Patent ID: 7881733

Claim:
A method of selectively communicating with devices within defined geographical zones, comprising: defining a plurality of geographical zones, each zone being defined by predetermined attributes; associating at least one device within each geographical zone with which a portable device can communicate; providing the portable device with a ground positioning unit receiver; loading data representative of the plurality of geographical zones to the portable device; obtaining geographical coordinates of the portable device from the ground positioning unit receiver; determining the location of the portable device in relation to at least one of the plurality of geographical zones; and enabling communication with the at least one device associated to the at least one geographical zone when the portable device determines it is within the at least one geographical zone; programming the portable device to determine the occurrence of certain conditions in the at least one geographical zone that the portable device is located within the geographical zone, wherein the portable device is programmed to determine the occurrence of different conditions dependent on the at least one geographical zone; reporting the occurrence of the certain conditions; permitting the at least one device to transmit a signal to the portable device indicating the occurrence of an event; permitting a microprocessor in the portable device to execute a preconfigured operation if the microprocessor in the portable device determines that the event occurred triggers the execution of the preconfigured operation; wherein the portable device is programmed to determine if certain conditions have occurred in the geographical zone, and when a condition occurs the portable device reports the occurrence to a control center or to a second portable device; and wherein each geographical zone is depicted as a pixilated computer image created by performing the steps of: (a) allowing a user to identify a geometrical area in a computer map using two coordinate attributes; (b) dividing the identified geometrical area into a grid; wherein the grid is divided into a number of sections so as to achieve a high enough resolution to be able to correctly delineate the geographical zone; (c) allowing the user to select at least one section from within the grid in order to define the geographical zone; and (d) associating the at least one section to a pixel in a pixilated computer image such that the pixels selected b the user in the identified geometrical area are identified as being in the geographical zone.