Within the context of studies related to video streams, taking into account
the wireless networks, this work presents two models where one makes the prediction
of the propagation loss in the number of walls, distance and power in dB and
another to measure value loss of video quality in relation to the number of walls,
distance and power received in dB. measurement campaigns were conducted in a real
scenario of classroom blocks the UFPA Institute of Technology (ITEC) and UFPA
Telecommunication Laboratory (LCT) for the construction of the database. The
planning of these measurement campaigns took into consideration some strategies:
perform the tests using the variable distance regardless of the number of walls in the
direct path between the server and the client, fixed distance between the client and
the server and adding walls in your for path loss by obstacles and the other consists of
building radial within the environment. For modeling data averages of data collected
was used to obtain a better behavior database and thus get a better fit. It was also
applied to wastes technique in conjunction with Linear Minimum Square technique
to find the values of the constants in the equations. The propagation loss model
showed satisfactory results in comparison with ITU and Keenan-Motley models for
RMS metrics, absolute error and standard deviation related to the measured data.
The models used for comparison purposes have RMS value above 6.5 dB above
with absolute error of 6.2 dB and the standard deviation of 3 dB band, while the
proposed model has obtained an RMS of 2.99 dB, with absolute error of 2.03 dB
and a standard deviation of 3 dB. The model for loss of PSNR presented admissible
results mainly in the absolute error of 2.61 dB with RMS value of 3.75 dB and a
standard deviation of 3.9 dB.
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