An Overview of the Probability Density Function (PDF) Tracker
B.M. Shapo, R.E. Bethel · 2006
The PDF tracker first entered Navy passive sonar in the Passive Tracking Algorithm (PTA) Air ASW program. Since then, it has fulfilled the role of frequency line tracker (frequency versus time surface) as well as broadband (bearing vs. time) tracker in various fleet systems. These deployments have included both stand-alone implementations and also integration with other tools. Examples are TRAFS and WSQ-11 in the surface community, as well as HPT, HCF, IPT, and ICF on submarine systems