Spectracom GSG-5 series, Руководство пользователя с руководством по SCPI

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The resolution is: 0.1 dBm .
Default setting: -125.0 dBm .
Note: The External Attenuation setting decreases the set Transmit Power level.
Note: When the power settings of individual channels are changed during
scenario execution (via the > Events menu, or protocol) the power range
will be further limited so that the maximum difference between the strongest
and the weakest signal is never more than 72 dB.
To access the Transmit Power view, navigate to Options > Transmit Power . This view also
allows you to adjust the external attenuation (see "Adjusting External Attenuation" on page 84),
and noise (see "Adjusting Noise Generation" on page 85).
Figure 3-24:
Configuring transmit power
Antenna cable length
The recommended Transmit power setting , assuming relatively short cables and that no
external attenuators are used, is -125.0 dBm . If long cables are used, it is recommended that
these are simulated by adjusting the external attenuation (see also "Adjusting External Atten
uation" on page 84).
The Transmit Power set in the Options menu is assigned to the signal type with the highest
power level, and all others are set relative to that.
Considerations
A common problem is that signals too strong or too weak are used. A signal too strong will typ
ically ‘jam’ the receiver, causing it to erroneously find many shadow signals. It is recommended
that you familiarize yourself with the typical signal/noise values for real satellites, and try to
obtain similar values when using this unit. When the signal strength is correctly set, the receiver
will respond directly and logically to changes in signal power.
The following table shows the offsets when referencing GPS L1 C/A as zero dB offset:
3.6 "Options" Menu
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User Manual GSG-5/6 Series Rev. 26
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