Patent ID: 11959799
Assignee: ASELSAN ELEKTRONIK SANAYI VE TICARET ANONIM SIRKETI
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 2:
3. The phase sensitive optical time domain reflectometry based distributed acoustic sensing system according to the claim 2, wherein the optical pulse p(t) is simplified as follows:, p
      ⁡
      
        (
        t
        )
      
    
    =
    
      
        ∑
        
          k
          =
          
            -
            ∞
          
        
        ∞
      
      ⁢
      
        
      
      ⁢
      
        [
        
          
            
              f
              ⁡
              
                (
                t
                )
              
            
            ⁢
            
              Π
              ⁡
              
                (
                
                  
                    t
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                      p
                    
                  
                  
                    T
                    w
                  
                
                )
              
            
          
          +
          
            ϵ
            ⁡
            
              (
              
                
                  f
                  ⁡
                  
                    (
                    t
                    )
                  
                
                +
                
                  g
                  ⁡
                  
                    (
                    t
                    )
                  
                
              
              )
            
          
        
        ]
      
    
  
  ,

when extinction ratios are similar and ϵ=ϵ1≈ϵ2<<1, thus the phase sensitive optical time domain reflectometry based distributed acoustic sensing system becomes an interrogation unit using the optical pulse with two states, comprising a coherent ON state and an incoherent OFF state.