Nera NWC Voyager, User Manual

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USER GUIDE
SYSTEM DESCRIPTION
CONT
’
D
NWC Voyager
Antenna search pattern
Azimuth sweep
A 360° rotation of the antenna in azimuth at a fixed
elevation angle. The turn rate is 50° per second.
Hemispheric search
A hemispheric search is constituted by azimuth
sweeps at elevation angles 5°, 25°, 45°, 65° and 85°.
The antenna searches on the NCS Common TDM
channel frequency (NCSC), initiated by the Main
Communication Unit (MCU) of NWC Voyager.
When finding the satellite signal, it completes the
hemispheric search and moves to the position where
the strongest signal was detected.
The antenna reports back to the MCU for verification
of valid NCSC.
If no valid signal is detected, no further automatic
action occurs until the MCU initiates a new search.
A search request from the MCU may contain channel
frequency and an order to make a full 360° search at
a specific elevation , memorized from last time. The
system only searches for the last two satellites, unless
the user selects another manually. If no satellite is
found, a hemispheric searc h will be performed.
Tracking
At the end of a search, NWC Voyager performs a fine-
tuning of the antenna position around the strongest
detected signal. The fine-tuning is obtained by a
squinting function based on satellite signal quality.
5°
25°
45°
65°
85°
360° AZIMUTH SWEEP
HEMISPH
ERIC
SE
AR
CH
ELEVAT
ION
AN
GL
ES
Note! NWC Voyager remembers the last
used Ocean Region when switching the
terminal off/on.