IPC-TM-650 EN 2022 试验方法1.pdf - 第478页
Figure 5-4 Determination of in stant in the TDR waveform correspon ding to the beginning of the r eference line. A is the amplitude of the signal reflected from the o pen end o f rf cable. SPD TDR INSTRUMENT PRECISION RF …
Figure 5-3 Determination of Measurement Zone
TIME
1,TL
2,TL
SPD
TRANSFER
STANDARD
TDR
INSTRUMENT
TRANSMISSION LINE UNDER TEST
MEASUREMENT ZONE
for TRANSMISSION LINE UNDER TEST
PRECISION
RF CABLE
IPC-TM-650
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Figure 5-4 Determination of instant in the TDR waveform corresponding to the beginning of the reference line. A is the
amplitude of the signal reflected from the open end of rf cable.
SPD
TDR
INSTRUMENT
PRECISION
RF CABLE
t
1,Ref
TIME
0.5
R.0
R,0
Figure 5-5 Determination of instant in TDR waveform corresponding to the end of the reference line (transfer standard or
air line reference).
is the amplitude of the signal reflected from the open end of the reference line.
SPD
TDR
INSTRUMENT
PRECISION
RF CABLE
t
1,Ref
TIME
0.5
R,0
R,0
REFERENCE LINE
t
2,Ref
IPC-TM-650
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Figure 5-6 Measurement of Incident Step Amplitude
TIME
TDR
INSTRUMENT
SPD
TRANSFER
STANDARD
MEASUREMENT ZONE
for TRANSMISSION LINE UNDER TEST
PRECISION
RF CABLE
i,TL
f,TL
MEASUREMENT ZONE
for REFERENCE LINE
i,Ref
f,Ref
IPC-TM-650
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