Patent ID: 8730765
Filing Date: 2014-05-20
Classification: G01S

Abstract:
1. A method for measuring a profile of the ground ( 6 ) by means of a transmitting arrangement ( 20 ) attached to a watercraft ( 2 ) for the targeted emission of sound signals into an underwater area ( 8 ) and by means of a receiving arrangement ( 28 ) attached to said watercraft ( 2 ) having at least two transducers for receiving the sound waves reflected by the profile of the ground ( 6 ) inside the underwater area ( 8 ), from which the transducers each generate a received signal ( 40 ; 42 ), which is sampled, digitised and stored at predefined sampling times and wherein a sound signal with a plurality N of predefined frequencies that are different from one another is successively emitted into the underwater area ( 8 ) by means of said transmitting arrangement ( 20 ) and components of said sound signal reflected by the profile of the ground ( 6 ) are received by means of the receiving arrangement ( 28 ) and the N different frequencies are filtered out of the received signal ( 40 ; 42 ), and wherein for a plurality of the sampling times and for the N frequencies of the received signals ( 48 1 , 48 2 , 48 3 , . . . , 48 N ; 50 1 , 50 2 , 50 3 , . . . , 50 N ), both a phase difference (Δφ) and a transit time (τ) of these received signals are determined, wherein