Patent ID: 11967829
Assignee: UIF (UNIVERSITY INDUSTRY FOUNDATION), YONSEI UNIVERSITY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. The channel estimating apparatus according to claim 7, wherein the transmitting channel updating unit calculates the gradient

∇h(G)

by Equation 7,, ∇
       
        h
        ⁡
        (
        G
        )
       
      
      =
      
       
        ∑
        
         k
         =
         1
        
        K
       
       
        
         
          ∑
           
         
         
          l
          =
          1
         
         L
        
        ⁢
        
         2
         [
         
          
           
            
             (
             
              
               β
               k
               
                2
                ⁢
                
                 (
                 
                  l
                  -
                  L
                 
                 )
                
               
              
              -
              1
             
             )
            
            ⁢
            
             w
             ⁡
             (
             
              l
              ′
             
             )
            
            ⁢
            
             
              w
              H
             
             (
             
              l
              ′
             
             )
            
            ⁢
            G
           
           
            (
            
             
              σ
              k
              2
             
             +
             
              
               (
               
                
                 β
                 k
                 
                  2
                  ⁢
                  
                   (
                   
                    l
                    -
                    L
                   
                   )
                  
                 
                
                -
                1
               
               )
              
              ⁢
              
               
                
                
                 
                  
                   w
                   H
                  
                  (
                  
                   l
                   ′
                  
                  )
                 
                 ⁢
                 G
                
                
               
               2
              
             
            
            )
           
          
          -
          
           
            
             (
             
              
               β
               k
               
                2
                ⁢
                
                 (
                 
                  l
                  -
                  L
                 
                 )
                
               
              
              -
              1
             
             )
            
            ⁢
            
             w
             ⁡
             (
             
              l
              ′
             
             )
            
            ⁢
            
             
              w
              H
             
             (
             
              l
              ′
             
             )
            
            ⁢
            G
           
           
            
             (
             
              (
              
               
                σ
                k
                2
               
               +
               
                
                 (
                 
                  
                   β
                   k
                   
                    2
                    ⁢
                    
                     (
                     
                      l
                      -
                      
                       1
                       ⁢
                       L
                      
                     
                     )
                    
                   
                  
                  -
                  1
                 
                 )
                
                ⁢
                
                 
                  
                  
                   
                    
                     w
                     H
                    
                    (
                    
                     l
                     ′
                    
                    )
                   
                   ⁢
                   G
                  
                  
                 
                 2
                
               
              
              )
             
             )
            
            2
           
          
          -
          
           
            (
            
             
              β
              k
              
               
                -
                L
               
               +
               1
              
             
             ⁢
             
              w
              ⁡
              (
              
               l
               ′
              
              )
             
             ⁢
             
              
               (
               
                h
                k
               
               )
              
              H
             
             ⁢
             
              θ
              ⁡
              (
              
               l
               ′
              
              )
             
             ⁢
             
              (
              
               
                
                 
                  r
                  k
                 
                 (
                 
                  l
                  ′
                 
                 )
                
                ⁢
                
                 e
                 
                  j
                  ⁢
                  
                   
                    θ
                    k
                   
                   (
                   
                    l
                    ′
                   
                   )
                  
                 
                
               
               -
               
                
                 β
                 k
                 
                  
                   -
                   L
                  
                  +
                  1
                 
                
                ⁢
                
                 
                  w
                  H
                 
                 (
                 
                  l
                  ′
                 
                 )
                
                ⁢
                G
                ⁢
                
                 
                  θ
                  H
                 
                 (
                 
                  l
                  ′
                 
                 )
                
                ⁢
                
                 h
                 k
                
               
              
              )
             
            
            )
           
           
            (
            
             
              σ
              k
              2
             
             +
             
              
               (
               
                
                 β
                 k
                 
                  2
                  ⁢
                  
                   (
                   
                    l
                    -
                    L
                   
                   )
                  
                 
                
                -
                1
               
               )
              
              ⁢
              
               
                
                
                 
                  
                   w
                   H
                  
                  (
                  
                   l
                   ′
                  
                  )
                 
                 ⁢
                 G
                
                
               
               2
              
             
            
            )
           
          
         
         ]
        
       
      
     
     ,
     
      
       l
       ′
      
      =
      
       T
       -
       L
       +
       1
      
     
     ,
    
   
   
    
     [
     
      Equation
      ⁢
         
      7
     
     ]
    
   
  
 

where σk2 is a standard deviation of a Gaussian noise between the transmitter and the k-th terminal.