Method for an equivalent circuit parameter estimation of a transducer and a sonar system using thereof

Abstract

The present disclosure relates to an active sonar system including a transmitter; a transducer; and an impedance matching circuit, and a method of estimating an equivalent model parameter of a multi-mode transducer, wherein an electrical equivalent model parameter having a plurality of stages corresponding to each mode is estimated by estimating an individual mode impedance and a total mode impedance from multi-mode impedance data and obtaining an interference amount of adjacent modes, and an equivalent model modeled thereby for which an interference effect by a multi-mode is taken into consideration is used for the design of an impedance matching circuit to minimize actual model fabrication and effectively derive detailed design elements and the like, thereby allowing an integrated circuit design with peripheral electronic units for interfacing the sonar system.

1 . A method of estimating an equivalent model parameter of a multi-mode transducer, wherein an electrical equivalent model parameter having a plurality of stages corresponding to each mode is estimated by estimating an individual mode impedance and a total mode impedance from multi-mode impedance data and considering an interference amount of adjacent modes. 
     
     
         2 . The method of  claim 1 , comprising:
 a resonant frequency derivation process of dividing a frequency section for divisions between resonant modes and obtaining a resonant frequency corresponding to each mode;   an individual mode impedance estimation process of removing an interference effect of adjacent modes within the divided mode section to obtain an impedance for each mode; and   a multi-mode impedance estimation process of considering even a multi-mode impedance characteristic in which individual modes are combined to have an effect on one another.   
     
     
         3 . The method of  claim 2 , further comprising:
 an interference amount derivation process of quantitatively deriving an interference effect between adjacent modes; and   a resonant frequency failure correction process of correcting a failure of the resonant frequency from the interference amount.   
     
     
         4 . The method of  claim 2 , wherein the resonant frequency derivation process divides a frequency section for each mode by a minimum point of the conductance from impedance data, and derives a maximum point as a resonant frequency of the relevant mode. 
     
     
         5 . The method of  claim 2 , wherein the individual mode impedance estimation process comprises:
 an individual mode impedance computation process of removing an interference component combined with a k-th resonant mode from a measured total admittance and computing a k-th individual mode impedance; and   a fitness function generation process of displaying an error average between the computed k-th individual mode impedance and a k-th resonant mode impedance to be estimated as a fitness function (B k ) to be minimized in the relevant mode section.   
     
     
         6 . The method of  claim 2 , wherein the multi-mode impedance estimation process estimates a total impedance for which impedance estimation values of individual modes for a multi-mode equivalent model are combined, and generates it as another fitness function (A) to minimize an error from the measured impedance. 
     
     
         7 . The method of  claim 3 , wherein the resonant frequency failure correction process corrects a resonant frequency in the direction of its differential values being the same when a differential value of a total measured conductance is different from a sum of differential values for interfered adjacent mode conductances at the computed resonant frequency. 
     
     
         8 . The method of  claim 5 , wherein a resultant fitness function (F) is expressed as: 
       
         
           
             
               F 
               = 
               
                 
                   
                     C 
                     1 
                   
                    
                   A 
                 
                 + 
                 
                   
                     C 
                     2 
                   
                    
                   
                     
                       ∑ 
                       
                         k 
                         = 
                         1 
                       
                       N 
                     
                      
                     
                       B 
                       k 
                     
                   
                 
               
             
           
         
         by applying weight constants (C 1 , C 2 ) to take an item for minimizing the individual mode estimation error and an item for minimizing an total mode estimation error into consideration at the same time. 
       
     
     
         9 . An active sonar system, comprising:
 a transmitter modeled as an input power source and an input impedance;   a transducer configured to convert an electrical signal of the transmitter into an acoustic wave or convert an acoustic wave of the outside into an electrical signal; and   an impedance matching circuit configured to transmit the electric power of the transmitter to the transducer between the transmitter and transducer,   wherein the transducer is modeled as an electrical equivalent model parameter having a plurality of stages corresponding to each mode by estimating an individual mode impedance and a total mode impedance from multi-mode impedance data and considering an interference amount of adjacent modes.   
     
     
         10 . The active sonar system of  claim 9 , wherein the transducer is modeled to estimate a multi-mode impedance by dividing a frequency section for divisions between resonant modes and obtaining a resonant frequency corresponding to each mode, and removing an interference effect of adjacent modes within the divided mode section to obtain an impedance for each mode, and considering even a multi-mode impedance characteristic in which individual modes are combined to have an effect on one another in an integrated manner. 
     
     
         11 . The active sonar system of  claim 9 , wherein the transducer is modeled by quantifying an interference effect between adjacent modes and correcting a failure of the resonant frequency. 
     
     
         12 . The active sonar system of  claim 10 , wherein the transducer is modeled by dividing a frequency section for each mode by a minimum point of the conductance from impedance data, and deriving a maximum point as a resonant frequency of the relevant mode. 
     
     
         13 . The active sonar system of  claim 10 , wherein the transducer is modeled by removing an interference component combined with a k-th resonant mode from a measured total admittance and computing a k-th individual mode impedance, and generating an error average between the computed k-th individual mode impedance and a k-th resonant mode impedance to be estimated as a fitness function (B k ) to be minimized in the relevant mode section 
     
     
         14 . The active sonar system of  claim 10 , wherein the transducer is modeled by estimating a total impedance for which impedance estimation values of individual modes for a multi-mode equivalent model are combined, and generating it as another fitness function (A) to minimize an error from the measured impedance. 
     
     
         15 . The active sonar system of  claim 11 , wherein the transducer is modeled by correcting a resonant frequency in the direction of its differential values being the same when a differential value of a total measured conductance is different from a sum of differential values for interfered adjacent mode conductances. 
     
     
         16 . The method of  claim 6 , wherein a resultant fitness function (F) is expressed as: 
       
         
           
             
               F 
               = 
               
                 
                   
                     C 
                     1 
                   
                    
                   A 
                 
                 + 
                 
                   
                     C 
                     2 
                   
                    
                   
                     
                       ∑ 
                       
                         k 
                         = 
                         1 
                       
                       N 
                     
                      
                     
                       B 
                       k 
                     
                   
                 
               
             
           
         
         by applying weight constants (C 1 , C 2 ) to take an item for minimizing the individual mode estimation error and an item for minimizing an total mode estimation error into consideration at the same time.