Estimation of Oscillator’s Phase Offset, Frequency Offset and Rate of Change for Bistatic Interferometric SAR

Inhalt:
This paper presents an approach to estimate relative phase errors for bistatic interferometric SAR systems. Phase errors that are caused by the offset of local oscillators and the relative motion of the platforms are crucial and needed to be compensated for when coherent signal processing is concerned. To directly estimate the phase errors, we introduce an additional communications channel between two platforms and the synchronization signal. An Extended Kalman Filter (EKF) is used to process the discrete received synchronization signal to estimate the relative phase errors. The simulation results show that the estimation variance achieves the Cramer- Rao Lower Bound (CRLB) at high signal-to-noise ratio (SNR).