Specifications

11
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安捷倫科技高頻元件量測研討會
Feb.23, 2006
Assumptions for TRL (and Unknown Thru)
8-term error model assume match at each test port remains
constant, independent of whether it is a source or receiver
With real hardware, assumption is poor due to port switch
Generalized S-parameters for a two-port device:
1
11
21
22
12
22
22
11
21
22
12
11
11
2221
1211
1
1
−










•










=






a
a
a
a
a
b
a
b
a
b
a
b
SS
SS
Ideal S-parameters Switch correction
Note: a
11
= a
1
f
; a
12
= a
1
r
a
21
= a
2
f
; a
22
= a
2
r
b
1
a
1
a
2
b
2
Page 22
安捷倫科技高頻元件量測研討會
Feb.23, 2006
Two-Port Four-Receiver VNAs (like PNA)
Dual reflectometers replaced by splitters and 3-port couplers
Incident wave detection is still after the port switch
Switch corrections a
12
/a
22
and a
21
/a
11
can be directly measured
R1
R2
RF Source
LO
Test port 2
B
A
Test port 1