11.10 DVB-S / DSS
Display of the measures of:
BERi :
error rate before Viterbi
BERo :
error rate after Viterbi
PER :
error rate after Reed Solomon (error rate paquet)
MER :
modulation error rate
LKM :
Noise margin (Link Margin)
BERx : error rate 'bits'
Ratio between the number of false bits / number of transmitted bits during the measurement time
PER : error rate 'paquets'
Ratio between the number of false packets / number of transmitted packets during the measure-
ment time
Recall: Under QPSK (DVB-S) a packet is made of 204 octets; a packet is "false" if it includes more than 8
wrong octets (correction by Reed Solomon coding). Under DSS, a packet is made of 146 octets.
7849B – 7859B – 7817B
DEMODULATEUR
TUNER
BERi
REED
DECODAGE
VITERBI
SOLOMON
BERo
PER
p.
58
MPEG