Patent ID: 11949479
Assignee: NOKIA TECHNOLOGIES OY
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 6:
7. Said method of claim 6, wherein the effective channel information H with a first stage precoding matrix F is given by:, H
   _
  
  =
  
   
    [
    ⁠
    
     
      
       
        
         v
         
          1
          ,
          1
         
         H
        
        ⁢
        
         H
         
          1
          ,
          1
         
        
        ⁢
        
         f
         1
        
       
      
      
       
        
         v
         
          1
          ,
          1
         
         H
        
        ⁢
        
         H
         
          1
          ,
          1
         
        
        ⁢
        
         f
         2
        
       
      
      
       …
      
      
       
        
         v
         
          1
          ,
          1
         
         H
        
        ⁢
        
         H
         
          1
          ,
          1
         
        
        ⁢
        
         f
         M
        
       
      
     
     
      
       ⋮
      
      
       ⋮
      
      
        
      
      
       ⋮
      
     
     
      
       
        
         v
         
          1
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          1
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         1
        
       
      
      
       
        
         v
         
          1
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          1
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         2
        
       
      
      
        
      
      
       
        
         v
         
          1
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          1
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         M
        
       
      
     
     
      
       
        
         v
         
          2
          ,
          1
         
         H
        
        ⁢
        
         H
         
          2
          ,
          1
         
        
        ⁢
        
         f
         1
        
       
      
      
       
        
         v
         
          2
          ,
          1
         
         H
        
        ⁢
        
         H
         
          2
          ,
          1
         
        
        ⁢
        
         f
         2
        
       
      
      
        
      
      
       
        
         v
         
          2
          ,
          1
         
         H
        
        ⁢
        
         H
         
          2
          ,
          1
         
        
        ⁢
        
         f
         M
        
       
      
     
     
      
       ⋮
      
      
       ⋮
      
      
       ⋱
      
      
       ⋮
      
     
     
      
       
        
         v
         
          2
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          2
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         1
        
       
      
      
       
        
         v
         
          2
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          2
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         2
        
       
      
      
        
      
      
       
        
         v
         
          2
          ,
          
           K
           1
          
         
         H
        
        ⁢
        
         H
         
          2
          ,
          
           K
           1
          
         
        
        ⁢
        
         f
         2
        
       
      
     
     
      
       ⋮
      
      
        
      
      
        
      
      
       ⋮
      
     
     
      
       
        
         v
         
          M
          ,
          
           K
           M
          
         
         H
        
        ⁢
        
         H
         
          M
          ,
          
           K
           M
          
         
        
        ⁢
        
         f
         1
        
       
      
      
       
        
         v
         
          M
          ,
          
           K
           M
          
         
         H
        
        ⁢
        
         H
         
          M
          ,
          
           K
           M
          
         
        
        ⁢
        
         f
         2
        
       
      
      
       …
      
      
       
        
         v
         
          M
          ,
          
           K
           M
          
         
         H
        
        ⁢
        
         H
         
          M
          ,
          
           K
           M
          
         
        
        ⁢
        
         f
         M
        
       
      
     
    
    ]
   
   =
   
    
    
     
      [
      
       
        
         
          
           
            H
            _
           
            
          
          1
         
        
       
       
        
         
          
           
            H
            _
           
            
          
          2
         
        
       
       
        
         ⋮
        
       
       
        
         
          
           H
           _
          
          M
         
        
       
      
      ]
     
     ,
    
   
  
 

wherein H is a matrix with a dimension of K×M, m=1, 2, . . . , M and k=1, 2, . . . , K; vm, k is the receiving beamforming vector for the k-th user in the m-th group, and Hm,k is the channel information for the k-th user in the m-th group,
fm is the m-th column vector of the first stage precoding matrix F in corresponding to user equipments in the m-th group, and to each Hm in the equation for H, Hm contains Km×M elements;
and with singular vector decomposition to the following matrix:, H
     ˆ
    
    m
   
   =
   
    
     [
     
      
       
        
         
          H
          _
         
         1
        
       
      
      
       
        ⋮
       
      
      
       
        
         
          H
          _
         
         
          m
          ⁢
          ‐
          ⁢
          1
         
        
       
      
      
       
        
         
          H
          _
         
         
          m
          +
          1
         
        
       
      
      
       
        ⋮
       
      
      
       
        
         
          H
          _
         
         M
        
       
      
     
     ]
    
    =
    
     
      U
      m
     
     ⁢
     
      
       ∑
       m
      
      
       
        [
        
         
          
           
            
             V
             m
             
              (
              1
              )
             
            
             
           
          
          
           
            V
            m
            
             (
             0
             )
            
           
          
         
        
        ]
       
       H
      
     
    
   
  
  ,
 

where Pm at the m-th group is obtained through, H
     _
    
    m
   
   ⁢
   
    
     ∑
     
      
       i
       =
       1
      
      ,
      
       i
       ≠
       m
      
     
     M
    
    
     
      P
      i
     
     ⁢
     
      
       s
       ¯
      
      i
     
    
   
  
  =
  0, wherein Vm(1) denotes the first r right singular vectors, where r is the rank of matrix Ĥm and Vm(0) is the last M−r singular vector, and {tilde over (s)}i denotes the i-th signal vector to be transmitted.