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Text File  |  1983-10-04  |  2KB  |  57 lines
  1.     it would be helpful if we defined it in terms of S-parameters.
  2.     This will save us room in the network topology for the embed-
  3.     ding network, plus save us execution time.  First, we can
  4.     find the following from the manufacturer's data:
  5.     
  6.          C   = 10,000 to 20,000 umhos         g   = 150 umhos
  7.           fs                                   os
  8.  
  9.          C   = 1.8 pF                         C   = 4.3 pF
  10.           gd                                   gs
  11.  
  12.          Using this, we can derive the following model for the
  13.     device:
  14.  
  15.                                               
  16.                                                   C1 = 4.3 pF
  17.  
  18.                                                   C2 = 1.8 pF
  19.  
  20.                                                   GM1 = .015 mho
  21.  
  22.                                                   R1 = 6700 ohms
  23.  
  24.  
  25.          One form of topology for this circuit would be: 
  26.  
  27.                        ELEMENT         PARAMETER
  28.                       TYPE  NUM   #1      #2      #3
  29.                     1  CPS  1    1.8
  30.                     2  VCS  2    0.015   0
  31.                     3  CPP  3    4.3
  32.                     4  PAR  4    1       2
  33.                     5  REP  5    6700
  34.                     6  CAX  6    3       5
  35.                     1  END  6
  36.  
  37.          We shall now analyze our model from .01GHz to .1 GHz in
  38.     .01 GHz steps. 
  39.  
  40.                       FREQ        S11            S22       
  41.                      in GHz   MAG    ANGLE   MAG    ANGLE
  42.                      0.01    1      -2.68   0.985  -1.13
  43.                      0.02    1      -5.31   0.984  -2.27
  44.                      0.03    0.999  -8.02   0.983  -3.39
  45.                      0.04    0.998  -10.68  0.982  -4.52
  46.                      0.05    0.997  -13.33  0.98   -5.36
  47.                      0.06    0.996  -15.96  0.977  -6.74
  48.                      0.07    0.995  -18.57  0.975  -7.84
  49.                      0.08    0.993  -21.17  0.971  -8.91
  50.                      0.09    0.991  -23.75  0.968  -10.01
  51.                      0.1     0.99   -26.28  0.964  -11.07
  52.  
  53.  
  54.  
  55.  
  56.                                     - 20 -
  57.