Spectracom GSG-5 series, User Manual With Scpi Manual

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The Propagation environment is defined by the environment type (open/rural/sub- urban/
urban) and three parameters:
Open sky limit, Obstruction limit and NLOS probability.
Default values for the parameters in each environment type are given in the table below. The
Open environment type is the default, meaning that all satellites assume free-space propaga
tion.
Table 3-1:
Propagation environment type parameters
Environment Open sky limit Obstruction limit NLOS probability
Rural 20° 15° 0.1
Suburban 40° 30° 0.2
Urban 60° 40° 0.3
The Propagation environment model is taken into use by setting an event
scenario
propenv
. If stated without parameters, the default parameter values given above will be
used. In this case the format of the even line is:
TIME scenario propenv {open|rural|suburban|urban}
Note:
For more information on
Event simulation
, see "Event Data" on page 50 .
Alternatively, parameter values can be provided in the format:
TIME scenario propenv {rural|suburban|urban} OPENSKYLIMIT
OBSTRUCTIONLIMIT NLOSPROBABILITY
Example
0.0 scenario propenv suburban
300.0 scenario propenv urban
600.0 scenario propenv urban 90.0 60.0 0.75
The example event file above will create a simulation starting from sub- urban environment
(default parameters). After five minutes the simulation changes to an urban environment (default
parameters) and after ten minutes to a highly obstructed urban environment where open sky
satellites do not exist (open sky limit at 90 degrees), and satellites below 60 degrees elevation
are likely to be NLOS (NLOS probability 0.75).
The Propagation environment model can be defined in the scenario configuration by using the
Scenario editor in
StudioView .
The Propagation environment model can also be set by using the corresponding SCPI com
mands (see "SOURce:SCENario:PROPenv" on page 253).
When using the Propagation environment model, note that:
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User Manual GSG-5/6 Series Rev. 26
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