Simrad ARGUS FMCW 3G, Руководство пользователя

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Tracking | Argus Radar Operator Manual
It is possible to select own ship (always identified as target NR. 1), by means of the AIS list (“AIS
list” on page 110). In the targets data window, the fields related to speed, bearing, CPA and
TCPA are obviously empty. But own ship’s data visualisation is useful in order to see if own AIS
is operating correctly.
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Note: Own ship’s heading data comes from the gyro and not from the AIS. The reason is to
avoid errors when the speed is very low.
Operating with low range scale (lower than 2 NM) and with ships bigger than 24 pixels, the
visualisation on the PPI is no longer a triangle, but the ship’s profile, according to the static
data received from AIS. Both the AIS sensor position and the heading and speed vector start-
ing position will be visualised.
The AIS position is often different from the antenna radar position and from the conning
position, therefore it is important to establish the “Common Reference Point”. In our system,
the PPI centre is the position of the radar antenna, but own ship’s vector starts from the con-
ning. Range, bearing and CPA/TCPA of radar target and AIS target are always referred to the
radar antenna position. During the setup phase, the position of the AIS sensor and the radar
antenna. The system can be set to refer the GPS data to the radar antenna position, and vice
versa (and forward these data to the other ships). If AIS is installed, own ship dimensions are
picked up from the AIS messages.
AIS ship outline viewing conditions
To view the outline of the AIS target, the following conditions must be met:
1. The ship’s profile must be present, viewed on the PPI.
2. The target heading is necessary.
3. Information such as the beam and length of the ship is needed.
4.
AIS conning position coordinates are required.
5. It is not possible to draw an outline for targets such as ATON or SAR.
6. The width of the target (represented) must be no less than 4 mm.
7. Speed information (SOG and COG) must be available.
8.
The AIS target must not be lost.
9. The AIS target must be active.
Target overload
A target overload is signalled in tracking section of the system data area in two small labels.
For both AIS and radar targets the label background turns yellow when 95% of the maximum
number of AIS/radar targets is reached (285 for AIS, 95 for radar targets on CAT1/2. Limits are
different in CAT3, see table in page 15).
For radar targets it is still possible to acquire targets until a target overflow is presented with
a red background and a warning, which signals that no other acquisitions are possible until a
target is lost or has been cancelled.
For AIS targets, the label turns red when the sum of sleeping and activated AIS targets reach
the maximum allowed.
During AIS overflow, a mechanism of priority starts to work to select which target should be
presented according to different strategies that are user selectable (see “AIS limit priority” on
page 111).
Radar target trails
Trails are artificial afterglow of the radar image on the PPI, created by maintaining the echo
intensity once it has been seen, and then gradually reducing the intensity, scan by scan.Target
trails may be shown in blue tone, instead of the normal video color (usually yellow). Gradual
shading paints the trails, getting thinner over time just like the afterglow on an old CRT type
radar. Pressing the RT/TT shortcut permits to change from RT Relative Trails to TT True Trails or
vice versa. Pressing the Trails button, a list will open with the following selection: