基于改进的相干法的InSAS三维地形生成方法

Method of DEM reconstruction of InSAS based on improved coherence

提出了一种利用时延测距进行干涉合成孔径声纳(InSAS)数字高程模型(DEM)重建的方法。重点研究了采用相干系数估计两幅合成孔径图像的时延,并利用插值和相位修正提高时延估计精度的方法。分析了时延估计过程中可能出现的时延跳变情况,并给出了解决办法。采用仿真数据和干涉合成孔径声纳样机实测数据对所提方法进行了验证,结果表明:该方法是有效的,能够获得可靠的高程结果。相比传统的干涉处理方法,该方法避免了图像配准、相位滤波、解卷等步骤,实现起来更加简便。

A time delay estimation based on method for synthetic aperture sonar interferometric height estimation was presented. The coherence function was suggested in estimating the time difference con- tained in synthetic aperture image pairs. Ways of improving time difference estimation accuracy, such as interpolation and phase correction, were especially analyzed. The phenomenon of time difference discontinuyty jump was analyzed and resolved. Simulation and lake-trial real data were carried out to verify the proposed method. The processing results show that the method is effective and can obtain accurate DEM. Besides, the proposed method simplifies the procedures of the traditional methods and is more easier to realize.