Keysight Technologies FieldFox A Series, Руководство пользователя

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588 Keysight N9927-90001 User’s Guide
Noise Figure Mode (Option 356 – CPU2 Only)
How to use Auto-Integration
How to use Auto-Integration
This section provides an example procedure for measuring a device using noise
figures’ auto integration feature. This example does not use an external preamp
and was performed over a long time duration. Auto-integration is
recommended to achieve greater accuracy and speed for all of your device
measurements. Refer to Figure 29-14 on page 592 and Figure 29-14 on
page 592 .
For the following example, these settings were used on the FieldFox with a
Keysight 346C K01 noise source that had the following characteristics:
About Auto-Integration
With auto integration, the FieldFox Noise Figure application chooses the
optimum integration time for each of the noise power measurements needed
(i.e., noise source on, noise source off, and receiver reference) to compute the
device's noise figure with the selected amount of measurement jitter in the
shortest possible time. The auto integration feature calculates the time
required to satisfy the jitter goal from the relative power levels as they are
measured. One significant advantage of auto integration is that it ensures that
the best possible instrument speed is used in achieving the necessary jitter
requirement.
If, on the other hand, it is determined that the time required to meet the jitter
goal exceeds the maximum allowed time set by the user, auto integration will
divide the maximum allowed time between the power measurements in order
to produce the smallest possible jitter in the noise figure measurement. In
For optimum speed and performance measurement results, it is
recommended that auto-integration is used in all noise figure
measurements.
Keysight 346C K01 characteristics at 50 GHz
ENR of 11. 8 dB
Noise figure 8.7 dB
Gain 9.5 dB
Total Noise = 18.2 dB above kTB.
FieldFox N9952A noise figure (as tested): 39.3 dB
For this example, the cold noise generation of the 346C
K01 is 21.1 dB below the FieldFox’s noise power (i.e.,
39.3 dB – 18.2 dB = 21.1 dB).