Patent ID: 11876568
Assignee: GENERAL TEST SYSTEMS INC.
Field: Telecommunications (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 4:
5. A tester, configured to:
obtain power level reporting information of a device under test;
obtain a propagation matrix based on the power level reporting information, and obtain an inverse matrix to be loaded based on the propagation matrix to form a virtual cable between an output port of an instrument and a receiver port of the device under test; and
transmit a throughput test signal through the virtual cable to perform a performance test on the device under test and obtain a test result of radio frequency performance,
wherein the tester is further configured to:
obtain an amplitude value based on the power level reporting information; and
obtain a phase difference of elements in the propagation matrix based on the amplitude value to obtain the propagation matrix,

the tester is further configured to:
transmit a first signal through a first test antenna to each receiver of the device under test, obtain power level reporting information of each receiver, and convert the power level reporting information into a first amplitude value of a received first signal received by each receiver, wherein the first amplitude value of the received first signal corresponds to the first test antenna;
transmit a second signal through a second test antenna to each receiver, obtain power level reporting information of each receiver, and convert the power level reporting information into a second amplitude value of a received second signal received by each receiver, wherein the second amplitude value of the received second signal corresponds to the second test antenna;
repeat the transmitting a signal, the obtaining the power level reporting information, and the converting the power level reporting information until the amplitude value of a received signal received by each receiver and corresponding to each test antenna is obtained;
transmit the first signal through the first test antenna and transmit the second signal through the second test antenna to each receiver simultaneously, obtain power level reporting information of each receiver of the device under test, determine an amplitude value of a synthesized signal received by each receiver, and obtain a phase difference between a received first signal received by each receiver and a received second signal received by each receiver based on the first amplitude value, the second amplitude value and the amplitude value of the synthesized signal; and
repeat transmitting signals by every two test antennas, obtaining the power level reporting information, determining the amplitude value of the synthesized signal, and obtaining the phase difference until the phase difference between received signals received by each receiver and corresponding to every two test antennas is obtained, so as to obtain the propagation matrix,

wherein obtaining the inverse matrix to be loaded based on the propagation matrix comprises:
expressing the propagation matrix based on a following equation:, P
     =
     
     
      [
      
       
        
         
          
           p
           11
          
          ⁢
          
           e
           
            j
            ⁢
            
             χ
             11
            
           
          
         
        
        
         
          
           p
           12
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              12
             
             
              +
               
              
               χ
               11
              
             
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            1
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              
               1
               ⁢
               N
              
             
             
              +
               
              
               χ
               11
              
             
            
            )
           
          
         
        
       
       
        
         
          
           p
           21
          
          ⁢
          
           e
           
            j
            ⁢
            
             χ
             21
            
           
          
         
        
        
         
          
           p
           22
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              22
             
             
              +
               
              
               χ
               21
              
             
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            2
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              
               2
               ⁢
               N
              
             
             
              +
               
              
               χ
               21
              
             
            
            )
           
          
         
        
       
       
        
         ⋮
        
        
         ⋮
        
        
         ⋱
        
        
         ⋮
        
       
       
        
         
          
           p
           
            N
            ⁢
            1
           
          
          ⁢
          
           e
           
            j
            ⁢
            
             χ
             
              N
              ⁢
              1
             
            
           
          
         
        
        
         
          
           p
           
            N
            ⁢
            2
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              
               N
               ⁢
               2
              
             
             
              +
               
              
               χ
               
                N
                ⁢
                1
               
              
             
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           NN
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             
              ∂
              
               N
               ⁢
               N
              
             
             
              +
               
              
               χ
               
                N
                ⁢
                1
               
              
             
            
            )
           
          
         
        
       
      
      ]
     
    
   
  
  
   
    
     =
     
     
      
       [
       
        
         
          
           e
           
            j
            ⁢
            
             χ
             11
            
           
          
         
         
          0
         
         
          …
         
         
          0
         
        
        
         
          0
         
         
          
           e
           
            j
            ⁡
            (
            
             χ
             21
            
            )
           
          
         
         
          …
         
         
          0
         
        
        
         
          ⋮
         
         
          ⋮
         
         
          ⋱
         
         
          ⋮
         
        
        
         
          0
         
         
          0
         
         
          …
         
         
          
           e
           
            j
            ⁡
            (
            
             χ
             
              N
              ⁢
              1
             
            
            )
           
          
         
        
       
       ]
      
      [
      
       
        
         
          p
          11
         
        
        
         
          
           p
           12
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             12
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            1
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              1
              ⁢
              N
             
            
            )
           
          
         
        
       
       
        
         
          p
          21
         
        
        
         
          
           p
           22
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             22
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            2
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              2
              ⁢
              N
             
            
            )
           
          
         
        
       
       
        
         ⋮
        
        
         ⋮
        
        
         ⋱
        
        
         ⋮
        
       
       
        
         
          p
          
           N
           ⁢
           1
          
         
        
        
         
          
           p
           
            N
            ⁢
            2
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              N
              ⁢
              2
             
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            N
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              N
              ⁢
              N
             
            
            )
           
          
         
        
       
      
      ]
     
    
   
  
  
   
    
     E
     =
     
     
      
       [
       
        
         
          
           e
           
            j
            ⁢
            
             χ
             11
            
           
          
         
         
          0
         
         
          …
         
         
          0
         
        
        
         
          0
         
         
          
           e
           
            j
            ⁡
            (
            
             χ
             21
            
            )
           
          
         
         
          …
         
         
          0
         
        
        
         
          ⋮
         
         
          ⋮
         
         
          ⋱
         
         
          ⋮
         
        
        
         
          0
         
         
          0
         
         
          …
         
         
          
           e
           
            j
            ⁡
            (
            
             χ
             
              N
              ⁢
              1
             
            
            )
           
          
         
        
       
       ]
      
      ⁢
         
      and
     
    
   
  
  
   
    
     
      P
      B
     
     =
     
     
      [
      
       
        
         
          p
          11
         
        
        
         
          
           p
           12
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             12
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            1
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              1
              ⁢
              N
             
            
            )
           
          
         
        
       
       
        
         
          p
          21
         
        
        
         
          
           p
           22
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             22
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            2
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              2
              ⁢
              N
             
            
            )
           
          
         
        
       
       
        
         ⋮
        
        
         ⋮
        
        
         ⋱
        
        
         ⋮
        
       
       
        
         
          p
          
           N
           ⁢
           1
          
         
        
        
         
          
           p
           
            N
            ⁢
            2
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              N
              ⁢
              2
             
            
            )
           
          
         
        
        
         …
        
        
         
          
           p
           
            N
            ⁢
            N
           
          
          ⁢
          
           e
           
            j
            ⁡
            (
            
             ∂
             
              N
              ⁢
              N
             
            
            )
           
          
         
        
       
      
      ]
     
    
   
  
 

where N represents the number of test antennas and the number of receivers of the device under test, P is the propagation matrix, pxy represents a change in amplitude of a signal sent from a yth test antenna to an xth receiver, a value range for x and y is 1 to N, ej(χn1) is phase information associated with a change in phase of the signal sent from the first test antenna to an nth receiver and is unknown, ∂xy is a phase difference obtained by subtracting the change in the phase of the signal sent from the first test antenna to an xth receiver from the change in the phase of the signal sent from a yth test antenna to the xth receiver, E is a matrix of ej(χn1) obtained from the propagation matrix and is unknown, PB is a matrix of pxy and ∂xy obtained from the propagation matrix; and
obtaining the inverse matrix based on the matrix PB.