Dvb-T Signals - Promax PRODIG-3 Manual Del Usaurio

USER'S MANUAL. PRODIG-3
3) Enter the parameters relative to the digital signal which appear in the
measurement CONFIGURATION menu, as described previously.
4) Select the option to exit from measurements CONFIGURATION menu.
5.14.5.1

DVB-T signals

Once determined the parameters of COFDM signal, it will be possible to measure
BER.
Two types of measurements appear:
Following is shown the BER measurement before the error corrections: BER
before the FEC: CBER.
MPEG-2
Figure 24.- Screen of CBER measurement (COFDM signals).
In a reception system of terrestrial digital signal, after the COFDM decoder two
error correction methods are applied. Obviously, each time we apply an error corrector
to the digital signal, the error rate changes, therefore if we measure the error rate at the
output of the COFDM demodulator, at the output of the Viterbi decoder, and at the
output of the Reed-Solomon decoder, we obtain nothing more than different error rates.
The PRODIG-3 provides the BER after Viterbi (VBER).
03/2008
-6 -5 -4
FREQ: 650.00 MHz
-3 kHz
CH: 43
Figure 25.- COFDM reception system.
-3 -2 -1
C/N: >21.3 dB
POWER: 55.8 dBµV
MER: 19.5 dB
» CBER: 5.0E-4
VBER: 5.3E-5
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