Patent ID: 8842041

Claim:
In a transportation system including at least a first container monitored by a first monitoring unit and having a first GPS transponder, and a second container monitored by a second monitoring unit and having a second GPS transponder, a method for determining the location of at least one container, the method comprising: determining the location for the first container from the first GPS transponder; determining the location of the second container from the second GPS transponder; initiating a request by the first monitoring unit for location and identifying data from the second container; reporting the location and identifying data from the first and second containers to a remote monitoring station; initiating a request by the second monitoring unit for location and identifying data from at least a third container; reporting data collected by the second container to a remote monitoring station; determining a derived location for the first and second containers based on the time and direction of the signals received from the first and second container monitoring units at the remote monitoring station; comparing the derived location of the first and second containers to the GPS determined locations of the first and second containers; creating adjusted location data for the first container based on a comparison of the derived location of the first container and the GPS determined location of the first container; and transmitting the adjusted location data to the first container.