limited communication channels, namely the frequency and energy resources. The
scientists and engineers have a task of best use these resources and keep the main
channel characteristics on the original expected level.
The information efficiency indicator describes channel resources efficiency
usage, which is the ratio of channel productivity to channel throughput. It is necessary
to operate with the optimal MCS choice to achieve a high rate of information
efficiency. Right MCS is needed to deliver the best combinations of data rate and
reliability under the given conditions in communication channel.
The DVB-T2 television broadcasting standard and its main features analyzed in
this work, and considered for borrowing them for MSDS in order to improve system
and link productivity when transmitting multi-service information. The DVB-T2
features and their differences from its predecessor DVB-T are analyzed. Then,
according to the certain specified criteria and requirements in work, MSDS proposed.
The influence of energy factors on system productivity and its throughput investigated.
The methods for calculating coverage areas in wireless networks are classified by
comparative analysis of spatial models. As a result, the Okamura-Khata model for
MSDS indicators calculation is selected.
The basic performance indicators explored for MSDS while using the DVB-T2
standard. The features and definition of productivity, throughput explained.
SER and BER calculated using several techniques, namely vector-phase method
and J. Proakis formulas; presented analytical and graphical results. In addition, built a
table with BER and SER comparison for different calculation methods.
Analyzed and described methods for improving productivity of MSDS; in
particular, the use of multi-position signals explored in combination with rational code
rates with limited frequency and energy resources.
The productivity estimation is performed in work. It’s one of parameters for
information efficiency calculation. Based on this, the graph is built for 24-stages code
rate combinations 1/2, 3/5, 2/3, 3/4, 4/5, 5/6 and for modulations QPSK, 16-QAM, 64-
QAM, 256-QAM that are used from the DVB-T2 standard, that helps to identify
necessary and redundant MCSs that can be excluded. Calculated main indicators of the
communication channel with the spatial Okamura-Khata model such as the propagation
distance, system performance and others, including all modulation and coding
gradations.
Based on the performed calculations, the redundant MCSs are identified that can
be excluded from the DVB-T2 standard if use in new communication system with
using features of DVB-T2. As a result, from the available 24 MCSs the 7 MCSs are
recommended for use (QPSK with a code rate 1/2, 16-QAM – 3/5, 3/4 and 4/5, QAM-
64 – 3/5, 3/4 and 5/6), while the final system productivity loss is only 11.5% (and
MCSs reduction is 71%). The losses percentage is tiny for whole communication
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