Cancellation of Doppler Distortion in Pulse Compression for Targets Moving in an Arbitrary Direction

Jie Yang, Tapan K. Sarkar
2007 Radar Conference, IEEE  
resolution of a radar system does not necessarily depend on the Abstract It can be shown that the hyperbolic frequency duration ofthe transmitted pulse, but depends on the bandwidth modulated waveform is Doppler-invariant only when the Doppler of the pulse [1]. In the modulation stage, the transmitted signal factor is a constant number, i.e., the target has a constant velocity is modulated by a linear chirp to increase the bandwidth of the and along the direction from the radar to the target.
more » ... ar to the target. If the target pulse.Ith opesostgth eevdsga1Spsd moves in an arbitrary direction, the degradation of the pulse t I thedompressionsae mtch ed sn is pansed compression caused by the mismatch between the reflected signal through a matched filter which is matched to the transmitted and the matched filter may still exist. In this paper we waveform, which results in an extremely narrow pulse with a demonstrate that the Doppler effect caused by the moving target large peak value, thus the transmitted pulse is compressed in in an arbitrary direction can be approximated by a target with an the time domain [2] . However the received signal is distorted initial velocity and a constant acceleration along the direction and does not match with the matched filter due to the Doppler from the radar to the target, which results in a frequency shift in the~~~~~relce.aeom hrfr abn fmthdfleswt effect if the relative velocity between the radar and the target is the reflected waveform. Therefore a bank of matched filters with pre-selected values of frequency shifts can be utilized to relatively large compared with the velocity of signal compensate for the Doppler effect. Numerical examples with propagation. The performance degradation of a linear target moving in an arbitrary direction are presented to illustrate frequency modulated (LFM) pulse compression system caused this effect, which have been successfully compensated by shifting by this mismatch has been studied by many researchers in [3] [4] [5] . the frequency response of the matched filter. Kelly and Wishner [6] parameterize the returned signal and modify the matched filters and ambiguity functions to compensate for the Doppler effect. Rihaczer [7] extended their Arbindexry s-Doppler-Invariant, Pus Copein, work by applying a complex notation to take into account the Arbitrary Direction Doppler-caused amplitude changes in the returned signal. Kramer [8] uses different reference signals (lines with different
doi:10.1109/radar.2007.374231 fatcat:skkftp4i6vaozosdfuzboxvioy