Cell tower contrast in the visible, short-wave infrared, and long-wave infrared bands

In a GPS-denied environment, distinct structures, such as cell towers and transmission towers, are useful as an aid to vision-based navigation. Cell towers are surveyed such that their locations are well known, and the imagery of these towers can be compared to imagery databases to assist in navigation. In this research, imagery of the cell towers was taken in the visible (VIS), short-wave infrared (SWIR), and long-wave infrared (LWIR) bands with both clear sky and portions of the ground in the background. The contrast of the cell towers in the two reflective bands (VIS and SWIR) was determined against the sky and the ground in terms of equivalent reflectivity. The contrast of the cell towers was also determined in the LWIR in terms of equivalent blackbody temperature. The analysis of contrast, the results, and recommendations on band use are provided for use in three-dimensional map image comparisons.