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4.2.1 Searching Reference
4.2.1.1 DVB C/N Threshold
The antenna searches for the satellite using the DVB tuner and a C/N threshold level.
The antenna “believes” that it points towards the target satellite whenever the DVB C/N
level is above the threshold. Hence, the threshold level value should be carefully
selected to ensure the success of the searching process.
4.2.1.2 DVB AGC Threshold
The antenna searches for the satellite using the DVB tuner and an AGC threshold level.
The DVB tuner measures a power spectrum of about 2 MHz at its tuned center
frequency and represents its strength as an AGC level (higher is stronger).
The antenna “believes” that it is pointing towards the target satellite whenever the DVB
AGC level is above the preset threshold. Hence, the threshold level value should be
carefully selected to ensure the success of the searching process.
4.2.1.3 RSSD Threshold
The antenna searches for the satellite using an RSSD threshold level.
RSSD measures a power spectrum of about 50 KHz at its tuned center frequency and
represents the strength as an RSSD level (higher is stronger). The antenna “believes”
that it points towards the target satellite whenever the RSSD level is above the threshold.
Hence, the threshold level value should be carefully selected to ensure the success of the
searching process.
4.2.1.4 DVB Carrier Lock Bit
The antenna searches for the satellite using the DVB carrier lock.
We recommend a DVB carrier lock bit as a searching reference if a DVB carrier is
available. The search speed is much faster than other searching references.
If the antenna points towards the target satellite and the DVB tuner has the correct
carrier parameters, the DVB demodulator locks on the carrier and sets the lock bit on,
which means the antenna is pointing towards the correct satellite, provided that an
Summary of Contents for Ku-BAND RX
Page 1: ...INSTALLATION AND OPERATION MANUAL FOR VSAT VS61 Ku BAND TX RX ANTENNAS...
Page 15: ...7 Figure 3 1 Best Location Figure 3 2 Antenna Blockages...
Page 46: ...38 Figure 4 1 Step 1 of Reference Searching Definition...
Page 65: ...57 Figure 6 3 Co pol Kits Optional...
Page 120: ...d Appendix C Layout of Radome and Antenna Mounting Holes Figure C 1 Plastic Radome...
Page 121: ...e Figure C 2 FRP Radome Option...
Page 122: ...f...
Page 123: ...g Maritime Satellite Antenna...