Localization and 3D Reconstruction of Urban Scenes Using GPS | PDF

What if you could create 3D maps of cities simply by carrying your phone? Buildings block the GPS signal, so as you move, the phone gets an idea of the shape of the surrounding buildings.

Kihwan Kim, Jay Summet, Thad Starner, Daniel Ashbrook, Mrunal Kapade and Irfan Essa. In Proceedings of IEEE Symposium on Wearable Computing (ISWC) 2008.
Abstract: Using off-the-shelf Global Positioning System (GPS) units, we reconstruct buildings in 3D by exploiting the reduction in signal to noise ratio (SNR) that occurs when the buildings obstruct the line-of-sight between the moving units and the orbiting satellites. We measure the size and height of skyscrapers as well as automatically constructing a density map representing the location of multiple buildings in an urban landscape. If deployed on a large scale, via a cellular service provider’s GPS-enabled mobile phones or GPS-tracked delivery vehicles, the system could provide an inexpensive means of continuously creating and updating 3D maps of urban environments.