A system and method that determines building occupancy at a selected site by using geographically based structures to identify potential clients and to analyze aggregate carrier exposure levels at the selected site. This is achieved by using geographically based structures that are formed by geocoding...http://www.google.com.hk/patents/US5978769?utm_source=gb-gplus-share專利 US5978769 - System and method for determining and analyzing building occupancy
