Patent ID: 11949424
Assignee: SHENZHEN ZHONCENT TECHNOLOGIES CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A method for frequency calibration for voltage-controlled oscillators, applied to a device for a frequency calibration for voltage-controlled oscillators, the method comprising:
dividing, by a frequency divider of the device, a signal generated by a voltage-controlled oscillator of the device that is connected with the frequency divider into N times to get a frequency division signal, where N is a positive integer;
measuring, by a time-digital converter of the device that is connected with the frequency divider, a time difference of at least two continuous or discontinuous frequency division signals and obtaining an actual time period of frequency division signal; and
generating, by a logic controller of the device that is connected with the time-digital converter, a control voltage according to the difference between the actual time period of the frequency division signal and a calibration period of the frequency division signal, and adjusting a frequency of the VCO according to the control voltage,
wherein a relationship between the control voltage and the actual time period of the frequency division signal is as follows:

Δy(k+1)=φ(k)Δu(k)

wherein u(k) is the control voltage, y(k+1) is a period of the generated frequency division signal at a k+1-th time instant, φ(k) is a time-varying parameter at a k-th time, and
wherein the logic controller is also used to estimate φ(k), get {circumflex over (φ)}(k) as follows:, φ
    ^
   
   (
   k
   )
  
  =
  
   
    
     φ
     ^
    
    (
    
     k
     -
     1
    
    )
   
   +
   
    
     ηΔ
     ⁢
     
      u
      ⁡
      (
      
       k
       -
       1
      
      )
     
     ⁢
     
      (
      
       
        Δ
        ⁢
        y
       
       -
       
        
         
          φ
          ^
         
         (
         k
         )
        
        ⁢
        Δ
        ⁢
        
         u
         ⁡
         (
         
          k
          -
          1
         
         )
        
       
      
      )
     
    
    
     μ
     +
     
      
       
        ❘
        "\[LeftBracketingBar]"
       
       
        Δ
        ⁢
        
         u
         ⁡
         (
         
          K
          -
          1
         
         )
        
       
       
        ❘
        "\[RightBracketingBar]"
       
      
      2
     
    
   
  
 

wherein {circumflex over (φ)}(k) is an estimate of φ(k), k is a frequency division time, u(k−1) is the control voltage generated according to the actual time period of measuring k−1 frequency division signal, and y(k) is the period of the frequency division signal generated immediately for the k-th time.