Abstract:The feature analysis and extraction of lowaltitude targets based on LTE signal is of great significance for lowaltitude target surveillance and key site protection. One of the core techniques of LTE communication signals is multi carrier orthogonal frequency division multiplexing (OFDM), i.e. Time Division Duplex (TDD) and Frequency Division Duplex (FDD). In this paper, a radar echo model of lowaltitude targets with rotors is established based on FDDOFDM signal, the parameterized expressions of Doppler and microDoppler of target scattering points are derived, and the factors of microDoppler frequency of rotating parts are analyzed. On this basis, the micromotion parameters of the target are extracted by a method consisting of time frequency analysis and Hough transform. The feasibility and the validity of feature extraction of lowaltitude micromotion targets are verified under passive FDDOFDM bistatic radar.