Sea Tel 9797B-70 C-Band TX/RX, Инструкция по установке и эксплуатации

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9797B-70 C-Band TXRX Setup
5-9
EXAMPLE 4 - Overlaid Blockage Zones: A ship has a Sea Tel antenna mounted on the center line of the
ship. A mast mounted on top of a deckhouse (like
the picture below) is forward and an engine
exhaust stack, also on a deckhouse, is aft. These
two blockage areas have wide azimuth blockage at
lower elevations and then a narrower azimuth area
of blockage extends up to a higher value of
elevation.
ZONE 1 begins (AZ LIMIT 1) at 334
degrees Relative and ends (AZ LIMIT 2) at
026 degrees Relative. Multiply these
Relative positions by 10. Enter AZ LIMIT
1 value of 3340 and AZ LIMIT 2 value of
0260. In this case the mast height only
causes blockage up to an elevation of 40
degrees, so we set EL LIMIT 12 to 0400.
If the antenna is between these two AZ
Limit points but the elevation is greater
than 40 degrees, the antenna will no
longer be blocked.
ZONE 2 begins (AZ LIMIT 3) at 352
degrees Relative and ends (AZ LIMIT 4) at
008 degrees Relative. Multiply these
Relative positions by 10. Enter AZ LIMIT
3 value of 3520 and AZ LIMIT 4 value of
0080. In this case the mast height only
causes blockage up to an elevation of 70
degrees, so we set EL LIMIT 34 to 0700.
If the antenna is between these two AZ
Limit points but the elevation is greater than 70 degrees, the antenna will no longer be blocked.
ZONE 3 begins (AZ LIMIT 5) at 155
degrees Relative and ends (AZ LIMIT 6) at
205 degrees Relative. Multiply these
Relative positions by 10. Enter AZ LIMIT
5 value of 1550 and AZ LIMIT 6 value of
2050. In this case the mast height only
causes blockage up to an elevation of 30
degrees, so we set EL LIMIT 56 to 0300.
If the antenna is between these two AZ
Limit points but the elevation is greater
than 30 degrees, the antenna will no
longer be blocked.
ZONE 4 begins (AZ LIMIT 7) at 173
degrees Relative and ends (AZ LIMIT 8) at
187 degrees Relative. Multiply these Relative positions by 10. Enter AZ LIMIT 7 value of 1730 and
AZ LIMIT 8 value of 1870. In this case the mast height only causes blockage up to an elevation of
55 degrees, so we set EL LIMIT 78 to 0550. If the antenna is between these two AZ Limit points but
the elevation is greater than 55 degrees, the antenna will no longer be blocked. If your ACU
software includes 5 volt polarization you will not see these AZ & EL LIMIT parameters.