Estimating High-Resolution Directional Clutter Maps in Forested Terrain Using Airborne Lidar Data

摘要

A priori knowledge of clutter environments is critical for understanding target detection performance from airborne sensors and optimally predicting future performance to aid in mission planning. Modern airborne lidar, also known as Airborne Laser Swath Mapping (ALSM), systems can acquire decimeter scale measurements of the 3D structure in forests and urban areas. From these measurements, high resolution clutter maps that account for variations in both 3D Cartesian coordinates and viewing direction are created. Changes in the observed signal-to-noise ratio of received GPS (Lband) signals under forest canopies are correlated with a nonlinear transformation of ALSM observations to establish approximate functional descriptions of signal attenuation. The spatial support of ALSM data, segmented along lines of sight, is made wavelength dependent so that generation of clutter maps can be extended to other signals, including FM radio and TV broadcasts, as well as optical sensors.