DD288729A7 - METHOD FOR LOCATING A WAFER SOIL - Google Patents

Abstract

The invention can be applied in all areas of hydro-positioning, where it is located by the sonar method. It is the object of the invention to find out the ground echo from the received echoes (Stoerechos, Ground echoes, Stoemehrechechos and ground multiple echoes) with higher security. The invention has for its object to develop a method that makes it possible to automatically determine the distance between a vibrator and the bottom of a Gewaessers with elimination of Stoerechos, soil and Schoermehrfachechos at unfavorable Lotbedingungen. According to the invention, the object is achieved by using the measured and stored transit times, preferably all echoes during a soldering period or the mean values of the transit times, preferably all echoes, during several soldering periods to calculate the expected transit times of possible multiple echoes. These calculated transit times are compared with the actually measured ones. Upon agreement, an echo margin comparison is made between the echoes and supposed multiple echoes. In the event that the echo amounts are the same, the putative multiple echoes are identified as multiple echoes and eliminated. Of the remaining echoes, this is rated as the ground echo with the largest runtime and thus the depth of the river can also be determined. The advantage of this method is that ground echoes from Stoerechos and multiple echoes can be distinguished with high certainty even if the echo and multiple echo meet all the criteria of a ground echo or a bottom echo does not meet this criterion.

Description

Ausführungsbolsplel Reference to an embodiment of the invention will be explained in more detail. Fig. 1 shows a block diagram for the realization of the method. Fig. 2 shows the possible Laufzoitverhältnisse of false echoes and ground echo during a Lotperiode. 3 shows the possible Laufzeltverhältnlseo of false echoes, bottom echo and Bodonmohrechechos during a Lotperiode. 4 shows the possible delay ratios of false echoes, bottom echo and multiple echo during a soldering period.

FIG. 5 shows the possible transit time ratios of false echoes, ground echo as well as interference multiple echoes during a soldering period.

With the help of the echo sounder 1 disturbing reflection objects and the water bottom are located and measured the duration of the echoes and the multiple echoes from there and stored. The values of the transit times are fed to the computer 2. In the computer, first the expected tenths of possible multiple echoes according to the terms of the sequence to the echo with the shortest duration

2t _L , (2t _L + t _LT ), 3t _tl (3t _L + 2t _LT ), ... nt _L , (nt _L + (n - 1) t _LT ) (D

t _L - measured echo time or mean of the measured, tread tu - echo time water surface oscillator

calculated.

The echo time is too

with Tg - draft of the ship and C - sound velocity.

Taking into account the criterion that the presence of an η-th multiple echo is bound to the presence of a (n-1 Hen multiple echo, the comparison with the smallest term is carried out beginning until no more apparent multiple echoes are present.

If a calculated term is equal to a runtime in a plant and operational tolerance, then the echo length dos echo with which the terms are calculated are compared with the echo length of the supposed multiple echo. For the FtII that they are the same, the supposed multiple echo is identified as such. Subsequently, in the computer with the next runtime of the echo, which has not yet been characterized as multiple echo, the Tenne of the sequence (1) is formed and proceeded in the manner described above. This is done until the runtime of the penultimate echo, which has not yet been marked as multiple echo. In the end, all of the acclaimed maturities resulting from multiple echoes are eliminated. Of the remaining terms, taking into account that as a rule the duration of the ground echo is greater than the maturity of false echoes, these are eliminated, so that the duration of the ground echo remains with a high degree of certainty. In computer 2, the distance from the ground is determined with this transit time and the speed of sound. The value of this distance is then given to the display device 3 and displayed there. The following runtime ratios and thus also process states can occur:

1. According to FIG. 2

The terms 2t _LSI , (2t _LS , + t _LT ), 3t _actual , (3t _{LS 1} + 2t _LT ), 2t _LS2 , (2t _tS 2 + <lt) are formed. Since all comparisons of the calculated duration of the multiple echoes with the measured transit times to a match

The echo EB with the transit time ti _{B is} the bottom echo, and echoes ES 1 and ES2 are false echoes.

2. NachFig.3

These runtime ratios represent the rule when interference and multiple _{echoes occur} . 5-, first the terms 2 t _L si, (2t _ls , + t _LT >, 3t _LS1 , (3t _lS i + 2t _LT ), 4t _LS1 , (4t _ls , + 3t _lT ), 5t _LS1 , (5t _ls1 + 4t _LT ), 2t _lS2 , (2t _LS2 + t _LT ), 3t _LS 2, (3t _LS2 + 2t _LT ), 4t _lS2 , (4t _LS2 + 3t _LT ).

Since here too all comparisons of the calculated multiple _echoes with the measured transit times do not lead to a match, with the next transit time t _tB the terms 2t _lB , (2t _LB + t _lT ), 3t _LB , (3t _lB + 2t _LT ) are formed.

