Features
User Manual for AZ430 WAN Satellite Modem
6.2 Equalink
BER performance degradation due to transmission channel impairments is
becoming increasingly important in DVB-S2 systems operating with higher order
modulation formats (16APSK, 32APSK), in particular at the higher symbol rates.
The Equalink concept effectively optimizes satellite link performance by
counteracting these effects. Newtec DVB-S2 Modulators equipped with the
Equalink™ feature contain both linear and non-linear predistortion functions which
can be individually enabled/ disabled.
Equalink operating principle:
•
Optimum predistortion is computed off-line based on specified distortion
characteristics
•
Resulting predistortion table(s) are uploaded to the Modulator and activated
Link performance can be expressed in terms of Bit or Packet Error Rate (BER or
PER) versus Energy-per-symbol to Noise density ratio (Es/N0).
For a communication channel over a satellite link, the overall link performance can
be severely degraded by channel impairments. Examples of such impairments are:
•
Interference (Adjacent Channel Interference (ACI) and Co-Channel Interference
(CCI)
•
Inter-Modulation
(IM)
•
Adjacent Satellite Interference (ASI)...)
•
Phase
noise
•
Signal
distortions
•
...
Performance degradation due to these impairments is becoming increasingly
important in DVB-S2 systems operating with higher order modulation (16APSK,
32APSK), in particular at the higher symbol rates.
The Equalink™ concept effectively optimises satellite link performance by
counteracting these effects.
Newtec DVB-S2 Modems equipped with the Equalink™ feature contain, both linear
and non-linear predistortion functions which can be individually enabled /disabled.
Please refer to the Equalink™ User Manual for a full description of
this feature
version 1.0
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SHAPING THE FUTURE OF SATELLITE COMMUNICATIONS
