Selecting The Measurements - Promax US TV EXPLORER 2 User Manual

USER'S MANUAL. US TV EXPLORER II
5.14

Selecting the Measurements

The types of measurements available depend on the operating band (terrestrial or
satellite) and the type of signals (analogue or digital).
Terrestrial band - Analogue channels:
Level Level measurement of the currently tuned carrier.
Video / Audio Video carrier to audio carrier ratio.
C/N Ratio between the modulated signal power and the equivalent
noise power for a same bandwidth. (according to TV standard)
FM Deviation Measure the frequency peak deviation for any modulated
analogue carrier in FM.
Terrestrial band - Digital channels (ITU-T J.83/B (QAM Annex-B) and ATSC (8-VSB)):
Channel power Channel power is measured assuming that power spectral
density is uniform throughout channel bandwidth.
MER Modulation error ratio measurement.
SER (only for ATSC) MPEG wrong packets measurement, which
have not been corrected by means of the FEC.
VBER (only for ATSC) BER (Bit error rate) measurement for the digital
signal after the error correction (BER after Viterbi).
BER (only for ITU-T J.83/B) BER (Bit error rate) measurement for the
digital signal after the error correction (BER after Viterbi).
C/N Out-channel measurement. Noise level is measured at f noise =
f tuning ± ½*Channel BW. To measure it correctly digital
channel must be tuned at its central frequency.
:
NOTE The BER/VBER measurement shown by default (when PRN-23 BER option
from Preferences menu is set to OFF) yields an estimated value calculated
using the MER measurement. In order to obtain a more accurate BER
measurement value, the PRN-23 BER option from Preferences menu must be
set to ON and a PRN-23 signal pattern must be used through the RF signal
input [30].
If the input signal is like PRN-23 or a video signal, the BER and VBER
measurement are considered as acceptable when BER/VBER ≤ 3*10E-6 and
SER-ERR/s ≤ 2 being SER value the number of wrong packets taken as
reference measurement.
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