from 250 to 2000 Hz
  • ⁇ f1 250 to 500 Hz
  • ⁇ f2 500 to 1000 Hz
  • ⁇ f3 1000 to 2000 Hz, each comprising an octave.
  • ⁇ f1 250 to 500 Hz
  • ⁇ f2 500 to 1000 Hz
  • ⁇ f3 1000 to 2000 Hz
  • a predefined secondary lobe behavior is realized by appropriately assigning the transducer arrangement.
  • the maximum transducer distance d 1.5 m is selected as the transducer distance.
  • the number n 5 is determined from the length L and the transducer distance d.
  • Two transducers 1001 and 1002 are arranged at a distance d and two transducers 1003 and 1004 are spaced 2d symmetrically to a transducer 1000 placed in the center.
  • the transducers 1000 to 1004 form a transducer group and are connected to filters 1010 to 1014 which pass the lowest frequency band ⁇ f 1.
  • a converter 1005 is arranged between the middle converter 1000 and the converter 1001, and a converter 1006 is arranged between the converters 1000 and 1002, each of which relates to the center converter 1000 Have distance d / 2.
  • the centrally located transducer 1000 and the transducers 1001 and 1002 not only belong to the first transducer group, but also to this second transducer group, since they are arranged in multiples of the transducer distance d / 2 from the centrally located transducer 1000.
  • the five converters 1000, 1001, 1002, 1005, 1006 thus form the second converter group. They are each followed by filters 2010 to 2014, which are tuned to the frequency band ⁇ f2.
  • a transducer group of five transducers 1000, 1005, 1006, 1007, 1008 is also provided on the transducer arrangement, the distance d / 4 of which is a quarter of the maximum transducer distance d because the upper limit frequency of 2000 Hz of this frequency band ⁇ f3 four times as high as the upper limit frequency of 500 Hz of the lowest frequency band ⁇ f1.
  • the middle converter 1000 thus belongs to all groups.
  • a third filter 3010 which is tuned to the frequency band ⁇ f3.
  • the transducers 1005 and 1006 belong to two transducer groups.
  • the filters 1010 to 3014 contain evaluation circuits for Shading factors. Depending on the frequency band and the geometric position of the transducer, shading factors are stored in the evaluation circuits, with which the filtered received signals are multiplied before the direction is formed.
  • the direction formation is simplified insofar as individually selected transducers 1000, 1001, 1002, 1005, 1006 are assigned to several transducer groups and their received signals require the same time delays to form the directional characteristic.
  • Received signals from the selected converters 1000, 1001, 1002, 1005, 1006 are combined at the output of the filters 1010, 2010, 3010 or 1011, 2011 or 1012, 2012, ... in summing stages 4010, 4011, ..., 4014 , before they are further processed in a downstream direction generator 4400 for directional characteristics.
  • a circuit arrangement according to DE-PS 21 36 780, for example, can be used as the direction generator 4400.
  • the received signal of the converter 1000 is combined in the entire frequency range after a frequency-dependent evaluation.
  • Rated reception signals from the transducers 1001 and 1002, which belong to both the first and the second transducer group, are combined in the summing stages 4011 and 4012 for the two frequency bands ⁇ f1 and ⁇ f2.
  • the evaluated reception signals of the converters 1005 and 1006 for the frequency bands ⁇ f2 and ⁇ f3 are added.
  • the two outer transducers 1003 and 1004 only belong to the transducer group that is required for direction formation in the lowest frequency band ⁇ f 1.
  • the converters 1007 and 1008 belong to that Transducer group, their evaluated received signals are fed directly into the direction generator 4400.
  • a directional characteristic signal can be taken off at the output of the directional generator 4400 and has the same properties at different swivel angles over the entire frequency range.

Claims (7)

