IPC-TM-650 EN 2022 试验方法1.pdf - 第479页

Figure 5-6 Measure ment of Inciden t Step Amp litude 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,Re…

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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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Figure 5-7 Calibration of Transfer Standard
TIME
TDR
INSTRUMENT
SPD
TRANSFER
STANDARD
AIRLINE
PRECISION
RF CABLE
MEASUREMENT ZONE
for REFERENCE LINE
i,Ref
f,Ref
MEASUREMENT ZONE
for AIR LINE
f,std
i,std
Figure 5-8 TDR Measurement of Transmission Line Under Test
TDR
INSTRUMENT
SPD
TRANSFER
STANDARD
TIME
MEASUREMENT ZONE
for TRANSMISSION
LINE UNDER TEST
TRANSMISSION LINE UNDER TEST
PRECISION
RF CABLE
MEASUREMENT ZONE
for TRANSFER STANDARD
i,Ref
f,Ref
i,TL
f,TL
IPC-TM-650
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