Here is first match of the term 2 t |. _B with the term of the supposed multiple echo E _B Mu determined. Since the subsequent echo length comparison between E ₈ and E _D mh results in a match of the compared echo lengths within an analog and operational tolerance, this supposed multiple echo is characterized as multiple echo. Next, agreement of the term (2t _LB + tu) with the term of the supposed multiple echo E _B mi2 is determined. The subsequent echo length comparison is similar to E _BM1 . Thus, E _BM i ₂ is also marked as multiple echo. The echoes E _BMn and E _BM12 marked as multiple echoes are eliminated, and thus the echo E ₈ with the transit time Iw is the ground echo with high reliability.

3. AfterFig.4

The same terms are formed as in FIG. In this case, additional E _SMn , E ₅ Mi ₂ , Esmji and Esm _{22 are identified} as multiple echoes of false echoes E ₅ , and E ₅₂ . With high certainty then the echo E _{0 is} the bottom echo.

4. According to FIG. 5

The terms become 2t _LS) , (2t _ls , + t _LT ). 3t _LS1 , (3t _LS i + 2t _LT ), 4t ,. _s ,, (4t _ls , + 3t _LT ), 2t _lS2 , (2t _LS2 + t _LT ), 3t _LS2 , (3t _LS2 + 2tu), 2t _lB , (2t _L B + tu). Apart from the multiple echoes E _d mii and E ₀ M-.2, the same multiple echoes as in FIG. 4 are eliminated here. With great certainty, the echo E _{B is} the bottom echo.

Claims (1)

Method for locating a watercourse, characterized in that the expected transit times of possible multiple echoes are calculated using the measured and stored transit times of preferably all echoes during a soldering period or the mean values of the transit times of all echoes during a plurality of solder bumps and these calculated transit times are actually measured and gospeichert runtimes are compared and if they match within an investment and operational tolerance echolength comparison between the echoes with which the matching in the term multiple echoes were calculated, and don associated alleged multiple echoes is performed, wherein in the event that the echo lengths compared with are equal to a plant and operational tolerance, the putative multiple echo is characterized as multiple echo and eliminated, and of the remaining echoes then the one with the largest lau fzeit as bottom echo is scored and the rest are marked as false echoes and eliminated. For this 3 pages drawings Field of application of the invention The invention can be applied in all areas of hydro-positioning, where it is located by the sonar method. Characteristic of the known technical solutions As is known, an acoustic echo from the bottom of a body of water usually differs from other echoes (caused by shoals of fish, solitary fish, objects floating in the water, etc.), further called clutter, in that the echopogol is relatively large after a time-dependent amplification Echolength depending on the depth and opening angle of the vibrator and the movement of the vibrator maintains a certain size range and a high probability of the occurrence of ground echoes is guaranteed. However, the false echoes can also meet in some cases these criteria of a ground echo or the bottom echo does not meet these criteria in each case, so that the false echoes of ground echoes in the patents AS 1278892. AS 1766882, AS 1961748, OS 2010789, PS 2029311 , AS 2204352, OS 224081Γ, AS 2405099, AS 2735949 from the Federal Republic of Germany and GP GO01 S / 226319 not sufficiently safe! '. are distinguishable. Object of the invention It is the object of the invention to find out the ground echo from the received echoes (false echoes, bottom echo, interference multiple echoes and ground multiple echoes) with higher reliability. Explanation of the essence of the invention The invention has for its object to develop a method that allows to automatically determine the distance between a vibrator and the bottom of a body of water with elimination of false echoes, multiple ground echoes and Störmehrfachechos also for the cases in which false echoes, multi ground echoes and Störmehrfachechos the Meet criteria of a ground echo and the bottom echo does not meet these criteria. According to the invention the object is achieved in that don with a sonar system measured and stored maturities vorzugsweie all echoes during a Lotperriode or the average values of maturities preferably all echoes during several Lotperioden the expected running times η possible multiple echoes are calculated. Any echo time or mean value of the echo delay time may be from a false echo, multiple echo, bottom echo or ground echo. hecho. Therefore, each measured time or average of the echo times with all the calculated echo times is compared taking into account the criterion that the presence of an ηth multiple echo is bound to the presence of a (n-1) th echo. In case of equality in a system and operational tolerance, the echolength of the echo, with dt> m the multiple echo matching in transit time, is then compared with the echolength of the supposed multiple echo, and in case the echo lengths are equal with a system and operational tolerance are the supposed Mehrfachecho recognized as Mehrfachecho, marked and eliminated. Taking into account that the duration of the ground echo is usually greater than the duration of false echoes, the echo with the largest remaining duration can be considered as ground echo with great certainty. The advantage of this method is that ground echoes of false echoes and multiple echoes can be distinguished with high certainty even when the false echoes and multiple echoes meet all the criteria of a ground echo or a bottom echo does not meet these criteria.