Orolia GSG-5 Series, User Manual With Scpi Manual, Page: 88 / 392

Valid ranges for the parameter values are:
OPENSKYLIMIT
: 0.0 to 90.0 (degrees)
OBSTRUCTIONLIMIT
: 0.0 to OPENSKYLIMIT (degrees)
NLOSPROBABILITY
: 0.0 to 1.0
It is possible that all multipath taps cannot be created because of limited number of
channels available. The Tap number defines the precedence of tap creation (direct
path first, and then second tap etc.)
The maximum number of satellites to be simulated should be set to a fixed value. If
any satellite system is set to ‘
Auto ’, no new duplicate channel can be created while
the scenario is running.
The number of multipath signals should be set to zero. When using the Propagation
environment model, the simulator automatically assigns the multipath channels.
Fading satellite signals (i.e. all satellites below the Open sky limit) are indicated by
the letter ‘
F ’ next to the satellite number in the satellite information display when
the scenario is running. Created multipath taps (taps 2 to 5) are indicated by letter
‘
D ’.
3.5.9.5 Atmospheric model
Atmospheric conditions have an effect on the propagation of GNSS signals, and as such
can be an error source. GSG allows for these effects to be simulated, by applying tro-
pospheric and ionospheric models to a scenario.
To configure these models, navigate to:
Select > [Select Scenario] > Configure scenario, View 2/3 > Advanced > Atmo-
spheric model .
Iono model
The GSG unit comes with built-in support for a model of the ionosphere. By default the
used model is a reverse model of the model described in IS- GPS- 200D, Section
20.3.3.5.2.5, called
Klobuchar .
The a0-3 and b0-3 parameters set in the default model are set by the used navigation data
files. When set to
Off , no delays caused by the ionosphere are used in the simulation.
Under normal testing conditions, the Klobuchar ionosphere model should be used.
Note: The GSG also supports simulation of ionosphere delays using files in
the IONEX format.
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3.5 "Select" Menu