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Evaluating Your Measurement Results
14
Agilent E5505A User’s Guide
325
Comparing against expected data
If none of the problems listed appears on your graph, there still may be
problems or uncertainties that are not obvious at first glance. These
uncertainties can be evaluated by comparing your measurement results
against the following data:
•
The noise characteristics expected for your DUT.
•
The noise floor and accuracy specifications of the phase noise test system.
•
The noise characteristics of the signal source used as the reference source.
The device under test
If you are testing a product for which published specifications exist, compare
the measurement results against the noise and spur characteristics specified
for the product. If the product is operating correctly, the noise graph provided
by the phase noise system should be within the noise limits specified for the
product.
If the device is a prototype or breadboard circuit, it may be possible to
estimate its general noise characteristics using the characteristics of a similar
type of circuit operating in a similar manner.
Figure 260
Noise plot showing obvious problems
10M 40M
100
10
1
1M
100K
10K
1K
0
20
40
-20
-40
-60
-80
-100
-120
-140
-160
E5505a_noise_curve_problems
02 Mar 04 rev 1
L
(
f
) =
-
[dBc/Hz] vs.
f
[Hz]
High small
angle noise
Spurs
Breaks
High noise
level
Содержание E1420B
Страница 24: ...24 Agilent E5505A User s Guide ...
Страница 46: ...46 Agilent E5505A User s Guide 2 Introduction and Measurement ...
Страница 128: ...128 Agilent E5505A User s Guide 5 Absolute Measurement Fundamentals ...
Страница 226: ...226 Agilent E5505A User s Guide 7 Residual Measurement Fundamentals ...
Страница 322: ...322 Agilent E5505A User s Guide 13 Baseband Noise Measurement Examples ...
Страница 340: ...340 Agilent E5505A User s Guide 14 Evaluating Your Measurement Results ...
Страница 358: ...358 Agilent E5505A User s Guide 15 Advanced Software Features ...
Страница 386: ...386 Agilent E5505A User s Guide 16 Reference Graphs and Tables ...
Страница 392: ...392 Agilent E5505A User s Guide 17 System Specifications ...
Страница 404: ...404 Agilent E5505A User s Guide 18 System Interconnections ...
Страница 452: ...452 Agilent E5505A User s Guide 20 PC Digitizer Performance Verification ...
Страница 466: ...466 Agilent E5505A User s Guide 21 Preventive Maintenance ...