Method for determining the direction of a source of waterborne sound, a computer program product, a computer or sonar, and a watercraft

1. A method for determining the direction of a source of waterborne sound that emits a waterborne acoustic signal by means of a hydrophone arrangement which forms a linear antenna or a virtual linear antenna, wherein the method comprises the following steps:

determining the waterborne acoustic signal incoming at the hydrophone arrangement at a first measurement time t 1 ,

performing an electronic antenna swing analysis which determines a sum signal S of the linear antenna or of the virtual signal antenna at every rotation angle αn=α0±nΔα, where α0 is the starting angle, Δα is the step-width angle, and n=0, 1, 2, 3, 4 . . . , such that a measurement series S(α) is created,

determining a maximum sum signal, S max (α max ), where α max represents the maximum rotation angle of the measurement series S(α),

determining a fit measurement series S Fit (α), which includes the maximum sum signal S max (α max ) and at least two more sum signals S(α n ) m , with the sum number m=2, 3, 4 . . . ,

determining a mathematical fit function S Fit (α Fit ) for the fit measurement series S Fit (α) by means of a mathematical equalization calculation, and

determining a fit function maximum f Fit,Max (α Fit,Max ) of the mathematical fit function f Fit (α Fit ), wherein the direction of the waterborne sound source can be determined by means of α Fit,Max .

2. Method according to claim 1 , wherein the procedure or sub-steps of the procedure can be carried out at a second measurement time t2, at a third measurement time t3, at a fourth measurement time t4, and/or at further times t, wherein the corresponding measurement series S(α) t or the determined directions of the waterborne sound source are averaged.

3. Method according to claim 2 , wherein the remaining steps of the procedure are carried out according to claim 1 .

4. Method according to claim 1 , wherein the additional sum signals are sum signals adjacent to the maximum sum signal S max (α max ).

5. Method according to claim 1 , wherein the mathematical fit function is a polynomial function, a Gaussian function, a Lorentz function, or a Voigt function.

6. An invention selected from the group consisting of:

(a) a computer program product which is set up so that the method according to claim 1 can be implemented with a computer or a sonar;

(b) a computer configured for carrying out a method according to claim 1 ;

(c) a sonar system for determining a direction of a source of a waterborne sound, the system comprising:

an antenna, wherein the antenna includes a plurality of piezoceramic elements, wherein the piezoceramic elements are configured to:

detect the waterborne acoustic sound; and

generate, based on the waterborne acoustic sound, a voltage;

a control circuit communicatively coupled to the plurality of piezoceramic elements, wherein the control circuit is configured to:

receive, from the plurality of piezoceramic elements at multiple points in time, the voltage;

perform an electronic swing analysis at a plurality of rotation angles at the multiple points in time;

determine, based on the electronic swing analysis, a maximum sum signal;

determine a fit measurement series, wherein the fit measurement series includes the maximum sum signal and at least two additional sum signals;

determine, based on a mathematical equalization calculation and the fit measurement series, a mathematical fit function; and

determine, based on the mathematical fit function, the direction of the source of the waterborne sound; and

(d) a sonar system configured for carrying out a method according to claim 1 .

7. An invention according to claim 6 , wherein the invention is (b) a computer configured for carrying out a method according to claim 1 .

8. An invention according to claim 6 , wherein the invention is (d) a sonar system configured for carrying out a method according to claim 1 .

9. A watercraft which includes a sonar system configured for carrying out a method comprising the following steps:

determining the waterborne acoustic signal incoming at the hydrophone arrangement at a first measurement time t 1 ,

performing an electronic antenna swing analysis which determines a sum signal S of the linear antenna or of the virtual signal antenna at every rotation angle αn=α0±nΔα, where α0 is the starting angle, Δα is the step-width angle, and n=0, 1, 2, 3, 4 . . . , such that a measurement series S(α) is created,

determining a maximum sum signal S max (α max ), where α max represents the maximum rotation angle of the measurement series S(α),

determining a fit measurement series S Fit (α), which includes the maximum sum signal S max (α max ) and at least two more sum signals S(α n ) m , with the sum number m=2, 3, 4 . . . ,

determining a mathematical fit function f Fit (α Fit ) for the fit measurement series S Fit (α) by means of a mathematical equalization calculation, and

determining a fit function maximum f Fit,Max (α Fit,Max ) of the mathematical fit function f Fit (α Fit ), wherein the direction of the waterborne sound source can be determined by means of α Fit,Max .

