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ANTRF
2011-02-07, 04:47 PM
WIDEBAND CHANNEL CHARACTERIZATION:
SIMULATION AND MEASUREMENTS ANALYSIS.

The development of wireless telecommunication requires higher speed data rates. Wideband
MIMO systems are a possible answer to that need. Both wideband and MIMO characteristics
enhance multipath propagation, and require a precise knowledge of the channel to properly
exploit their capabilities. The extraction of the channel parameters can be done from the
measurements, but also from simulations.
In the frame of this thesis, the possibility to use ray tracing to derive capacity coverage prediction
is studied, based on the comparison with measurements. First the radio channel models are
discussed, from the MIMO channel model to the ray tracing methods. Then the measurements
methods and the algorithms extracting the channel parameters are presented, before focusing on a
measurement campaign to compare prediction from ray tracing and measurements-based SAGE
algorithm. Key parameters for capacity –delay spread and angular spread– were first compared,
then capacity itself is introduced and a capacity comparison is conducted. Polarization influence
on capacity is also studied, and different methods of emulating polarization on ray tracing are
studied. Last but not least, the desired capacity coverage prediction is achieved on a wide area
around the measurement streets.
The simulation results with the ray tracing software are promising. The multipath components
were predicted well enough by ray tracing to compute capacity. Then the polarization emulating
methods gave interesting results: polarization influences capacity, and the derived capacity
values were close enough to those computed from measurement to launch a capacity coverage
calculation, first step toward a cellular planning based on MIMO capacity. However, some
uncertainties are still left, due to computation time and models approximations.


B.R.

ANTRF

tt1dks
2011-02-10, 12:09 PM
WIDEBAND CHANNEL CHARACTERIZATION:
SIMULATION AND MEASUREMENTS ANALYSIS.

The development of wireless telecommunication requires higher speed data rates. Wideband
MIMO systems are a possible answer to that need. Both wideband and MIMO characteristics
enhance multipath propagation, and require a precise knowledge of the channel to properly
exploit their capabilities. The extraction of the channel parameters can be done from the
measurements, but also from simulations.
In the frame of this thesis, the possibility to use ray tracing to derive capacity coverage prediction
is studied, based on the comparison with measurements. First the radio channel models are
discussed, from the MIMO channel model to the ray tracing methods. Then the measurements
methods and the algorithms extracting the channel parameters are presented, before focusing on a
measurement campaign to compare prediction from ray tracing and measurements-based SAGE
algorithm. Key parameters for capacity –delay spread and angular spread– were first compared,
then capacity itself is introduced and a capacity comparison is conducted. Polarization influence
on capacity is also studied, and different methods of emulating polarization on ray tracing are
studied. Last but not least, the desired capacity coverage prediction is achieved on a wide area
around the measurement streets.
The simulation results with the ray tracing software are promising. The multipath components
were predicted well enough by ray tracing to compute capacity. Then the polarization emulating
methods gave interesting results: polarization influences capacity, and the derived capacity
values were close enough to those computed from measurement to launch a capacity coverage
calculation, first step toward a cellular planning based on MIMO capacity. However, some
uncertainties are still left, due to computation time and models approximations.


B.R.

ANTRF

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thanks for sharing