KNS Ku-BAND RX, Installation And Operation Manual

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and PLL-based LNB.
NOTE : A drawback occurs when the antenna is in the tracking process and the AGC
level is below the preset threshold (logically unlocked), due to the disconnection with the
CC source. After that, the antenna restarts the searching process. This also applies to the
External Lock Bit.
4.2.1.7 External Lock Bit & C/N Threshold
The antenna searches for the satellite using the external lock bit and the C/N (AGC
value of modem) threshold level.
4.2.2 Tracking Reference
The tracking algorithm uses selected energy level variations while the antenna scanning
process is on. The tracking process is only initiated when the searching conditions have
been met.
4.2.2.1 RSSD Level
The antenna tracks the satellite by dish-scan by reading the RSSD power level of 100
KHz of the desired carrier for the target satellite. Usually, the RSSD frequency is the L-
band frequency of the target carrier, but the user can change the RSSD frequency to the
desired L-band frequency.
4.2.2.2 DVB AGC Level
The antenna tracks the satellite by dish-scan by reading the DVB AGC level changes of
the desired carrier on the target satellite. AGC level tracking may result in tracking off from
the target satellite, when there is severe interference from an adjacent satellite that has a
stronger carrier level.
4.2.2.3 DVB C/N Ratio
The antenna tracks the satellite by dish-scan by reading the DVB C/N ratio change of
the desired DVB carrier on the target satellite. The DVB tuner C/N ratio is very useful
where there is adjacent satellite interference (ASI). ASI can create a higher energy level