Functionality level 1 
Functionality level 2 
Function 
input information 
Output information 
1.4 Determine bearing and 
distance 
1.4.1 Record data 
• Position of observed object 
• Position of own ship 
• Necessary input information for determining 
bearing and distance of object to the own ship 
1.4.2 Evaluate data 
• Output information from 1.4.1 
• Absolute bearing (calculated on 360°) 
• Lateral bearing (bearing calculated on heading 
of own ship, “relative bearing”) 
1.4.3 Provide information 
• Output information from 1.4.2 
• Provision of absolute/relative bearings as well 
as distance 
1.5 Determine position of 
object 
1.5.1 Record data 
• Heading of own ship 
• Visual observation 
• Necessary input information for determining the 
position of the object 
1.5.2 Evaluate data 
• Output information from 1.5.1 
• Position of object (i.e. heading of object calcu 
lated on the own heading) 
1.5.3 Provide information 
• Output information from 1.5.2 
• Provision of position of object for further proc 
essing 
1.6 Determine characteris 
tic variables 
1.6.1 Record data 
• Relative course of object (cal 
culated on own ship) 
• Relative speed of object 
• Distance and bearing of object 
• Necessary input information for determining the 
characteristic variables CPA and TCPA 
1.6.2 Evaluate data 
• Output information from 1.6.1 
• Determine characteristic variables CPA and 
TCPA 
1.6.3 Provide information 
• Output information from 1.6.2 
• Provision of characteristic variables for further 
processing 
2. Receipt of absolute object 
data 
2.1.1 Record data 
• Receipt of object data from other 
sources (VTS/transponder/AIS) 
• Object information: type, identification, position, 
movement data 
2.1.2 Evaluate data 
• Output information from 2.1.1 
• Identified object 
2.1.3 Provide information 
• Output information from 2.1.2 
• Provision of object information for use by other 
functionalities