where M – bits per symbol.
So, using the formulas above of VPM and J. Proakis methods, it’s possible to
analyze dependencies of SER and BER from the energy parameters (SNR) of
communication channel.
4.3.
Analysis of the signal processing procedures to MSDS productivity.
One aspect of research the information abilities of MSDS flows is to determine
the spatial characteristics of service area. Since it is known that a variety of
communication systems use differently the resources allocated for messages
transmission, so the final stage of the research is to study the efficiency of the data
transmission system.
Information volume is steadily growing in today's world, which means that it must
be constantly processed and stored. But in addition to the growing problem of
information storage resources, there is the increasing demand for transferring that
information with higher data rate, and over long distances, to more consumers. That’s
why one of the aspects of the information communication channel throughput study is
a determination of the service area spatial characteristics.
Telecommunication services provisioning should be provided by needed data
rate and quality. The criterion in this case is reliability of received information, what
numerically represented as BER. Reliability in communication channels is a
characteristic of correctness the information transmission, in accordance with the
reliability criteria. It depends on the reliability criteria (dependence of the average
BER / to noise ratio:
−
=(
0
), wherein
– the signal energy,
0
– noise spectral
density), energy criteria (SNR), frequency band, propagation conditions and other
aspects. The main objective of reliability is to minimize the errors:
−
→.
You need to use higher modulations for services of high quality. The modulation
positional increase leads both to a productivity increase and reliability decrease. At the
same time, the use of error-correcting coding brings to the necessary reliability. DVB-
T2 standard uses powerful LDPC and BCH codes for error correction with a high speed
of errors correction.
Comparison of BER and SER results for various kinds of manipulations and
channel energy indicator, when using VPM and J. Proakis method shown that
there is a coincidence between the results in certain border VPM and J. Proakis
formulas of determining the errors likelihood. The difference between the calculations
still exists. The method of J. Proakis is sufficiently good and accurate only up to a
certain
ℎ
2
boundary. The larger the modulation index, the more the analytical
differences of BER by these two methods.
So we can conclude that BER values are the same for small SNR values, but with
the modulation index increase BER difference becomes more significant. We assume
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