Patent ID: 11962344
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. The method according to claim 7, wherein obtaining the first noise amount associated with the equalized electrical signal comprises:
determining the first noise amount σDUT_estimated associated with the equalized electrical signal according to the following:, 1
     2
    
    ⁢
    
     (
     
      
       ∫
       
        
         
          
           f
           u
          
          (
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         ·
         
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              M
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              DUT
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       ∫
       
        
         
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     1
     2
    
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  =
  
   BER
   
    t
    ⁢
    a
    ⁢
    r
    ⁢
    g
    ⁢
    e
    ⁢
    t
   
  
 

wherein y represents a signal power collected at a sampling point at which the sampled electrical signal is located, Pth represents the average optical power, fu(y) is amplitude distribution at a sampling point at which an optical power is greater than Pth, fl(y) is amplitude distribution at a sampling point at which an optical power is less than Pth, M(y) represents the modified noise ratio parameter, Ceq is the noise enhancement factor, BERtarget is a bit error rate threshold, and Q represents a tail function with standard normal distribution.