Simrad NSS12, Техническое руководство

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RADAR | NSS Installation Manual
Sidelobe suppression
¼ Note: This control should only be adjusted by experienced radar users. Target loss in harbour
environments may occur if this control is not adjusted correctly.
Occasionally false target returns can occur
adjacent to strong target returns such as
large ships or container ports. This occurs
because not all of the transmitted radar
energy can be focused into a single beam
by the radar antenna, a small amount
energy is transmitted in other directions.
This energy is referred to as sidelobe
energy and occurs in all radar systems. The
returns caused by sidelobes tend to appear
as arcs:
When the radar is mounted where there are metallic objects near the radar, sidelobe energy
increases because the beam focus is degraded. The increased sidelobe returns can be elimi-
nated using the Sidelobe Suppression control in the Radar installation menu.
By default this control is set to Auto and normally should not need to be adjusted. However
if there is significant metallic clutter around the radar, sidelobe suppression may need to be
increased. The control should be adjusted as follows:
1.
Set Radar range to between 1/2 nm to 1 nm and Sidelobe Suppression to Auto.
2.
Take the vessel to a location where sidelobe returns are likely to be seen. Typically this would be near a
large ship, container port, or metal bridge
3.
Traverse the area until the strongest sidelobe returns are seen.
4.
Change Auto sidelobe suppression to OFF then select and adjust the sidelobe suppression control until
the sidelobe returns are just eliminated. You may need to monitor 5-10 radar sweeps to be sure they
have been eliminated.
5.
Traverse the area again and readjust if sidelobes returns still occur.
6.
Exit the installation menu.
Restore radar to Factory Default
This can be used to revert all user adjustments.