Download QuaDRiGa - Quasi Deterministic Radio Channel Generator, User

QuaDRiGa v1.2.3-307
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RandStream . s e tG lo ba l St re am ( RandStream ( ’ mt19937ar ’ , ’ seed ’ ,5) ) ;
p = l. create_parameter_sets ;
p . p aramete r_maps (: ,: ,[2 3]) = 0;
% Fix SF and KF to 0
p . plpar = [];
% Disable path loss model
p. update_parameters ;
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Parameters
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TUTORIALS
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Now, we generate the channel coefficients. The first run uses the new drifting module, the second run
disables it. Note that drifting needs significantly more computing resources. In some scenarios it might thus
be useful to disable the feature to get quicker simulation results.
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s . d ri f t i n g _ p r e c i s i o n = 1;
RandStream . s e tG lo ba l St re am ( RandStream ( ’ mt19937ar ’ , ’ seed ’ ,2) ) ;
c = p . get_channels ;
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s . d ri f t i n g _ p r e c i s i o n = 0;
RandStream . s e tG lo ba l St re am ( RandStream ( ’ mt19937ar ’ , ’ seed ’ ,2) ) ;
d = p . get_channels ;
Channels
Channels
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Results and discussion
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The following plots represent the results of the test.
figure
distance = 20+(1: c . no_snap ) * l . track . get_length / c . no_snap ;
plot ( distance , c . delay (1 ,:) *1 e9 , ’ -b ’ )
hold on
plot ( distance , d . delay (1 ,:) *1 e9 , ’ -. b ’ )
plot ( distance , c . delay (2 ,:) *1 e9 , ’ -r ’ )
plot ( distance , d . delay (2 ,:) *1 e9 , ’ -. r ’ )
hold off
xlabel ( ’ Distance from track start point ’)
ylabel ( ’ Delay [ ns ] ’)
The first plot (Fig. 25) shows the delay of the LOS tap (blue) and the delay of the first NLOS tap (red) vs.
distance. The solid lines are from the channel with drifting, the dashed lines are from the channel without.
The LOS delay is always increasing since the Rx is moving away from the Tx. However, the increase is not
linear due to the 25 m height of the Tx. Without drifting, the delays are not updated and stay constant
during the segment. The position of the first scatterer is in close distance to the Rx (only some m away).
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Delay [ns]
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Distance from track start point
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Figure 25: Cluster delays vs. Rx position (drifting phases tutorial)
Copyright: Fraunhofer Heinrich Hertz Institute
eMail: [email protected]
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