Helicopter classification using time-frequency analysis

Helicopters are important targets in many ground based radar systems, and it is highly desirable to have the capability to classify the detected helicopters. It is shown that time-frequency analysis can be used to determine the number of helicopter blades unambiguously. The rotational frequency of the main rotor can be obtained once the number of blades is determined, and these values can be used to identify the types of the helicopter in question.