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AM Noise Measurement Fundamentals
11
Agilent E5505A User’s Guide
285
Amplitude Noise Measurement
The level of amplitude modulation sidebands is also constant with increasing
modulation frequency. The AM detector gain can thus be measured at a single
offset frequency and the same constant will apply at all offset frequencies.
Replacing the phase detector with an AM detector, the AM noise measurement
can be calibrated in the same way as PM noise measurement, except the phase
modulation must be replaced with amplitude modulation.
The AM noise measurement is a characterization of a source. The residual AM
noise of a DUT can only be made by using a source with lower AM noise, then
subtracting that AM noise from the measured output noise of the DUT. The
noise floor of this technique is the noise floor of the source.
AM noise measurement block diagrams
Figure 217
AM noise system with N5500A opt 001
Figure 218
AM noise system with external detector
DUT
E5505a_noise_sys_block_n5505a_opt001
01 Mar 04 rev 1
Signal
input
Test set
DUT
E5505a_noise_sys_block
01 Mar 04 rev 1
AM detector
Noise
input
Test set
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 ...