Modern "Ocean CPA" calculations typically integrate data from two primary systems:
): The vector difference between the own ship’s velocity and the target's velocity.
Provides GPS-based data including SOG (Speed Over Ground) and COG (Course Over Ground). 4. Calculation Methodology Ocean CPA method.pdf
Defining a "safe zone" around a ship rather than a single point.
More details on reliability in CPA calculations Ocean CPA method.pdf
Uses radio waves to track the relative bearing and range of nearby targets.
The CPA is traditionally calculated using vector geometry. Determine Relative Velocity ( Vrcap V sub r Ocean CPA method.pdf
Calculated by dividing the relative distance projection by the relative speed.