10. An invention according to claim 6 , wherein the invention is (c) a sonar system for determining a direction of a source of a waterborne sound, the system comprising:

an antenna, wherein the antenna includes a plurality of piezoceramic elements, wherein the piezoceramic elements are configured to:

detect the waterborne acoustic sound; and

generate, based on the waterborne acoustic sound, a voltage;

a control circuit communicatively coupled to the plurality of piezoceramic elements, wherein the control circuit is configured to:

receive, from the plurality of piezoceramic elements at multiple points in time, the voltage;

perform an electronic swing analysis at a plurality of rotation angles at the multiple points in time;

determine, based on the electronic swing analysis, a maximum sum signal;

determine a fit measurement series, wherein the fit measurement series includes the maximum sum signal and at least two additional sum signals;

determine, based on a mathematical equalization calculation and the fit measurement series, a mathematical fit function; and

determine, based on the mathematical fit function, the direction of the source of the waterborne sound.

11. An invention according to claim 10 , wherein in (c) the at least two additional sum signals are adjacent to the maximum sum signal.

12. An invention according to claim 11 , wherein in (c) the at least two additional sum signals are symmetric about the maximum sum signal.

13. An invention according to claim 6 , wherein in (c) the mathematical fit function is one of a polynomial function, a Gaussian function, a Lorentz function, and a Voigt function.

14. An invention according to claim 6 , wherein in (c) the plurality of piezoceramic elements includes between 50 and 200 piezoceramic units.

15. An invention according to claim 6 , wherein in (c) the plurality of piezoceramic elements form a side-scan sonar antenna.

16. An invention according to claim 15 , wherein the side-scan sonar antenna is one of a linear antenna and a virtual linear antenna.

17. An invention according to claim 6 , wherein in (c) there is a common step width between each of the plurality of rotation angles.

18. An invention according to claim 17 , wherein in (c) the common step width is approximately two degrees.

19. An invention according to claim 6 , wherein in (c) a total rotation for the plurality of rotation angles is one hundred eighty degrees.

20. An invention according to claim 6 , wherein the invention is (α) a computer program product which is set up so that the method according to claim 1 can be implemented with a computer or a sonar.

21. A ship or a submarine having a sonar system for determining a direction of a source of a waterborne sound, wherein the sonar system comprises:

an antenna, wherein the antenna includes a plurality of piezoceramic elements, wherein the piezoceramic elements are configured to:

(a) detect the waterborne acoustic sound; and

(b) generate, based on the waterborne acoustic sound, a voltage;

a control circuit communicatively coupled to the plurality of piezoceramic elements, wherein the control circuit is configured to:

(i) receive, from the plurality of piezoceramic elements at multiple points in time, the voltage;

(ii) perform an electronic swing analysis at a plurality of rotation angles at the multiple points in time;

(iii) determine, based on the electronic swing analysis, a maximum sum signal;

(iv) determine a fit measurement series, wherein the fit measurement series includes the maximum sum signal and at least two additional sum signals;

(v) determine, based on a mathematical equalization calculation and the fit measurement series, a mathematical fit function; and

(vi) determine, based on the mathematical fit function, the direction of the source of the waterborne sound.

22. A ship or a submarine according to claim 21 , wherein the at least two additional sum signals are symmetric about the maximum sum signal.

23. A ship or submarine according to claim 21 , wherein the plurality of piezoceramic elements form a side-scan sonar antenna.