Micro Doppler Phenomena: Lab demonstration and Feature Extraction

This paper presents the simulation and Lab demonstration of micro Doppler feature extraction for targets having a bulk motion along with secondary rotation. A specific case of helicopter rotor blades is considered for simulation. Three methods for feature extraction namely Spectrogram, Cepstrum and Singular Value Decomposition have been discussed along with their pros and cons. Since no original target data was available, experimental data has been generated in Lab using 5.4 GHz Software Defined Radar in CW and FMCW configuration and a pedestal fan as a target. The micro Doppler features such as length of blade and rotation rate have been computed from simulated and experimental data and the deviation of results are within $\sim 6 \%$ of their true value. This establishes validity of techniques and its applicability to targets with secondary rotation motion.