A Radar Pulse Compression Approach Based on Spline Interpolation

Pulse compression is employed in radar applications when it is necessary to jointly achieve sufficient sensitivity and good range resolution while employing low peak transmit power. Nonlinear frequency modulated waveforms are often considered to pursue these objectives. Pulse compression performances are typically measured based on the extension of the mainlobe and on the level of the sidelobes of the pulse autocorrelation function if a matched filter is used in reception. If not, the same criterion is used, applied to the output of the receive filter that is not matched to the pulsed waveform used in transmission. Several design methods have been proposed in the literature differing in the parametrization of the pulse, the optimization methods, and the requirements derived from the applications. In this paper, we propose a novel method of pulse compression based on the expression of the instantaneous frequency by means of cubic spline interpolation and on the optimization of an objective function related to the sidelobes energy. Several waveform design examples are shown, demonstrating how the proposed method allows extremely low sidelobes to be achieved, in comparison also to existing algorithms.