  1. Dispositif à transducteurs pour réaliser l'émission et/ou la réception dirigée d'ondes acoustiques à l'intérieur d'une plage étendue de fréquences, comportant une multiplicité de transducteurs rangés sur une certaine longueur et des filtres branchés en aval des transducteurs et dont les signaux de sortie sont réunis pour former une caractéristique directionnelle, caractérisé en ce que respectivement un nombre égal (n) de transducteurs (11 à 14 ou 21 à 24 ou 31 à 34 ou 1000 à 1004 ou 1000, 1001, 1002, 1005, 1006 ou 1000, 1005, 1006, 1007, 1008) parmi la multiplicité de transducteurs forment un groupe de transducteurs, qu'à chaque groupe de transducteurs est associée une bande de fréquences (F₁,F₂,F₃ ou Δf₁, Δf₂, Δf₃) à l'intérieur de la plage de fréquences, les bandes de fréquences (F₁,F₂,F₃ ou Δf₁, Δf₂, Δf₃) étant contiguës et couvrant la plage de fréquences, que les transducteurs (11 à 14 ou 1000 à 1004) sont disposés d'une manière équidistante à l'intérieur d'un groupe de transducteurs, en étant séparés par une distance égale ou inférieure à la moitié de la longueur d'onde la plus petite contenue dans la bande respective de fréquences (F₁ ou Δf₁), que le nombre (n) des transducteurs (11 à 14, 21 à 24, 31 à 34 ou 1000 à 1008) associés à un groupe de transducteurs est déterminé par la longueur (L₁ ou L) et par la distance maximale (d₁ ou d) entre les transducteurs du groupe de transducteurs associé à la bande la plus faible de fréquences (F₁ ou Δf₁), et que les filtres (111 à 114, 211 à 214, 311 à 314 ou 1010 à 1014, 2010 à 2014, 3010 à 3014), qui sont raccordés à des transducteurs (11 à 14, 21 à 24, 31 à 34 ou 1000 à 1004, 1000, 1001, 1002, 1005, 1006, ou 1000, 1005, 1006, 1007, 1008) du même groupe de transducteurs sont accordés sur la bande de fréquences (F₁, F₂, F₃ ou Δf₁, Δf₂, Δf₃) associée à ce groupe de transducteurs.
  2. Dispositif à transducteurs selon la revendication 1, caractérisé en ce que des transducteurs sélectionnés (1000, 1001, 1002, 1005, 1006) sont associés à plusieurs groupes de transducteurs, dont les bandes de fréquences associées (Δf₁, Δf₂, Δf₃) sont des multiples les unes des autres.
  3. Dispositif à transducteurs selon la revendication 2, caractérisé en ce qu'en aval de chaque transducteur sélectionné (1000 ou 1001, 1002 ou 1005,1006) sont branchés, en fonction de l'appartenance du transducteur à un groupe de transducteurs, plusieurs filtres (1010,2010,3010 ou 1011,2011,1012,2012 ou 2013,3013,2014,3014) accordés sur les bandes associées de fréquences (Δf₁,Δf₂,Δf₃ ou Δf₁,Δf₂ ou Δf₂,Δf₃).
  4. Dispositif à transducteurs suivant l'une des revendications 1 à 3, caractérisé par le fait que les transducteurs (1001 à 1004 ou 1001,1002,1005,1006 ou 1005 à 1008) de chaque groupe de transducteurs sont symétriques par rapport à un transducteur (1000) installé en position centrée, et que le transducteur (1000) disposé en position centrée est associé à tous les groupes de transducteurs.
  5. Dispositif à transducteurs suivant l'une des revendications 1 à 4, caractérisé par le fait que les distances différentes dans le groupe de transducteurs possèdent respectivement la même fraction de la plus petite longueur d'onde dans la bande associée de fréquences (F₁ à F₃ ou Δf₁ à Δf₃).
  6. Dispositif à transducteurs suivant l'une des revendications 1 à 5, caractérisé par le fait qu'à chaque groupe de transducteurs est associée une octave en tant que bande de fréquences (Δf₁, Δf₂, Δf₃), que les distances (d) des transducteurs (1000 à 1004) du groupe de transducteurs associé à l'octave la plus basse (Δf₁) sont maximales et que les distances (d/2 ou d/4) dans les groupes de transducteurs associés à l'octave respective immédiatement supérieure (Δf₂ ou Δf₃) sont égales à la moitié de la distance présente dans le groupe de transducteurs qui est associé à l'octave inférieure (Δf₁ ou Δf₂).
  7. Dispositif à transducteurs suivant l'une des revendications 1 à 6, caractérisé par le fait que chaque filtre (111 à 114, 211 à 214, 311 à 314 ou 1010 à 1014, 2010 à 2014, 3010 à 3014) contient un circuit de pondération pour des facteurs d'ombrage en fonction de la position du transducteur (11 à 14, 21 à 24, 31 à 34 ou 1000 à 1008) à l'intérieur du groupe de transducteurs.
EP87113165A 1986-10-06 1987-09-09 Disposition de transducteurs Expired - Lifetime EP0263314B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863633991 DE3633991A1 (de) 1986-10-06 1986-10-06 Wandleranordnung
DE3633991 1986-10-06

Publications (3)

Publication Number Publication Date
EP0263314A2 EP0263314A2 (fr) 1988-04-13
EP0263314A3 EP0263314A3 (en) 1988-07-27
EP0263314B1 true EP0263314B1 (fr) 1991-12-18

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ID=6311151

Family Applications (1)

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EP87113165A Expired - Lifetime EP0263314B1 (fr) 1986-10-06 1987-09-09 Disposition de transducteurs

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EP (1) EP0263314B1 (fr)
DE (2) DE3633991A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4422234C1 (de) * 1994-06-24 1995-08-24 Stn Atlas Elektronik Gmbh Schaltanordnung für eine Schleppantenne
US6526147B1 (en) 1998-11-12 2003-02-25 Gn Netcom A/S Microphone array with high directivity
DE102010056119B4 (de) * 2010-12-23 2015-02-05 Atlas Elektronik Gmbh Akustische Unterwasserantenne, U-Boot mit derartiger Antenne sowie Verfahren zum Peilen, Orten und/oder Klassifizieren eines Ziels mittels einer derartigen Antenne

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4241610A (en) * 1979-02-05 1980-12-30 Varian Associates, Inc. Ultrasonic imaging system utilizing dynamic and pseudo-dynamic focusing
JPS57203434A (en) * 1981-06-08 1982-12-13 Tokyo Shibaura Electric Co Ultrasonic diagnostic apparatus
US4569231A (en) * 1984-07-09 1986-02-11 General Electric Company Multiple frequency annular transducer array and system

Also Published As

Publication number Publication date
EP0263314A2 (fr) 1988-04-13
DE3633991A1 (de) 1988-04-14
DE3775322D1 (de) 1992-01-30
EP0263314A3 (en) 1988-07-27

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