1. A method for detecting a terrain profile using point cloud data, the method comprising the steps of: receiving point cloud data in a three-dimensional (3D) space from an airborne platform; reformatting the point cloud data from the 3D space into a one-dimensional (1D) space to form a 1D signal; decomposing the 1D signal using a wavelet transform (WT) to form a decomposed WT signal; reconstructing the decomposed WT signal to form a low-pass filtered profile; and classifying the low-pass filtered profile as the terrain profile.