Two-dimensional signal processing techniques for airborne laser bathymetry

The application of two-dimensional (2D) signal processing to data collected in airborne laser bathymetry is investigated. Specifically, a type of 2D filter for the suppression of impulsive noise in irregularly-spaced data based on order-statistics filtering is developed. An algorithm which incorporates this type of filter along with a sophisticated 2D interpolation technique is constructed to automate the filtering process. An adaptive 2D filtering technique that can be applied to raw bathymetric profiles to remove wideband noise is then discussed. The results obtained show that each type of filtering enhances the accuracy of bathymetric measurement quite significantly.