Abstract: For the purpose of estimation of the along-track baseline in the absence of an auxiliary calibrating source, a new algorithm which is performed in two stages is proposed. The first stage is carried out at Doppler beam sharpening (DBS) images to estimate channel phase relationship by eigen-decomposing of the phase correlation matrix. Thus the problem of target signal contamination can be alleviated observably. Finally, the along-track baseline is estimated based on the unwrap phase of the clutter space steering vector by using the least square algorithm. The effectiveness for along-track baseline mismatch and the robustness for target signal contamination are confirmed by performance analysis and extensive simulation.

Key words: ground moving target indication, STAP, ATI, error calibration