Promax TV EXPLORER HD+ Manual De Instrucciones página 187

USER'S MANUAL. TV EXPLORER HD+
Figure 40.- DVB-S (QPSK) signals VBER measurement screen.
In a digital reception system for satellite signals (DVB-S2), after the QPSK
decoder other two different correction methods are applied (see following Figure). In this
case, as the previous one, each time we apply an error corrector to a digital signal, the
error rate changes, therefore if we measure in a digital satellite television system, for
example, the error rate at the output of the QPSK/8PSK demodulator, at the output of
the Low Density Parity Check (LDPC) decoder, and at the output of the BCH decoder,
we obtain nothing more than different error rates. This is the reason because the BER
measurement is provided after LDPC (LBER). It also shows the amount of packet errors
(PER), that is, the amount of packets receiving during the measurement time, which are
not correctable by the demodulator (WP).
Figure 41.- Digital reception system via satellite. (DVB-S2).
Figure 42.- DVB-S2 (QPSK/8PSK) signals LBER measurement screen.
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