IPC-TM-650 EN 2022 试验方法1.pdf - 第476页

Figure 5-1 Determination of in stant in the TDR waveform correspon ding to the beginning of the t ransmission lin e. A is the amplitude of the signal reflecte d from the open end of the probe. SPD is the static protection…

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IPC-TM-650
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Figure 5-1 Determination of instant in the TDR waveform corresponding to the beginning of the transmission line. A is
the amplitude of the signal reflected from the open end of the probe. SPD is the static protection device (see 4.3.5).
PROBE
SPD
TDR
INSTRUMENT
PRECISION
RF CABLE
TRANSFER
STANDARD
TIME
0.5A
R,1
t
1,TL
A
R,1
Figure 5-2 Determination of instant in TDR waveform corresponding to the end of the transmission line. is the
amplitude of the signal reflected from the open end of the transmission line under test.
SPD
TRANSFER
STANDARD
TDR
INSTRUMENT
TRANSMISSION LINE UNDER TEST
0.5
R2
TIME
t
1,TL
t
2,TL
R2
PRECISION
RF CABLE
IPC-TM-650
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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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