Parametric detection of the helicopter hub echo

Abstract

The paper presents a parametric detector optimized for the detection of the helicopter main rotor hub radar echo. The hub echo is modeled in the frequency domain as band noise spread around the Doppler frequency of the helicopter fuselage backscatter. A detection algorithm is proposed to distinguish, with relatively short available data batch, between the fuselage spectral line and those being hub spectrum components, referred to as the hub spectrum "shelf". FFT based procedures usually show too low frequency resolution and the hub echo may go undetected. The incorporation of a theoretical model of the rotor hub backscatter into the detection algorithm has led to a parametric detector of much higher frequency resolution, which can be effective in detection and classification of helicopter echoes in radar systems with inherent short time-on-target. The results of Monte-Carlo simulation of both FFT-based and parametric detector are also presented.