14. Ais Target Functions; Introduction - Furuno FMD-3200 Operator's Manual

14. AIS TARGET FUNCTIONS

14.1

Introduction

An AIS transponder can be connected to the ECDIS to display AIS targets received
from an AIS transponder. The ECDIS can store up to 2,000 AIS targets in its storage
buffer. When this buffer becomes full of AIS targets, Alert 190 "AIS Target Capacity
100%" is generated to alert you that the storage buffer is full. The storage buffer con-
tains automatic dead reckoning for all AIS targets, which is based on reported Speed
Over Ground (SOG), Course Over Ground (COG), Rate Of Turn (ROT) and heading.
This ECDIS can display a maximum of 1,000 AIS targets. The Alert 190 "AIS Target
Display 100%" is generated when 1,000 AIS targets, which includes both activated
and sleeping targets, are displayed.
This ECDIS can activate 500 AIS targets. The Alert 190 "AIS Target Activate 100%"
appears when 500 AIS targets are activated.
The frequency for update of AIS transponder-sent data depends on speed and course
of tracked AIS target. The table below shows the IMO standardized reporting rates for
the AIS transponder.
Class A: Navigation status is "anchor" or "not under command" or "moored"
or "aground", and SOG 0 - 3 kn
Class A: Navigation status is "anchor" or "not under command" or "moored"
or "aground", and SOG above 3 kn
Class A: SOG 0 - 14 kn
Class A: SOG 14 - 23 kn
Class A: SOG above 23 kn
Class B: "CS" SOG 0 - 2 kn
Class B: "CS" SOG above 2 kn
Class B: "SOTDMA" SOG 0 kn 0 - 2 kn
Class B: "SOTDMA" SOG 2 - 14 kn
Class B: "SOTDMA" SOG 14 - 23 kn
Class B: "SOTDMA" SOG above 23 kn
Class A and Class B: no SOG available
AIS aircraft
AIS aid to navigation
AIS base station
SART
An AIS transponder "sees" all ships fitted with a Class A or Class B AIS transponder.
Additionally the AIS transponder receives messages other than messages from ships:
• AIS Base station
• AIS on airborne SAR craft
• AIS on ATON (AIS aid to navigation)
Type of Ship
IMO
nominal reporting
interval
3 min
10 s
10 s
6 s
2 s
3 min
30 s
3 min
30 s
15 s
5 s
N/A
10 s
3 min
10 s
N/A
14-1