Extended wavenumber domain algorithm for airborne low frequency SAR in highly squinted mode

As compared to the high frequency squinted mode SAR, it is more difficult to processing the low frequency highly squinted SAR. In this paper, we present an extended wavenumber domain algorithm and study its application on low frequency highly squinted SAR imaging. The expressions of squinted SAR in wavenumber domain are deducted in detail, and the Stolt interpolation method in 2D frequency domain for squinted SAR is proposed. The performance of Range-Doppler algorithm and extended wavenumber domain algorithm for processing low frequency highly squinted SAR is compared. At last, simulation results proved that the extended wavenumber domain algorithm is more suitable for low frequency highly squinted SAR.