Spectracom GSG-5 series, User Manual With Scpi Manual

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It takes 1 minute to create multipath taps during simulation. Therefore the time interval
between switching the environment model should be more than one minute.
The Event
scenario propenv
must be stated without parameters, or alternatively
with all three parameters specified.
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 chan
nels 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 scen
ario 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 tropospheric
and ionospheric models to a scenario.
To configure these models, navigate to:
Select > [Select Scenario] > Configure scenario, View 2/3 > Advanced > Atmospheric
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.
3.5 "Select" Menu
CHAPTER
3
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User Manual GSG-5/6 Series Rev. 26
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