Narrow-band radar imaging of spinning targets
According to the characteristics of narrow-band radar echoes from spinning targets, this paper applies the complex-valued back-projection method to image formation. Since it accumulates the sinusoidal phase of spinning scatterers effectively, this method can obtain high resolution imaging. The resolution and required radar pulse repetition frequency (PRF) of this method are deduced. For imaging of fast spinning targets, however, spurious peaks appear due to azimuth down sampling with a low PRF. Therefore, a signal model of azimuth down-sampled echoes is created according to the compressed sensing (CS) theory. Then an imaging method based on orthogonal matching pursuit (OMP) is proposed according to the sparsity nature of ISAR echoes. Finally, the effectiveness of the proposed methods is demonstrated using simulated data.
radar imaging spinning targets complex-valued back-projection compressed sensing orthogonal matching pursuit