Specifications

IntroductionGPS and Assisted GPS
12Operating Manual 1171.5248.12 ─ 15
2.4.1 Real-time generation
With the option GPS (R&S SMx/AMU-K44), up to four satellites per baseband can be
simulated in real-time.
In case of a two-path instrument equipped with two options GPS (R&S-K44), up to 8 real
satellites can be simulated and controlled within one dialog.
2.4.2 Multi-satellite GPS signal
The R&S Signal Generators calculates a multi-satellite GPS signal in two different modes,
the generic mode and the localization mode.
In "Generic mode", static satellites with constant Doppler shifts are provided for simple
receiver test.
The generic workflow is described in chapter 2.8.1, "Generating GPS Signal for Simple
Receiver Tests (Generic Mode)", on page 19.
The signal of dynamic real-life satellites is generated in Localization mode.
To fulfill the simulation requirements of the different application fields, the following local-
ization simulation modes are provided:
●
the "Auto SV Selection" mode
●
the "Auto SV Selection and Update" mode
●
the "Full Configuration" mode (requires option Assisted GPS R&S-K65).
Although, both the localization modes "Auto SV Selection" and "Auto SV Selection and
Update" are provided for the generation of a realistic GPS signal without limitation in the
in the validity of the navigation data, there are some differences between them. The "Auto
SV Selection and Update" mode is provided for the generation of a valid GPS signal over
long period of time and supports satellite's handover. The "Auto SV Selection" mode is
used whenever a static satellite constellation is to be tested.
Together with the "Full Configuration" mode, "Auto SV Selection" mode is also required
for the generation of customer build A-GPS test scenarios.
2.4.3 Generation of realistic GPS scenarios
The signal generation localization modes "Auto SV Selection" and "Auto SV Selection
and Update" are provided for the generation of a realistic GPS signal. In each of these
modes, the connected GPS-receiver can be forced to obtain a valid 3D fix at a predefined
or user-defined static geographical location.
Simulation of moving receiver is also possible, but this requires an instrument equipped
with the option Assisted GPS R&S-K65 (see chapter 2.6, "Moving Scenar-
ios", on page 16).
An R&S Signal Generator equipped with option GPS (R&S-K44) and working in one of
the localization modes "Auto SV Selection" or "Auto SV Selection and Update" does the
whole configuration of visible satellites and the generation of the ephemeris based on the
Functional Overview Option GPS (R&S-K44)