Doppler Compensation of Range Profiles And Moving Target Discrimination In FMCW Radar

Abstract

In our work summarized in this paper, the response equation of moving target stimulated by a high-frequency wide-band LFMCW is firstly established. Then the method of estimating the radial velocities of both clutter center and moving target is studied. Moving target can be discriminated by the time-integrated Doppler spectrum obtained from sampled data of multiple frequency sweep periods. Finally the approaches of Doppler compensation of range profile are studied. It is shown that Doppler compensation is essential for time integrating in each range resolution cell to enhance target. The compensated range profiles are more applicable for both detection and identification -3 of radar target INTRODUCTlON For ground target identification, wide-band wave form technology is used in missile-borne or airborne radar to reach high range resolmon(HRR). Under HRR circumstance, stationary or slow-moving target can be discriminated and identified by using geometrical shape and structure features of range profile.ln missile-bome or airbome application, the position and density of each scatter in target range profile are rapidly glinting due to high speed of the platform, which leads to insbbilty for both stationary and moving target Considering Doppler movement, the obtained range profiles for target identification and discrimination are not easily to be integrated for enhancement of detection performance and not adaptive to be rule-based model for target classification. In order to detect, discriminate and identify moving target in a strong moving clutter background, the processing of Doppler compensation and integration wrth range profiles is to be done. DOPPLER EFFECTS OF RANGE PROFILE Provided that the incident wave is a linear frequency modulated continuous wave(LFMCW), the parameterr of which is shown in Fig. 1, where t = nT, itn (0 5 t , 5 I",) (1 1 Let Y, denote the radial velocity of the m-th (m c [ l , M ] ) scattering center, then its time delay can be given by The demodulated signal after removing the phase item that can be neglected is M