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Absolute Measurement Fundamentals
5
Agilent E5505A User’s Guide
123
An amplifier
If a source is not able to provide a sufficient output level, or if additional
isolation is needed at the output, it may be necessary to insert a low
phase-noise RF amplifier at the output of the source.
Note, however, that the noise of the inserted amplifier is also summed into the
measured noise level along with the noise of the source.
The Agilent N5507A Option K22 dual RF amplifier was designed specifically
for this purpose. This instrument is the preferred solution for tests requiring
an external amplifier.
Use the following equation to estimate what the measurement noise floor is as
a result of the added noise of an inserted amplifier:
shows an
example.
L(f) out = –174 dB + Amplifier Noise Figure – Power into Amplifier – 3dB
Figure 81
Measurement noise floor as a result of an added attenuator
E5505a_noise_floor_atten
26 Feb 04 rev 1
Noise figure = 7.5 dB
Amplifier
PIN = +7 dBm
L
(
f
) =
-
174 dBm + 7.5dB
-
(+7 dBm)
-
3 dB
L
(
f
) =
-
176.5 dBc/Hz
Summary of Contents for E1420B
Page 24: ...24 Agilent E5505A User s Guide ...
Page 46: ...46 Agilent E5505A User s Guide 2 Introduction and Measurement ...
Page 128: ...128 Agilent E5505A User s Guide 5 Absolute Measurement Fundamentals ...
Page 226: ...226 Agilent E5505A User s Guide 7 Residual Measurement Fundamentals ...
Page 322: ...322 Agilent E5505A User s Guide 13 Baseband Noise Measurement Examples ...
Page 340: ...340 Agilent E5505A User s Guide 14 Evaluating Your Measurement Results ...
Page 358: ...358 Agilent E5505A User s Guide 15 Advanced Software Features ...
Page 386: ...386 Agilent E5505A User s Guide 16 Reference Graphs and Tables ...
Page 392: ...392 Agilent E5505A User s Guide 17 System Specifications ...
Page 404: ...404 Agilent E5505A User s Guide 18 System Interconnections ...
Page 452: ...452 Agilent E5505A User s Guide 20 PC Digitizer Performance Verification ...
Page 466: ...466 Agilent E5505A User s Guide 21 Preventive Maintenance ...