Settings
98-175666-A
Chapter 4: Setup of the antenna
4-16
To set up a blocking zone, do as follows:
1. Select
Settings > Blocking zones
.
2. Select
Active
to enable the blocking zone and display it in the blocking map. Gray
shading shows a blocking zone, red shading shows a
No TX
zone.
3. Enter start and stop azimuth value in degrees for the blocking zone. Values allowed: 0 to
360 degrees. Enter clockwise.
4. Enter the start and stop elevation angle for the blocking zone. If you enter nothing,
there will be no blocking zone. Values allowed: -30 to 90 degrees.
5. Select
No TX
for zones if you don’t want the system to transmit when the antenna
points within this zone (e.g. no radiation exposure on sun deck or bridge).
If
No TX
is not selected, the system also transmits when pointing through areas with
blocking objects. The VSAT modem will shut off for TX if no signal is received.
6. Click
Apply
to save the blocking zones.
Blocking map for optimization of blocking zones
The blocking map is intended as a tool to optimise the blocking zones in order to reduce the
antenna’s downtime. It shows the active blocking zones and an automatic evaluation of the
antenna reception. Over time the antenna can determine where the signal is blocked by
structures on the ship. The blocking map helps you to set more accurate blocking zones.
To enable a blocking zone and display it on the blocking map you must select
Active
. The
re-defined zones will show immediately on the map. The blocking map is updated every 12
hours, showing whether the antenna has been in a blocking zone or has received a signal.
After a voyage of days, weeks, months the blocking map will display where the blocking
zones are. The time it takes to draw a meaningful map depends on the ship’s size and
motions throughout the voyage. A small ship following a school of fish will have a
populated map faster than a larger tanker sailing across the Atlantic ocean. The following
figure shows an example.
You can clear the map at any time.
Important
You must enter 2 different elevation angles to have an active blocking
zone.
Note
If a blocking zone is defined with
No TX
not checked, the modem is not
informed about the blocking zone.
Modems may react differently when informed about a blocking zone, this
has influence on recapturing the link. The worst case is that the modem will
search the entire list of available satellites and frequencies when unaware of
the blocking zone, resulting in prolonged down times until the link is
recaptured. For optimum performance it is recommended to check
No TX
.
