Posted on

SMA校正キット（校正をしてみたが）

scikit-rfを用いて、１ポート校正がうまく出来ているのか、あまり自信がありません。

import skrf as rf
from skrf.plotting import save_all_figs
from skrf.calibration import OnePort

my_ideals = rf.read_all('ideals/')
my_measured = rf.read_all('measured/')
dut = rf.Network('sma_8dB.s1p')

cal = rf.OnePort(
    ideals   = [my_ideals  [k] for k in ['sma_short', 'sma_open', 'sma_50ohm']],
    measured = [my_measured[k] for k in ['sma_short', 'sma_open', 'sma_50ohm']],
    )

caled_dut = cal.apply_cal(dut)

caled_dut.plot_s_smith()
#caled_dut.plot_s_db()
#caled_dut.plot_z_im()
#caled_dut.plot_z_im()

save_all_figs('./', format=['png'])

$ ls -l ./ideals/ ./measured/
./ideals/:
total 24
-rw-r--r--  1 user1  staff  869 Mar 31 20:02 sma_50ohm.s1p
-rw-r--r--  1 user1  staff  869 Mar 31 20:04 sma_open.s1p
-rw-r--r--  1 user1  staff  970 Mar 31 20:07 sma_short.s1p

./measured/:
total 32
-rw-r--r--  1 user1  staff  2686 Mar 31 20:13 sma_50ohm.s1p
-rw-r--r--  1 user1  staff  2450 Mar 31 20:13 sma_8dB.s1p
-rw-r--r--  1 user1  staff  2426 Mar 31 20:13 sma_open.s1p
-rw-r--r--  1 user1  staff  2337 Mar 31 20:13 sma_short.s1p

$ head ./ideals/sma_50ohm.s1p ./measured/sma_50ohm.s1p 
==> ./ideals/sma_50ohm.s1p <==
# MHz S RI R 50
0 0 0
0.3 0 0
0.6 0 0
0.9 0 0
1.2 0 0
1.5 0 0
1.8 0 0
2.1 0 0
2.4 0 0

==> ./measured/sma_50ohm.s1p <==
# MHz S RI R 50
0 0.00701499 0.00504031
0.3 0.00701499 0.00504031
0.6 0.00701499 0.00504031
0.9 0.00878989 0.0028871
1.2 0.00932459 0.00274434
1.5 0.00956452 0.00248623
1.8 0.01028 0.00211041
2.1 0.0100815 0.00206556
2.4 0.0127909 0.00148593

校正前より、良くなっているのでしょうか？